| 00:00 | Okay well let's um well go Um so this is the advanced structural |
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| 00:07 | class and this afternoon we'll do an and two things on basic stress and |
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| 00:15 | . It will be a mix of talking and um some discussion points and |
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| 00:20 | exercises for you to do online and take frequent breaks throughout the course of |
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| 00:26 | whole thing and free feel free to questions at any point that that's |
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| 00:39 | Okay, so this first slide is me. Um I got my bachelor's |
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| 00:44 | from Yale in 1977 And my master's Arizona in 1983. And my PhDd |
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| 00:52 | from Arizona in 1987 in structural geology tectonics. Then I spent a little |
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| 00:58 | 30 years with shell international exploration and working all these different bases. |
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| 01:05 | Permian basin, latin, America Bolivia Argentina, unconventional exploration in the US |
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| 01:16 | then looking at reservoir compartmentalization and deep reservoirs. And then for a few |
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| 01:21 | I was manager of two different Classic geology research and development group in |
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| 01:26 | structural geology research and development group. throughout that whole time those shelves, |
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| 01:33 | technical expert in structural geology and taught number of courses like this in structural |
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| 01:45 | . Okay, so these are some the places that I've been Alaska Egypt |
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| 01:51 | Netherlands Malaysia brunei, Nigeria Colombia. was this was a wonderful, wonderful |
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| 01:59 | to be working for the oil This was prior to the advent of |
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| 02:06 | meetings and videoconferences. So to work these different people in different places, |
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| 02:12 | different problems. You had to travel over the world, which was just |
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| 02:17 | . And then, um, why places, all these places, all |
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| 02:22 | places and more depend on oil and revenues to support their social structure and |
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| 02:29 | and gas has gotten a very bad . It's socially unacceptable in the last |
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| 02:36 | the last decade or so. But of these, all of these countries |
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| 02:40 | many more depend on the income from and gas to support their social structure |
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| 02:46 | the Netherlands for example, which is of the most places outspoken against oil |
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| 02:51 | gas exploration. 30% of the government comes from oil and gas production. |
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| 02:59 | in, in in all these other and more as well. It's, |
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| 03:05 | very important to society too producing oil gas and get the revenues from the |
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| 03:11 | and gas in Alaska. Until Every citizen in Alaska. I used |
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| 03:17 | get a check for $700 a year the state from the oil and gas |
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| 03:22 | from Prudhoe Bay. And I put in to show that oil and gas |
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| 03:30 | going to continue To be the the world's main source of energy for |
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| 03:35 | next 30 years at least. Mm . And I have here a projection |
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| 03:42 | Different energy consumption as a function of through 2050. And you see a |
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| 03:48 | here for the collared event but then growth and petroleum and other liquids, |
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| 03:55 | gas renewables pick up tremendously but they pale next to oil and gas for |
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| 04:04 | , energy production and, and, the reason for this is the things |
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| 04:09 | I mentioned, society needs these things maintain our standard of living. |
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| 04:16 | Mm hmm. If you look at of the third world places like India |
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| 04:22 | 100,000 people a year die from indoor from stoves, burning wood dung, |
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| 04:28 | like that. And so oil and are necessary to replace these dirtier sources |
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| 04:35 | energy and and get people on some this extreme poverty that they continue to |
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| 04:40 | in. So you make the point that by supplying the world's oil and |
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| 04:45 | , you're really helping support these helping increase these people's standard of |
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| 04:51 | So, although it's socially unacceptable right , oil and gas production is |
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| 04:57 | very important for the whole world. hmm. And put in this slide |
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| 05:04 | show to emphasize that even TVs require oil and significant oil and gas. |
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| 05:12 | , they need literally tons of oil gas to supply all the plastics and |
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| 05:18 | that go into the s, not mention the hydrocarbons that are required to |
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| 05:24 | the energy to charge the TVs in first place a huge amount of natural |
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| 05:29 | , declining amounts of coal hopefully, natural gas and oil very, very |
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| 05:35 | to supply the energy and the plastics go into all our electric vehicles. |
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| 05:41 | vehicles are a good thing, but not going to eliminate the need for |
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| 05:45 | and gas. But here's the course . It's divided up into nine |
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| 05:55 | The 1st 5 are sort of basic geology things. And they are they |
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| 06:03 | important both for oil and gas exploration for carbon sequestration, mm hmm. |
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| 06:09 | of these basic principles for a stress strain geometry on the mechanics. Top |
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| 06:17 | false heels. These things are equally for oil and gas and for retaining |
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| 06:24 | two when we go to CO two and then these next four topics salt |
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| 06:32 | , full thrust belts, basement Oculus, strikes of death types. |
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| 06:37 | are on the structural styles of each of these types of provinces. And |
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| 06:43 | we'll see is that they're all very for each one of these. And |
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| 06:48 | important to understand the differences when we're our structural interpretations. Thanks and put |
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| 06:58 | this line to emphasize that these topics important for carbon capture and sequestration as |
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| 07:05 | as oil and gas exploration and What any place where we're trying to |
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| 07:11 | C. 02 for storage or for oil recovery. The capacity for co |
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| 07:18 | is going to be controlled by the the topsail capillary entry pressure and the |
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| 07:24 | mechanical capacity. Justice for oil and , lateral steel capacity is going to |
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| 07:32 | controlled largely by faults, seals, , lateral steel capacity, vertical sealed |
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| 07:39 | and fault reactivation potential. So all things that we're going to talk about |
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| 07:44 | false, apply equally to oil and and see co two sequestration. The |
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| 07:51 | difference is the type of fluid and talk about the type of fluid and |
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| 07:54 | inter facial tension, But the basics the same for oil and gas and |
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| 08:00 | two sequestration. Okay, I wanted take a minute to have you each |
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| 08:07 | mute yourselves and just tell us um your current situation is and why you're |
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| 08:13 | the course and Angela, you're on top of the screen so maybe you |
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| 08:17 | um you know, we could start you. I'm um I currently work |
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| 08:25 | a geoscience analyst for a natural gas . Um so I finished my bachelor's |
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| 08:33 | 2020 and I'm in this course to my masters to become a likely developmental |
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| 08:42 | . Okay Dennis can you go Yes sir. So my name is |
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| 08:50 | Dennis Mahon. International student from I go to my undergrad in geology |
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| 08:55 | minors minors in geophysics and mathematics At University of Houston and I graduated in |
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| 09:02 | . Right now. I'm working on masters in geophysics and using this. |
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| 09:07 | trying to get my masters in geophysics well as get my PhD in geophysics |
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| 09:11 | well. So I'm hoping this class going to home improve my knowledge and |
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| 09:19 | aspects and kind of region between structural and geophysical properties. And how do |
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| 09:27 | need to assessment, interpretation an invasion geo phoenix as well. Thank |
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| 09:33 | Okay, good. Um Mcdonald, you want to go next? |
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| 09:38 | Hello everyone. I'm Meghna. I'm international student from India. I've done |
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| 09:44 | Internet in petroleum engineering back in India this is my second minister over in |
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| 09:49 | geology geology program. And I would to acquire the degree in petroleum geology |
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| 09:55 | probably do pursue mine for the job in the sector. Okay, thank |
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| 10:04 | . Well, thank you. Thank all. Mm hmm. Okay. |
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| 10:13 | here's the course schedule of the course what we're going to go through. |
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| 10:18 | today we'll go through the first two on basic principles and structural QA QC |
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| 10:25 | . And then tomorrow it will also a virtual session and we'll talk about |
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| 10:30 | mechanics. We'll take a break for and then go into top seal |
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| 10:36 | We will have a midterm review and final exam at the end of the |
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| 10:44 | . By the time of the we will have covered about 40% of |
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| 10:48 | class. So the midterm will be 40% of the grade And the final |
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| 10:52 | will be worth the remaining 60% of grade. Okay, basic concepts to |
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| 11:02 | two most important basic concepts or definitions of stress and strain. So we'll |
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| 11:08 | about those and then we'll talk about false are organized in structural styles that |
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| 11:15 | related to the stress and the strain there. Mhm. The fault geometry |
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| 11:25 | the subsidizing structure and the stress orientation follow. They all follow certain geometric |
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| 11:33 | geologic principles. So they're not just organized. And then we'll talk about |
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| 11:40 | nomenclature around different fault components, football hanging roll core damage zones. And |
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| 11:48 | the actual geometric rules that defaults follow the fall, it's going to be |
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| 11:53 | as ellipses in shape. The displacement typically a maximum in the middle of |
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| 11:59 | ellipse. They're the length to throw . Our systematic, they vary from |
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| 12:07 | 10 to 100 With a length throw of about 50 is a good |
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| 12:12 | So these already constrained what kind of hmm. Especially in seismic interpretation alone |
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| 12:20 | faults can be and how much displacement can have on the faults, particularly |
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| 12:25 | uh, our seismic volumes. And we'll talk about how false are segment |
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| 12:33 | horizontally and vertically, both laterally and and down. And this is important |
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| 12:39 | linking up the fault during our size interpretation in particular. And for understanding |
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| 12:46 | Kinnah Matic, the displacements along the . And then the last thing we'll |
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| 12:51 | about today are trapped closure elements and factors. We'll talk about the definitions |
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| 12:58 | don't disclose from deep still point topsail and false ego capacity. So these |
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| 13:04 | all the things that will go through . Mhm. The first thing here |
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| 13:12 | stress that stress is defined as force unit area and it's the units are |
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| 13:19 | per square inch C. Or bars pascal's. And this is the conversion |
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| 13:24 | to go back and forth between. see what we call oilfield units and |
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| 13:29 | or pascal's metro units. And then stresses. We have three principal stresses |
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| 13:38 | one which is the maximum stress Segment which is the intermediate stress In Sigma |
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| 13:44 | which is the minimum stress. And we also have sigma V. Which |
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| 13:52 | the vertical stress signaled H the maximum stress and sigma small age, the |
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| 13:59 | compressive stress. And depending on which of these, which one of these |
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| 14:05 | is sigma. One determines whether we normal faults or reverse falls or strikes |
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| 14:13 | . And I've shown here a cube get the ideas across a sigma V |
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| 14:18 | typically a rogue easy, rogue So this is the just the weight |
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| 14:23 | the overburden, the weight of the . Com that's our typical vertical |
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| 14:29 | And then we have the maximum horizontal which may be more or less than |
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| 14:34 | V. When this is greater than V. Then we get thrust faults |
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| 14:40 | reverse falls. Oh and then we the minimum horizontal stress. The signal |
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| 14:47 | age which also maybe creator or less sigma V. And when it's less |
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| 14:53 | significant is when we get normal false strain strain is defined as the change |
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| 15:06 | length in response to the applied It's defined as the the change in |
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| 15:13 | divided by the initial length or final minus initial length divided by the initial |
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| 15:20 | . So LF myself zero divided by zero. And we'll use this to |
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| 15:26 | strains various exercises through the rest of course. And just like the stress |
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| 15:34 | strain is divided into E one 23. E one being the maximum |
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| 15:42 | or extension he to being the intermediate extension, Any three being the minimum |
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| 15:48 | extension. And these are represented in of change in shape from an initial |
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| 15:57 | into what's called a strain of limps The one is the maximum dimension and |
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| 16:03 | three is the minimum dementia. And he here for example to form trilobite |
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| 16:09 | basically been squashed. Mhm. And a strain is important because strain is |
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| 16:15 | that we can measure in the And stress is something that we can |
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| 16:21 | present day. But we can't measure geologic time scale. So we can |
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| 16:26 | tell what stresses are going to apply Iraq's but we can always tell what |
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| 16:32 | have resulted what changes in shape have from the stress is applied to the |
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| 16:42 | . Okay, so stress orientations determine basic fault shape. The basic fault |
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| 16:50 | And faults or shear fractures typically form about 30°. to signal one the maximum |
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| 16:57 | and um if signal one is vertical signal one is the vertical stress And |
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| 17:04 | get a 60° nor rainfall normal fault by this guy around. So signal |
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| 17:11 | equal signal line. Signal each man Sigma three. And we get normal |
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| 17:17 | with football here and the hanging wall in the program. If we flip |
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| 17:24 | one and signal three, so that V. Is the minimum horizontal stress |
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| 17:30 | signal aah max is the maximum horizontal . This is where we get reverse |
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| 17:37 | or mhm or your reverse bonds of faults Dipping at 30°. So 30° orientation |
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| 17:46 | signal one here, the normal falls about 60 degrees also 30 degrees to |
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| 17:53 | one. But because Signal One is to get a 60 degree dip Whereas |
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| 17:57 | , when signal one is horizontal, got a 30° dip. And then |
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| 18:03 | we get a strike slip faults when one Signaled H. Max. Even |
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| 18:11 | one. Sigma three is the minimum here. And the intermediate stress sigma |
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| 18:20 | is sigma two. And the strike falls again form in about 30 degrees |
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| 18:26 | signal one, But now they dip rather than 30 or 60°. They still |
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| 18:35 | an angle with 30° with signal But they did vertically because their strikes |
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| 18:40 | falls okay. And then with with normal faults, we typically get these |
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| 18:50 | and grubbing structures where the the the uplifted blocks, the province are |
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| 18:55 | down list down dropped block and the is the uplifted side. In the |
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| 19:03 | wall in both cases is the down side. But here's some block diagrams |
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| 19:12 | the orientations of the stresses in the . Well, again, with normal |
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| 19:18 | we have the 60 degree dibs one vertical sigma, three horizontal sigma |
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| 19:25 | intermediate parallel to the strike of the . When we flip signal one and |
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| 19:31 | three, we get thrust faults, faults From 30 degree reduced horizontal |
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| 19:38 | Sigma three is vertical and Sigma one horizontal. With strike slip fault We |
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| 19:46 | again so that the stresses, both one and sigma through your horizontal. |
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| 19:52 | And we get these strike slip faults 90° dips and um oriented about 30 |
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| 19:59 | to sigma one. And we get horizontal shortening in horizontal extension in the |
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| 20:07 | orientations relative the faults with structures that given shortening in this direction and extension |
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| 20:14 | this direction of Carolina stigma three. , so these fault types and strains |
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| 20:29 | tectonic environments With normal faults, we the 60° tips. We get horizontal |
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| 20:36 | and we get these mid ocean ridges rift margins and continental passive margins. |
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| 20:42 | like these formal falls, dominate all all the active structures in Nigeria for |
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| 20:51 | . Okay, Reversers faults with the dips horizontal shortening. The football here |
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| 20:59 | the hangar, on the up thrown represents horizontal contraction. And we get |
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| 21:06 | at convergent margins, Transgressive margins thrust and deepwater and ultra deepwater full thrust |
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| 21:13 | . So I'm like all the toad in deepwater Nigeria. Okay, Strike |
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| 21:19 | faults shown here 90° Tibbs displacement parallel the fault. We had both horizontal |
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| 21:27 | horizontal uh contraction and extension and they're in this oblique angle to the actual |
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| 21:37 | slip displacement. And then we get at strike slip margins and transforms also |
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| 21:44 | SAn Andreas fault system, for is probably the most widely known, |
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| 21:48 | widely recognized. Now there's a third of fault that we didn't recognize until |
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| 21:57 | advent of three D. Seismic data we could see seismic time slices. |
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| 22:03 | what we're looking at here is a time slides but it's from offshore |
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| 22:09 | Deepwater Norway and all these things that looking at are false. And you |
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| 22:16 | there they look like they look like cracks. Um And they're called they're |
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| 22:21 | political falls and they really are seismic mud cracks. This is an example |
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| 22:33 | those faults in cross section seismic section 50 milliseconds here for time. And |
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| 22:41 | see the faults here. All these are these political faults in plan view |
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| 22:47 | you see they die out upwards and die out downwards and then in these |
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| 22:53 | layers you get other sets of of out faults. We'll talk about this |
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| 22:58 | fractures but them we're seeing an example mechanical strategic fee here where we have |
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| 23:05 | set of political faults in these layers another set in these layers and then |
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| 23:11 | in these in these deeper layers. the way this form is by a |
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| 23:22 | called scenery sis. And the idea that the the vertical vertical load causes |
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| 23:32 | compassion and de watering and the de leads to contraction in the horizontal directions |
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| 23:40 | well as the vertical directions. So squashed the things vertically. But they |
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| 23:46 | contract in the horizontal direction as And we get all these little normal |
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| 23:53 | That link up in polygonal patterns in days. What? And these are |
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| 24:00 | are typically associated with fluid escape chimneys sand. Inject types and things like |
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| 24:06 | . Mm hmm. For example, you go back to this this |
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| 24:11 | we're looking at this time slice of falls, we have all these political |
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| 24:16 | . And then we have a mud here in the middle of Mhm. |
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| 24:21 | volcano of fluid expulsion feature here in middle of all these pulling in faults |
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| 24:27 | from the compassion and the fluid Mm hmm. So the stress orientations |
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| 24:38 | political falls as I've mentioned, Signal is sigma v. Signal one is |
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| 24:45 | and then sigma two and sigma three about they're both in the horizontal plane |
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| 24:51 | they're about the same magnitude which is gives us this polygonal pattern. The |
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| 24:58 | contract. The rocks contract, but the horizontal direction equally in this direction |
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| 25:06 | in this direction generating this. Pulling on mud, mud, crack black |
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| 25:17 | . Okay, and as I these were never recognized until we got |
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| 25:23 | sizing crime slices and now they're recognized basins pretty much all over the |
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| 25:30 | along the east coast of the gulf Mexico, up in the truck. |
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| 25:35 | see here down off Argentina and brazil the west coast of Africa, the |
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| 25:43 | coast of Africa, mm hmm Up in the north sea, up here |
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| 25:48 | the north seas where they were first and then in the Okanagan basin of |
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| 25:54 | Australia here in other basins around Australia New Zealand. We we think that |
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| 26:02 | requires a particular type of clay to these political falls and that's probably why |
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| 26:09 | , why they occur in these particular of bases. Yeah. Now, |
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| 26:18 | for oil and gas production, one the political falls to actually help oil |
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| 26:24 | gas production. I'm showing here a a structured contour map of the Ormen |
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| 26:35 | gas field offshore in Norway. And all these lines, these light train |
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| 26:40 | represent political falls and it looks like reservoir should be very highly compartmentalized and |
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| 26:47 | it would require it uh a well for each one of these compartments |
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| 26:53 | produce the whole thing. But in , because these following the fall to |
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| 26:59 | low throw what they do is they communication. So I have a cartoon |
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| 27:04 | section here with the fault and different beds here on the down thrown side |
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| 27:11 | here on the out thrown side in political false result in juxtaposition of all |
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| 27:17 | rust war beds and so during all these restaurant vets are in communication |
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| 27:23 | each other across these faults and the actually enhanced communication rather than detract from |
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| 27:38 | . Okay, basic fault components. fault terminology. Well, the two |
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| 27:43 | important things are the football and the the football is shown here, the |
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| 27:49 | blog for these normal falls. The wall shown here where the foot wall |
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| 27:56 | the fault is you get a It's called geometrically, it's a line |
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| 28:01 | we call it the football cut Similarly on the hanging wall without hanging |
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| 28:06 | bed intersects the fault. We get line of intersection that represents the pain |
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| 28:11 | cut off in these. The football off from the hanging wall cut off |
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| 28:16 | typically what we represented in our particularly in our size maps made from |
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| 28:21 | data. This would be the default that you see on your on your |
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| 28:27 | comes from apps. Mm hmm. fault throw is the vertical component of |
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| 28:37 | along the fall. So it's a different than the true displacement parallel to |
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| 28:42 | fall. The fault throw is just vertical component without displacement. Hmm. |
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| 28:55 | right. Now, in sort of D. Here we have additional fault |
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| 29:00 | . So I'm showing one horizon another idea horizon here in a |
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| 29:09 | a structured contra mat at the bottom the diagram here. So you can |
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| 29:13 | the default here in here On off the horizon similarly offsetting this deeper horizon |
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| 29:23 | so that the pink things are my whether offset or where the fault |
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| 29:28 | This stippled pattern is the fault and actual displacement is the displacement from the |
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| 29:37 | cut off to the hanging wall cut parallel to the fall. Mm |
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| 29:43 | And in Matthew that represents my fault down here and the width of that |
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| 29:51 | gap represents what's called the heave on amount of you. Now the faults |
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| 29:58 | extend forever. So in in vertical , the faults eventually die out. |
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| 30:05 | that edge of the fault is what's the tip line. That's the tip |
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| 30:09 | the fault. And this is a session where all this information is projected |
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| 30:15 | the vertical session. You see the line here. Mm hmm. The |
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| 30:22 | cut off here and the hanging wall off here And that displacement between the |
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| 30:27 | represents the Throat. Okay, now we're looking at a structure concert |
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| 30:44 | It's colored by elevation contours represent the contours and they're in, I don't |
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| 30:54 | there are 50 ft 50 ft increments in this, this black gap in |
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| 31:01 | view is the default gap where that tips out is the fault tip line |
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| 31:08 | plan is from here. This is football cut off here in the up |
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| 31:13 | side. The hanging roll cut off on the down thrown side. And |
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| 31:18 | any point along this fault, we get throw approximately displacement from the difference |
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| 31:25 | contours across here. So here I've a M. A 600-foot contour on |
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| 31:32 | up front side, The 425 ft on the downtown side. So that |
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| 31:38 | tells me that the throw is about ft at that point on the |
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| 31:44 | And as I go in different as I go this way, That |
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| 31:48 | increases as I go towards the fault that eventually decreases to zero mm |
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| 31:55 | And this, this ability to get fault throw and sense of displacement from |
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| 32:02 | contours that hit the fault. It's important principle that we use through a |
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| 32:08 | of QA QC exercises now along the . We also have what are called |
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| 32:18 | organs. And the idea is that faults are are zones and not just |
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| 32:26 | plain and discontinuities, like like we its seismic. So what we see |
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| 32:30 | seismic is really an oversimplification of what looks like. All right. So |
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| 32:36 | , I've got a three dimensional but the fault is kind of a |
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| 32:40 | shaped here. The main slip zone here. This is what's called the |
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| 32:47 | of the fault. This is where get a fault gouge and the main |
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| 32:52 | service. And then adjacent to we have an inner damaged on where |
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| 32:57 | have lots of interconnected little faults and and then an outer damage zone here |
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| 33:05 | we go, okay, must we a much less intense zone of small |
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| 33:12 | and fractures? Yeah, these are these faults and fractures are important for |
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| 33:22 | steel capacity. And when we start about cross fault, flow and flow |
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| 33:27 | and around these faults. Okay, here's a cross section showing these. |
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| 33:37 | definitions are cartoons again. So, have my football of thrown fault block |
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| 33:43 | . Down thrown angle blocks here. main fault core slip surface here, |
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| 33:50 | in the middle and then adjacent to , we have a damage zone with |
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| 33:57 | of small faults and fractures. And we go away from the main |
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| 34:02 | the intensity of these small faults and dies out. It also varies up |
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| 34:08 | down the fall. So here, example, we have a layer with |
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| 34:13 | fairly high intensity. Damn it Whereas in these other layers we have |
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| 34:18 | or no damage, no development at . So, here's an example from |
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| 34:31 | . Here's the main fault going through . This is my main slip plane |
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| 34:37 | fault core. You can see this is offset down, thrown here on |
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| 34:43 | side. And up here in this brittle layer, you see a lot |
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| 34:49 | faults and small faults and fractures Whereas in here, where you have |
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| 34:53 | more ductile layer, we don't see small faults and fractures are very, |
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| 35:00 | much less develop faults and fractures. right, we're going to talk about |
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| 35:12 | geometric rules that false followed or that can be approximated as ellipses with the |
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| 35:17 | greater than the height. The thrower is maximum in the middle. The |
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| 35:23 | throw ratio varies from 10 to 100 Typically it's about 1550 is a group |
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| 35:31 | approximation of the length relationship, mm . And since sedimentary and slice landfalls |
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| 35:37 | different lengths, throw ratios, I'm on the amount of trigger demanding on |
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| 35:42 | amount of growth during the, during faulting. Okay, so I mentioned |
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| 35:52 | fault displacement varies that the faults are shape. We see that here in |
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| 35:59 | mm hmm. With the fault pain will cut off here down thrown |
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| 36:06 | cut off here increasing displacement from left right Our Fault Tip. zero displacement |
|
| 36:14 | displacement increasing to the right, mm . And then in this case with |
|
| 36:19 | creation showing the pure dip slip nature fall. So this is a throw |
|
| 36:33 | for a single fault. So, looking at a vertical plane where we've |
|
| 36:38 | the hanging on the floor onto the . So it's a single fault. |
|
| 36:43 | fault is represented by this sort of color here. This is the football |
|
| 36:49 | off here. This is the hanging comin off here sort of sing clonal |
|
| 36:56 | And the throat decreases from zero at tip To a maximum somewhere towards the |
|
| 37:03 | of the fault and then decreasing again zero. It's a tip over |
|
| 37:08 | Mm hmm. So here's a throw for such a fault where we can |
|
| 37:25 | at multiple horizon offsets to get these of throw profiles for multiple horizons. |
|
| 37:35 | that gives us these throw contours where have the tip line here with zero |
|
| 37:43 | And then increasing displacement 10 2030 But as we get towards the, |
|
| 37:50 | the center of the fault. Mm . And so the fault of role |
|
| 37:55 | elliptical in shape and the throat decreases laterally from the center towards the |
|
| 38:02 | Aaron vertically from the center towards the and towards the base. And here's |
|
| 38:15 | here's a seismic example. Here's a cross section. You see the phones |
|
| 38:21 | and by looking at the offset of horizons here, we can create this |
|
| 38:26 | contour diagram that shows the throw as highest here in the middle of the |
|
| 38:32 | , Decreasing to zero at the tip , both vertically and horizontally as we |
|
| 38:39 | along the strike in the fall. In the the length to throw |
|
| 38:46 | But it varies from 10 to 100 typically 50 is a good approximation. |
|
| 38:54 | If your throw is about 50 you expect your fault to be about |
|
| 38:59 | kilometers or 2500 m long. So is an important constraint we can use |
|
| 39:05 | our fault interpretations, particularly in seismic . Alright now this, this is |
|
| 39:16 | plots showing those relationships. So here have for like and here I have |
|
| 39:23 | maximum displacement that displaced at the center the fault zone. And each one |
|
| 39:28 | these lines represents a ratio of one Like throw one length to throw of |
|
| 39:38 | , Like to throw off 100 lengths throw over 1000. So you can |
|
| 39:42 | there's a lot of scatter in But this red line of length to |
|
| 39:47 | 50 is a pretty good average of the data that we get in here |
|
| 39:53 | these different colors represent different types of . And you see they all form |
|
| 40:00 | pretty much the same rules. Mm . So there's The rule of thumb |
|
| 40:06 | 9th 50 times the displacement is applicable normal faults, reverse faults of strikes |
|
| 40:12 | false equally. Mhm. And so this diagram, If you know your |
|
| 40:21 | is about 50 m at one You can extrapolate that over to the |
|
| 40:26 | dimension line and see that you what expect your fault lengths to be. |
|
| 40:32 | the fault length of 50 m. expect the fault length to be about |
|
| 40:36 | times that about 2500 m. so here's here's sort of a discussion |
|
| 40:46 | here. Um we're looking at a . Conn dramatic from seismic data in |
|
| 40:52 | incline trending through here and then a of small falls crossing that incline at |
|
| 41:03 | point along these faults. The displacement Is less than about 50 m. |
|
| 41:10 | right at our seismic reservation. And interpreted here is a 10 kilometer long |
|
| 41:17 | with a 15 m displacement based on we just talked about. Is that |
|
| 41:27 | ? Mm hmm. So what I you to do is take it Take |
|
| 41:35 | 50 m dimension. Go back to previous lives and see what kind of |
|
| 41:43 | displacement I would expect on there. anybody is welcome to speak up. |
|
| 42:11 | use that that 1-5 ratio that we about is the slip the same as |
|
| 42:49 | displacement. Yes, the slip is same as the displacement. So it |
|
| 43:26 | be closer to the 100 D. . It would be, you |
|
| 43:35 | it would be much closer to 100 . Line. All right. So |
|
| 43:48 | we had 10 kilometers with 50 m , it would be, yeah, |
|
| 44:05 | would be close to this Between the and the 110 delight. I'm |
|
| 44:13 | No, no. I meant that wrong way. It would be |
|
| 44:16 | It would be right around the 100 deadline. So it would be statistically |
|
| 44:22 | unlikely so more likely. What we're at here is um, A smaller |
|
| 44:44 | of false where we have 50 m which is something that we can |
|
| 44:51 | Reliably in the seismic profiles and with with this structure contour map These red |
|
| 45:03 | represent intersections of the fault ticks with horizon and making it one fault implies |
|
| 45:12 | 10 km long, which is statistically . What's more likely is that you |
|
| 45:19 | a series of small faults here that closer to closer to 2500 m in |
|
| 45:26 | . So probably one fault here with gap here, Another fault here with |
|
| 45:32 | throw about 50 m and a gap over here where the fault picks were |
|
| 45:37 | . So when we're interpreting the seismic , you see a series of thoughts |
|
| 45:43 | this, it's important to say look the time slices and identify what the |
|
| 45:50 | length of the fault is and where have a series of segments of individual |
|
| 45:56 | , this being one, this being and so on. Yeah, similarly |
|
| 46:01 | here, if we look at this fault, you probably have one small |
|
| 46:08 | there, another small fault there and the third fault there where it changes |
|
| 46:13 | and by looking at a seismic time , you can you can distinguish this |
|
| 46:21 | more easily. Really more questions or on that before we move on. |
|
| 46:49 | , that's what we just talked Okay, why don't we? Um |
|
| 46:56 | been going for about Just under an . We could go about 50 |
|
| 47:00 | So why don't we take a five break here. Mhm. Going to |
|
| 47:04 | around, get them and get a , Wake up, get the blood |
|
| 47:09 | again and then we'll come back in minutes. Yeah. So the point |
|
| 47:17 | want to talk about now is that . Core thickness is related to the |
|
| 47:22 | . Just like the displacements will related the throat. The thickness is related |
|
| 47:27 | the throne. And what's shown on cross plot are fault displacement from the |
|
| 47:34 | axis, fault thickness for the Y . And you see this trend Through |
|
| 47:41 | where the green line is one 1 1000. Red is 1 to 100 |
|
| 47:48 | blue is 1 - 10. And 1 to 1 to 100 is a |
|
| 47:54 | rule of thumb for the relation between thickness and the displacement. So here |
|
| 48:00 | a fault and outcrop and with the zone shown here in blue and that's |
|
| 48:07 | we mean by the false um, the width of this. This horizontal |
|
| 48:14 | a, here's another example of that And you see the fault zone core |
|
| 48:19 | , through here with his white ground counter clay site material represented the highest |
|
| 48:26 | and this This thickness is a function the throw of the entire fall and |
|
| 48:32 | false with large throws are wider or than false with small throws john In |
|
| 48:38 | good rule of thumb is that thickness is 1 100th of the fault |
|
| 48:44 | And it's this is especially important for at cross fault flowing reservoir models looking |
|
| 48:51 | resort compartmentalization and things like that on production side for those production problems, |
|
| 48:57 | really need to know that with of low permeability zone. With of |
|
| 49:03 | All right. With that thought Mhm. Okay. So here we |
|
| 49:11 | in on that plot with fault displacement , fault core thickness here and |
|
| 49:19 | This red line representing 1 to 100 a good average of the like throw |
|
| 49:27 | ratio. Okay, okay. So this can come. This becomes important |
|
| 49:35 | wrestling models but also can become important relating to things you see in core |
|
| 49:40 | the signs we get it. So , I've got an example of the |
|
| 49:45 | , but with a fault in it , you see the other side of |
|
| 49:48 | fault here. The gods own for , there's Fault is about a half |
|
| 49:54 | thick. So five .005 m Would you consider this a seismically resolvable |
|
| 50:27 | ? No, sir. No. , that's right. Exactly right. |
|
| 50:31 | , so if it's, If it's m thick on this cross plot, |
|
| 50:37 | would be down here On 30.005. you would expect that fall to have |
|
| 50:43 | displacement, you know, less than meter between mm hmm The 10th and |
|
| 50:52 | 10 m at most. And so is not something you would see in |
|
| 50:56 | seismic data unless you have very high seismic data. Okay, yeah. |
|
| 51:08 | Here we have the cross blood, m Hitting 1 200 line. We |
|
| 51:15 | the displacement to be about 0.5 And so not something that we would |
|
| 51:21 | seismically unless you had exceptionally high resolution data. Mm hmm. Okay. |
|
| 51:31 | next thing I want to talk about that false? Are segmented both horizontally |
|
| 51:36 | vertically. And remember that we talked the fall tap of the tip line |
|
| 51:40 | surrounds the outer edge of the And that that defines how we get |
|
| 51:48 | different fault segments and how they, they organize themselves. Okay. And |
|
| 51:59 | , this is very important mostly for very important for sizing interpretation that many |
|
| 52:04 | on a single plane, many false , discontinued consumer segmented. And so |
|
| 52:11 | is a cross plot of distance along fault versus displacement For 1, |
|
| 52:18 | 3, 4 different faults. When you see one this fault has |
|
| 52:24 | displacement profile like this. This fall a displacement profile shown like the green |
|
| 52:30 | here and the blue fault here. displacement shone like this. So these |
|
| 52:38 | visual falls don't really link up But in fact if we saw these |
|
| 52:43 | seismic data, we would interpret them 11 fault with the maximum displacement somewhere |
|
| 52:49 | it here. Okay. And these , these segments give rise to what |
|
| 53:01 | call relay ramps. So here's a an outcrop scale example with one fault |
|
| 53:08 | here. A second fault segment They overlap here with unfolded portion |
|
| 53:17 | It's called a relay ramp. this is another example if you've ever |
|
| 53:24 | out too long mobile and hiked out delicate arch. The trail too delicate |
|
| 53:29 | goes up this relay ramp. So have one fault Here with about 10 |
|
| 53:35 | displacement. Another fault here we're sort 10 or 20 m displacement tip line |
|
| 53:42 | and tip line here and then this ran in between the two different false |
|
| 53:55 | . And so in this block I'm showing the definition of a relay |
|
| 54:00 | Sort of one Fault here, hanging cut off football cut off tip line |
|
| 54:09 | , you know involved in segment in . And then another false statement here |
|
| 54:14 | the hang or cut off the football off tip line here and the sudden |
|
| 54:20 | relay ran in between. And this well, a ram geometrically serves the |
|
| 54:28 | the displacement between these two fault hence the name relay ramp. |
|
| 54:39 | Okay, so here's, here's an from Ethiopia from the Ethiopian rift |
|
| 54:44 | a whole series of normal faults. normal fault here. Another phones here |
|
| 54:51 | a really rampant between one that's slightly in this case and again, so |
|
| 55:05 | see one fault here, another false . The tip here, the tip |
|
| 55:14 | , the relay ramp in between the fault in the middle of really ramp |
|
| 55:20 | here, we have a jog in fall. Well maybe you can see |
|
| 55:24 | better in this one where the where segments have actually grown together, creating |
|
| 55:31 | little job in the fall. So this case the relay ramp has been |
|
| 55:36 | through so that these two segments join and that gets us to the idea |
|
| 55:46 | an intact relays on versus a breached zone. So we have two schematic |
|
| 55:53 | here on the upper one here we hanging on the football in a relay |
|
| 56:00 | between it is unfaltering. So the all cut off the football kind of |
|
| 56:07 | there, no, the tip the other hanging wall cut off the |
|
| 56:11 | cut off with this unfolded relay ramp between with increasing displacement. Eventually this |
|
| 56:19 | faulted through and give us a breached . Oh, so now I have |
|
| 56:25 | continuous hanging while one continuous hanging, continuous football and one segment at football |
|
| 56:34 | off going along here here and here this relay ramp is now why it's |
|
| 56:40 | faulted through or breach so that we a breached relay song. And this |
|
| 56:47 | becomes important for for fluid flow and trapping. In a case like |
|
| 56:55 | this relay Rampal served as a leaked running down from accumulation on this side |
|
| 57:02 | this side. Whereas here you can a continuous accumulation since that fault has |
|
| 57:09 | off communication between the hanging wall and football and so here's another, here's |
|
| 57:20 | photo from the relay ramp in arches Park on the way up to delicate |
|
| 57:26 | , you see fault Eddie here with wall cut off the football cut off |
|
| 57:31 | applying there, thought I'd be here the hanging wall cut off, we'll |
|
| 57:36 | it off and then an intact relay in between. That's going to allow |
|
| 57:43 | fluid on this down front side, it be here or here to spill |
|
| 57:47 | up along this freeway ramp and this an example from the same area of |
|
| 57:58 | breached relay ramp where we have fault going here fault be extending here And |
|
| 58:06 | a relay ramp extending between the But in this case the fault cuts |
|
| 58:11 | it and breaches the relay around and off communication between these these two pain |
|
| 58:20 | and football and in the block diagram , um I have a block diagram |
|
| 58:27 | a relay that's preached that wanna you also have realized that are breached at |
|
| 58:32 | ends, both on the down thrown in the throne side in both |
|
| 58:38 | separating the ultimate football from the ultimate role. Okay, alright, this |
|
| 58:49 | to the idea of conservation of throw I'm showing here too, two different |
|
| 58:58 | to faults, segments um with a really ramping between here. But the |
|
| 59:05 | here is that the throw at this , see equals the sum of the |
|
| 59:10 | on a and the throne on being and again, in seismic interpretation, |
|
| 59:16 | becomes important for correlating europe throwing down horizons firms, you have to pick |
|
| 59:23 | horizon where these, The two small equal equal to Big Throat. Here's |
|
| 59:35 | block diagrams illustrating that. So in , this first one, I have |
|
| 59:40 | blockade here. If I go down ft of throw heat here, That's |
|
| 59:50 | . I'm sorry. That's 200 ft throat, go down 200 ft of |
|
| 59:54 | here. I come over here. have that 200 ft of throat is |
|
| 59:59 | into 100 ft and 100 ft So that total displacements here equal the |
|
| 60:06 | displacement on the big fault here. . In Matthew I have to synthetic |
|
| 60:14 | here with 150 m displacement here, m displace right here In 200 m |
|
| 60:21 | here. So if I were to around that side Down 150 m |
|
| 60:27 | 150 m, then up 200 m get back to where I started and |
|
| 60:32 | the idea that the throne is conserved this set of fault intersections. Now |
|
| 60:38 | shows the synthetic falls for an genetic , although it's a little different. |
|
| 60:45 | , Here I've got 150 m through here. I got 50 m thrown |
|
| 60:50 | And that equals 200. We just . Were these two faults merged. |
|
| 60:56 | if I were to walk around I would go Down 150 m |
|
| 61:00 | 150 m and up 200 m get to where I started along this |
|
| 61:12 | Okay, so here's some other examples that with synthetic faults. 300 ft |
|
| 61:18 | , 300 ft down equals 600 ft . Where these two faults merged for |
|
| 61:25 | falls Go down 600 ft down, ft and up 1000 ft. So |
|
| 61:35 | 600 ft down plus 400 ft down this 1000 ft down for antibiotic |
|
| 61:43 | creating a horse here. This created grab in. We've got a |
|
| 61:48 | Mm hmm. So here, we've 600 ft of throat here. |
|
| 61:55 | Equal to 300 ft of Throat here 300 ft of throat here. So |
|
| 62:00 | I were to walk around this, would go down 600 ft. Come |
|
| 62:04 | here. Go up 300 ft come here and go up another 300 ft |
|
| 62:08 | get back to where I started across from scaling of relay ramp dimensions. |
|
| 62:21 | , All right. You see what plotted here is separation versus transfer |
|
| 62:31 | So in this Matthew, this is separation. This is what's product here |
|
| 62:37 | transfer throne, which is the mm . Change in displacement between these two |
|
| 62:45 | and either one of the tip And the idea is that this this |
|
| 62:55 | with versus length of the relay ramps be more or less proportional and it |
|
| 63:02 | crudely is um, but there's no between, there's no consistency on whether |
|
| 63:11 | relays are intent or preach in this plot intact ramps are shown here with |
|
| 63:19 | hollow symbols, breach tramps are shown where the filled in symbols. Um |
|
| 63:26 | they all they all follow basically the trend between separation and throw across |
|
| 63:32 | Um So we can't we can't use with length dimensions to constrained whether these |
|
| 63:42 | ramps are breached or not. And , so vertical segmentation, we've been |
|
| 63:54 | about horizontal segmentation. We also see segmentation particularly in seismic data. So |
|
| 64:03 | I have vertical size and profile un and interpreted here. And you see |
|
| 64:11 | you look closely that the displacement along segment actually dies out at this |
|
| 64:17 | And then it's relayed or picked up another fault going down through here. |
|
| 64:23 | when we're interpreting seismic data we typically blast through this with a single fault |
|
| 64:29 | of single false interpretation when in fact a it's not actually to false when |
|
| 64:36 | separated with tip line here and tip here, an area of no throw |
|
| 64:41 | between and again. And for looking trying to determine whether this is a |
|
| 64:47 | fault zone or not. That vertical point is going to form a link |
|
| 64:53 | These two faults across these two falls as the false grow these segments become |
|
| 65:02 | in this. This cartoon shows the here, you start out with initially |
|
| 65:09 | falls and as they grow, the line expands in the intersect so eventually |
|
| 65:17 | four faults can become one large fault this would throw minima sort of in |
|
| 65:23 | middle of the fault. Similarly here these little falls, if you start |
|
| 65:31 | with three segmented falls as they these faults are going to link. |
|
| 65:37 | . Go away. Where'd that come ? Mhm. You end up with |
|
| 65:42 | large fault, the throne minimum in upper and lower thirds of the false |
|
| 65:55 | . Alright, so this this is sandbox model showing how these, how |
|
| 66:00 | faults grow and evolve. So we three, we have one model at |
|
| 66:06 | different stages of extension With extension increasing stage 1 to Stage 2 to Stage |
|
| 66:13 | . And in the first minimal extension see little bits of the fall little |
|
| 66:20 | segment here, a little false segment . Little fault segments here here and |
|
| 66:26 | as these as the extension increases, segments linked up so that these three |
|
| 66:32 | become, there's actually one through going there. And as they continue to |
|
| 66:41 | the tips extend further this way and this way and start to link up |
|
| 66:47 | fault with this fault. So this is this fault on stage three and |
|
| 66:53 | about to be linked up with this here. Right now we've got a |
|
| 66:57 | relay ramp in between here and this about to become a breach relay ramp |
|
| 67:01 | the extension continues in this fault continues grow and merge with this fall |
|
| 67:08 | we'll see the same thing at this . It's his fault segment grows and |
|
| 67:13 | this segment here. Um, So is this is another view. Oh |
|
| 67:26 | . The increasing fault coalescence with increasing . So here I've got a |
|
| 67:33 | horizontal extension about 2.5% here. I It's increased to three here. I |
|
| 67:40 | three fault segments. Fs one FS NFS three. And now with this |
|
| 67:47 | of a 1/2% strain, these three emerged. FS one merged with FS |
|
| 67:54 | FS 3 all along through here. this shows her the throw profiles for |
|
| 68:10 | series of coldness phones that we just about. Here's with the 3% strain |
|
| 68:16 | the falls have just linked up. I have always initially one phone. |
|
| 68:20 | folds. Three folds four folds, folds across here that have linked up |
|
| 68:26 | a minimum amount of throw at each of these intersections. His extension |
|
| 68:32 | These faults grow. They extend laterally both dimensions and the displacement increases, |
|
| 68:40 | hmm. And the throw increases at minimum. But these minimums still stay |
|
| 68:47 | small compared to the rest of the continued extension, the fault grows even |
|
| 68:56 | . The extension increases and the throw in this direction and I still preserve |
|
| 69:02 | thrown minimum Lara, the different points the fault where these faults originally |
|
| 69:10 | So overall the fall through profile is or less elliptical but it's going to |
|
| 69:18 | minor second order variations from where all false originally emerged. What? |
|
| 69:40 | so all those faults segments we're looking , we're just in normal faults. |
|
| 69:45 | see the same thing with thrust And here we're looking at a mhm |
|
| 69:53 | horizon along a series of thrust Deepwater toe thrust in this case And |
|
| 69:58 | see there's one culmination here, the culmination here with a ramp in |
|
| 70:06 | So these are two different segmented thrust . Similarly here We see one an |
|
| 70:14 | here, a ramp here and another a coin here with a small ramp |
|
| 70:20 | between Here on this third trend. see the same thing with one |
|
| 70:25 | one and a calling and one fault ramp here and another. An incline |
|
| 70:30 | to pick off here. Mm And so these these falls are segmented |
|
| 70:37 | horizontally and and vertically. Mm And depending on the step overs, |
|
| 70:48 | , where, where, where this is moving this way. And this |
|
| 70:53 | is when we know where you get zone of extension in between these. |
|
| 70:57 | you may see minor normal faults and in these wheeling ramps in between the |
|
| 71:04 | different sets here where this block is this way and this block is going |
|
| 71:11 | the left. When you got a of contraption in between here and you'll |
|
| 71:16 | minor oblique thrust faults and reverse faults in this area of overlap. All |
|
| 71:29 | . Um, I want to talk different closure definitions. So here I |
|
| 71:36 | a schematic cross section. Mm Up thrown fall trap. There's my |
|
| 71:43 | seal. My my Christopher horizon is here. Mm hmm. And the |
|
| 71:51 | ultimate spill point is here. This obviously is the crest. This is |
|
| 71:59 | ultimate spill point here. Between between the crust here and where the |
|
| 72:07 | bed first. It's the fault. have a closure that's just dependent on |
|
| 72:12 | . That's just dependent on dip dependent . So, this is my this |
|
| 72:17 | my least risky closure. Below this , I can still trapped hydrocarbons, |
|
| 72:25 | hmm. But now I'm dependent on hell along here. So this now |
|
| 72:30 | my fault dependent closure. The total dependent closure goes all the way down |
|
| 72:38 | to the elevation of my ultimate spill . If I fill this with |
|
| 72:45 | the oil water contact or gas water may not come down this far. |
|
| 72:50 | made for me will want to contact free water level somewhere here. |
|
| 72:56 | in that case, my total column goes from the crest to this free |
|
| 73:03 | contact. It's under Phil and relative the total dip point when total closure |
|
| 73:09 | from the crest to the dip skill , but my column height only goes |
|
| 73:15 | the crest to that gas water So in some cases the total column |
|
| 73:21 | maybe less than the total closure. , so this is what the same |
|
| 73:30 | looks like in Matthew. There's my my crest, you're my structure contours |
|
| 73:37 | 100 m contour interval fault cut off . Up, thrown side here, |
|
| 73:43 | , thrown side here. Mhm. dip closure extends from the crest down |
|
| 73:50 | the first contour that hits the So in this case it would go |
|
| 73:54 | crest to 50 down to a Tip of about 300, maybe 3 25 |
|
| 74:02 | sphere down to where the first contour is the fault below that, Below |
|
| 74:07 | 300 m contour, I'm dependent on ceiling dependent on the fault, impending |
|
| 74:13 | . And that goes from that last contour of 300 m Down to my |
|
| 74:19 | point of 550 m. So my dependent closure goes from there down to |
|
| 74:25 | intermediate contour. They would be extrapolated the 500 and 600 m contour. |
|
| 74:33 | right. And this, this disclosure my lowest risk. My fault dependent |
|
| 74:39 | independent on faults feel. So that the a slightly greater risk. And |
|
| 74:46 | this bill point is the deepest possible contact. Any kind of currents that |
|
| 74:52 | into this. Beyond this point, going to spill out this incline somewhere |
|
| 74:57 | the southwest here. Okay, And so we have different different controls |
|
| 75:15 | the different skill points. So on disclosure here, that's controlled by my |
|
| 75:25 | for top seal failure. And that be either from category entry pressure of |
|
| 75:30 | top seal or from mechanical fracturing of council. Mhm. And for the |
|
| 75:38 | seal, the highest capital management pressure salt followed by shale followed by |
|
| 75:45 | So salt will give me the best capacity shale. Next best insult would |
|
| 75:51 | third right? And this this false capacity will talk about it like this |
|
| 75:58 | going to be dependent on the amount shells. Okay. Alright. So |
|
| 76:13 | have an exercise here that I want I want to walk through. Hi |
|
| 76:19 | I I sent this separately as handouts . Did you did you get those |
|
| 76:28 | download those? Yes. Okay. right. All right. So take |
|
| 76:37 | minute with those. Take a few with those handouts. Um and and |
|
| 76:42 | these 1, 2, 3, questions. Um You can you can |
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| 76:48 | on the power points if you printed , you can sketch on the hard |
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| 76:52 | paper or with the power points. can sketch these different things in just |
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| 76:59 | lines in power point. Yeah. let's take Let's take 10 or 15 |
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| 77:08 | to go through this example and then then we'll go through and talk about |
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| 77:13 | together on this committee? I have question Yes, go ahead. So |
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| 94:34 | question is regarding the fault's length displacement talked about recently. So is the |
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| 94:42 | or the troll. Is it the as the sleep of the fault? |
|
| 94:49 | . Thank you. Okay, let let me have your attention and we'll |
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| 99:44 | this through together. Okay, so is the total column height? If |
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| 100:15 | of the faults seal. Okay. nothing seals then you're going to be |
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| 100:24 | this this dip closure over here on right. Okay. And the deepest |
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| 100:30 | you can go before you hit the Is 27 60 or a little |
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| 100:36 | 27 70. So that's the that's total column height. If none of |
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| 100:43 | faults sealed, it will be from crest 27 40 Down to 27 60 |
|
| 100:49 | 27 70. It's only 20 or m if none of the faults |
|
| 100:57 | Mm hmm. Questions on that 1st . Okay, the next part was |
|
| 101:24 | of a trick question. Mm What is the what is the total |
|
| 101:29 | height? If only fault see So if false see seals would follow |
|
| 101:34 | leaks. You still have the you still have the same answer. |
|
| 101:43 | still only seal down to This dip at 27 60 or 27 70 |
|
| 101:50 | So your total calm height if see seals only Is the same 20 |
|
| 101:56 | 30 m and none of the false . Now, what is the total |
|
| 102:16 | height if only false of B and . C. O. So we're |
|
| 102:20 | to seal along B in a long . Mhm. And that gets us |
|
| 102:32 | to about But 20 800 m This is the this contour 2800 |
|
| 102:42 | It's both these faults. If I deeper that spills out here, default |
|
| 102:49 | and escapes out over here. So both B and C. C. |
|
| 102:55 | . I can seal 60 m Or the crest here at 27:40 down to |
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| 103:01 | 28:00 Only about 60 m. what is the total column height? |
|
| 103:21 | false A B and C seals. if everything seals long, a long |
|
| 103:26 | in a long sea. So this all, this is all in false |
|
| 103:31 | closure. Then I can seal all way down to this Sinclair oil spill |
|
| 103:40 | here between about 29 80 and 3000 here. So that gives me a |
|
| 103:51 | column height of 27 40 Down to , 29, 90 It's about 2 |
|
| 104:01 | or 250 m. If everything I have a question yes, |
|
| 104:19 | How do you know that? The is the crest. Just by looking |
|
| 104:25 | this map. Oh well 27 40 the highest contour. You could come |
|
| 104:30 | little bit higher than that. You interpolate between 27 40 and the next |
|
| 104:38 | , which would be 27 20. you could be up to like 27 |
|
| 104:44 | mm hmm. But you're just, know, it has to be above |
|
| 104:49 | in less than the next time it's because that contour is not there. |
|
| 104:55 | you could be a little higher than but less than 27:30. Less than |
|
| 105:00 | 20. So are these subsidy These are subsidence. Yes. Got |
|
| 105:09 | . Yeah. Everything will talk you know the depths are relative to |
|
| 105:21 | level. So temporarily there will be sea level. It will get some |
|
| 105:28 | ones when we talk about rocky mountains we get closure above sea level because |
|
| 105:32 | elevation is so high. Number Anyplace else these deaths will eat below |
|
| 105:38 | level. So the bigger number of deeper. Any other questions on |
|
| 106:07 | Okay, these are these are important that will be several more exercise is |
|
| 106:14 | to this as we go through. it's it's important to understand this is |
|
| 106:21 | as possible in the course. so this is a summary of everything |
|
| 106:34 | we've gone through in this first definitions of stress and strain, |
|
| 106:39 | Other faults are organized in structural styles to the stress orientation of fault. |
|
| 106:46 | , subsidizing structures and political faults and basic fault components or nomenclature. The |
|
| 106:56 | , the hanging wall, the core the damaged bone. Um mm |
|
| 107:03 | Football and hanging wall to keep those to keep you from getting those mixed |
|
| 107:09 | . Um Those originally supposedly those go to cornish miners for if you stood |
|
| 107:16 | a phone, your foot was on football and you would hand your lamp |
|
| 107:21 | your head. On the hanging Mm hmm. So sometimes that that |
|
| 107:28 | help you remember which is the foot in which is the hanging wall |
|
| 107:34 | Follow geometric rules. They can be as ellipses with the maximum displacement in |
|
| 107:40 | middle light. The throw is a average of 10 to 10 to 10 |
|
| 107:48 | 50. It's a good approximation Length width. Good approximation is 1 - |
|
| 107:56 | . And then falter segmented horizontally and and with increasing displacement to link up |
|
| 108:02 | in the horizontal direction, in the direction. And sometimes in interpreting seismic |
|
| 108:09 | . And you see that little in section between two steeply dipping falls. |
|
| 108:14 | really is an unfolded section and an section where the false segments have not |
|
| 108:20 | up yet. All right. And with trap closure. But we want |
|
| 108:27 | identify the crest, the dips fill . Um, the topsail capacity limit |
|
| 108:37 | the false real capacity limit in the hype, which goes from the |
|
| 108:42 | So the oil water contact of the water contact. It may be less |
|
| 108:46 | the maximum possible closure that goes from crest to the ultimate gift spill |
|
| 108:56 | Okay, Alright. This book by pack and bishkek is a good reference |
|
| 109:03 | goes through all this in a lot detail. It's an expensive book, |
|
| 109:09 | it's a really good thorough description of the things that we just talked |
|
| 109:15 | Okay, okay. That was the of the first section. Okay. |
|
| 109:25 | hmm. You want to take another break or steam on ahead to the |
|
| 109:29 | section? It could break. Okay. Hey, welcome back. |
|
| 109:39 | go on with the next section. this is structural techniques. So these |
|
| 109:45 | things that will apply to maps and sections to make sure that there at |
|
| 109:52 | possible that they're not that there aren't big busts in the maps of the |
|
| 109:58 | sections. Right. Thank you um, to start, I want |
|
| 110:06 | review the things that we went Um, what's the, what |
|
| 110:11 | what is point a anybody? you didn't let me know the fourth |
|
| 110:19 | from tip. Yeah. Perfect. what is and then we've got the |
|
| 110:25 | . two lines here cut off line in a car. Fine here. |
|
| 110:31 | . The, the contours tell us this is the overthrown side and that's |
|
| 110:35 | down thrown story. So what what is this line be? Thank |
|
| 110:42 | . Because for fun, the Yeah, the football cut off. |
|
| 110:52 | what is, what is seeing I , hang on cut off. |
|
| 111:01 | Perfect. All right. And then is the what is the throw |
|
| 111:06 | D. Sure. Right there at what is the throw? Sure. |
|
| 111:34 | again please. Um, 75 sir. 3500 m here versus 34 |
|
| 111:46 | m here. So it's 75 and what's what's the throne? A trick |
|
| 111:57 | . There is no throw. There no throw zero. Right. |
|
| 112:01 | Good. Okay. Um Let's see far. Let's throw conservation idea. |
|
| 112:24 | look at is this fault fault Oh are the if you look at |
|
| 112:35 | throws here versus here along the do they add up from the throes |
|
| 112:44 | along that fault intersection? It looks they're pretty close. Yeah, they're |
|
| 113:26 | close. And here here it's about see, it's 60 100 versus 60 |
|
| 113:33 | . So it's about 100 m here . It's 60 200 versus 60 |
|
| 113:41 | So it's about 100 m here. if we go here, it's about |
|
| 113:48 | 4360-50 first news. Um We've got 50 m there. So yeah, |
|
| 114:03 | that's terrible sentence but 200 versus 100 1. 50 to 200. So |
|
| 114:09 | pretty close. Okay. These different components. What is what is what |
|
| 114:26 | a here? The food wall. football. What type of faults are |
|
| 114:36 | ? No more thoughts. Alright. is B the hunger wall hanging wall |
|
| 114:42 | the Robin? And what is 1? This one is sigma. |
|
| 114:48 | maximum stress. Perfect in three On minimal. Good. Great. Your |
|
| 114:56 | out of four. Okay. Um , I must give the answer |
|
| 115:07 | What type of faults are these? was fought. Reverse thoughts, |
|
| 115:22 | Reverse faults or thrust faults from an . The foot wall? Uh |
|
| 115:34 | One. The maximum stress. And the minimum, That's three. |
|
| 115:40 | the minimum. I gave that one . Good good job. Nice. |
|
| 115:48 | Okay. All right. So what going to look at our validating and |
|
| 115:58 | structural maps and cross sections and what gonna do is validate the maps by |
|
| 116:05 | contouring across the fault gaps. That looking at the contour differences across the |
|
| 116:11 | gaps. And then we'll validate cross by making sure they're hanging off. |
|
| 116:18 | shapes are related to the fault ships we'll make sure that the hanging wall |
|
| 116:25 | the football cutoffs match. All these are essential to make sure that you're |
|
| 116:32 | is geometrically possible. It doesn't mean perfectly right. But it has to |
|
| 116:38 | has to follow these rules at least a chance of being right. |
|
| 116:48 | All right. And the idea we're to do with the contours is that |
|
| 116:51 | we, when we contour the we typically stop the contours across the |
|
| 116:57 | . But the contours can continue across fault. Just like they do on |
|
| 117:03 | maps on a topographic map, your or surface contour comes and hits a |
|
| 117:09 | and then continues along the cliff. like showing showing here in this concert |
|
| 117:14 | , this concert come up, hit cliff and just they're still there. |
|
| 117:18 | just bunch up really tight. So going to use that concept, we're |
|
| 117:24 | apply that concept of faults. Okay Gillian. And so here I've |
|
| 117:33 | a structured contour map of the dome a fault here and I know from |
|
| 117:40 | marks and from the, the contours visits the up thrown, this is |
|
| 117:44 | down thrown side and and where that ft contour hits the fault, There |
|
| 117:51 | to be another 1600 ft contour. on the fault surface that just hasn't |
|
| 117:56 | , hasn't been drawn. So there to be a 1600-foot contour like that |
|
| 118:07 | . And if I go down the , I can draw contours like that |
|
| 118:11 | successive contour intervals. 1600 17, , 1900 and now The 1990 ft |
|
| 118:26 | intersects the down thrown side of the . So the contour comes like that |
|
| 118:31 | along the horizon and comes out the side like that. And then if |
|
| 118:38 | can continue down, I connect the contours on both sides of the fall |
|
| 118:46 | and and so on down the down hall fall. Now in my structure |
|
| 118:54 | maps, if I connect the contours the fall like that, they have |
|
| 118:59 | make some sensible pattern. There can't any crisscrossing of contours or flipping |
|
| 119:06 | I've thrown him down through the sides the fall. Okay, so here's |
|
| 119:15 | ? Yes, so like going to previous page. So in the fourth |
|
| 119:22 | , the side of the hanging the football that goes up, is |
|
| 119:27 | the downturn, downturn block or the block. So the hanging wall is |
|
| 119:35 | up front, the football is the thrown. So this is the this |
|
| 119:43 | the hanging wall. I'm sorry this the this is the football, the |
|
| 119:48 | inside and this is the hanging on down front side. Mhm. All |
|
| 120:01 | . Here's a published map from one the from an ape G bulletin |
|
| 120:05 | It's a structured contour map around the dome. You see the structure contours |
|
| 120:12 | Getting deeper this way. So this 14,014,100 14,214,314,400 here on this side again |
|
| 120:27 | contour, same con trainable 14,514,414,300. at this point what's the what's the |
|
| 120:40 | and down thrown side of the The octagon side is going to be |
|
| 120:57 | part of the higher elevation, the 500 parts. Why the downturn side |
|
| 121:03 | the salary lower innovation. Yeah. my my pointer is on the down |
|
| 121:10 | side and here this across the fault the up current side. Mhm. |
|
| 121:17 | I come over here and look at contours across here which is the up |
|
| 121:22 | side and which is the down thrown . So here I've got 14,600 on |
|
| 121:53 | side of the fault vs Something deeper 14,500 on this side of the |
|
| 122:00 | 14005 50. So 14 600 versus 5 50 which is the down thrown |
|
| 122:25 | , 14 6, 14 5 The output is the downloads right? |
|
| 122:34 | , yeah. So this is this and down is wrong. This is |
|
| 122:38 | , this is the down thrown side and this is the up front side |
|
| 122:44 | . And so there are really two faults across here. This one is |
|
| 122:51 | through it on this side, this is down throwing on mm hmm This |
|
| 122:57 | . Okay. And if I, I connect the contours across the |
|
| 123:11 | it looks like this contreras on the define a down thrown side here With |
|
| 123:19 | 1500 connecting with this 1500 15 6 14 6 connecting with that 14, |
|
| 123:28 | year. And if I go the sense of dip on fault |
|
| 123:35 | So here I've got up thrown and , thrown in. The contours connect |
|
| 123:43 | of 14,100 to 14,100, 14,200 to and so on 14 3 to 14 |
|
| 123:54 | , 14 4 14 5 defining a that's dipping to the south. So |
|
| 124:02 | I've got a normal fault dipping in south here, I've got a normal |
|
| 124:06 | dip into the north. Um and telling me that these are really two |
|
| 124:11 | faults, there, not one through fault like this. Um and so |
|
| 124:17 | can use those um use the sense throw from the contours and the contra |
|
| 124:24 | constructed on the fault to tell whether faults are geometric way possible or |
|
| 124:36 | Okay, mm hmm. Okay. here, take a few minutes, |
|
| 124:44 | along this thrust fault, eh and at the contours on the north side |
|
| 124:52 | the south side and decide what the of which side is up and which |
|
| 124:57 | is down along this fault. in this these contours, you see |
|
| 125:17 | plus. So these are actually above level. So this way I'm going |
|
| 125:22 | , this is the crest is the numbers get smaller. You're getting deeper |
|
| 125:30 | this case because they're above sea level . What? Mhm. About |
|
| 127:10 | Sorry, say again. Um uploads the downwards about the toast. Is |
|
| 127:21 | ? Yes. So on here We elevations of 800 and 900 vs elevations |
|
| 127:28 | 600 - 400. So along this is the up thrown side. |
|
| 127:35 | about what about? Over here here got elevations of Plus 900 plus Plus |
|
| 127:58 | 75, a little deeper than 900 versus um Elevations of 1000 here. |
|
| 128:07 | over here, this is up through that's down thrown, mm hmm. |
|
| 128:13 | this is mapped. There has to a mistake because the sense of thrown |
|
| 128:18 | from at this point along the fault this point along the fault. So |
|
| 128:30 | I look along here at the it's up on this side and down |
|
| 128:35 | this side. Where's that coming? when I come over here, it's |
|
| 128:40 | on this side done on this So something's wrong with this false interpretation |
|
| 128:48 | on the horizon contours. This has be two different thoughts. Maybe a |
|
| 128:54 | fault here and a thrust fault merging other way along here. So two |
|
| 129:02 | different faults. I don't know. this is another another map of a |
|
| 129:22 | thrust belt field. Look along this . Cd and um, look at |
|
| 129:33 | difference in contours across the fault, elevation above sea level. So as |
|
| 129:38 | get higher, as the numbers get , they get higher and see if |
|
| 129:43 | displacement is consistent along this fault. . The south side of the city |
|
| 130:26 | the optional side. While the north . Is it down to your side |
|
| 130:32 | to activation. Nasa has a higher than the the south side of the |
|
| 130:38 | the south side of the photos. higher division that the north side of |
|
| 130:42 | float. Yes, that's that's Mostly until you get way over |
|
| 130:50 | Now it flips again because now I've um 700 against. It's not clear |
|
| 131:00 | 600 in this in this area. seems to change here. I've got |
|
| 131:08 | Against 500. So no, maybe throw there here, you're correct. |
|
| 131:13 | going away around this is up and is down, Sorry. Okay. |
|
| 131:23 | here, just like you said, are correct. This is the up |
|
| 131:26 | side. This is the down thrown . Mm hmm. And that's clearly |
|
| 131:31 | case until you get to about here then when you get over here, |
|
| 131:36 | really aren't enough contours, I guess determine ah you may have no fault |
|
| 131:43 | just a small fault in here Because is 500 ft interval, you have |
|
| 131:49 | longer there. But along most of theory here, the fault is must |
|
| 131:56 | dipping the other direction, must be on this side and up on this |
|
| 132:13 | . Okay, so here's here's another . We've got contours on both sides |
|
| 132:18 | the fall. This is a two travel time. So as the numbers |
|
| 132:24 | bigger, you're getting deeper. So is going Went down here from 16 |
|
| 132:29 | to 16 5 to 16 6. at the sense of throw across A |
|
| 132:39 | across B. Both in the up in the upper area here and in |
|
| 132:45 | down giant area here and over here see if they're consistent again. If |
|
| 132:54 | if you can either a power point on paper copies but construct contours across |
|
| 132:59 | fault and see what that tells you the faults. There's definitely something wrong |
|
| 136:03 | the north for the top part of fault block that the contours are |
|
| 136:13 | Yeah, exactly. Right. And you have a similar problem here along |
|
| 136:18 | be fault. So um so if look at the sense of throw in |
|
| 136:29 | contours um It doesn't make any You end up with crossing contours in |
|
| 136:36 | area. If you try and connect concerts across there. If you go |
|
| 136:40 | 4 64 16 5, 2, 5, it's, it makes like |
|
| 136:49 | pinball, you have crossing contours. impossible in the sense of throat changes |
|
| 136:55 | here from, I've thrown here and , thrown here vs up thrown here |
|
| 137:01 | down, thrown here here. there's another problem phantom at this point |
|
| 137:12 | have 1640 contours potentially right across the and here again. Oh, it |
|
| 137:22 | . Maybe it flips here. It to be down to the north |
|
| 137:26 | maybe down to the south. So would have to connect the contours |
|
| 137:31 | Um, you have another crossing contours The 1660 could connect you to this |
|
| 137:38 | or this way. Right. So telling you there's potentially no fault |
|
| 137:46 | Mhm. Now there are two two solutions to this one is that the |
|
| 137:54 | are incorrect, faults are aliens are connected where the horizons are miss correlated |
|
| 138:02 | . So this is a, this a map based on seismic data, |
|
| 138:06 | from the, from the time mm hmm. If I go down |
|
| 138:13 | loop relative to here, then If this block is down a loop |
|
| 138:18 | to the surrounding blocks, then everything out just fine. Mhm. So |
|
| 138:24 | sometimes there's problem is telling me that faults are wrong and sometimes it's telling |
|
| 138:30 | that the horizons are miss correlated and know, this is a, this |
|
| 138:41 | a real map from, from producing and this was selected as an infield |
|
| 138:48 | . And because there was no, you had to make a jump correlation |
|
| 138:51 | this block. And um, somebody made the interpretation picked them on |
|
| 138:59 | If they've got a loop lower than the faults would have made sense. |
|
| 139:04 | with this interpretation it doesn't make any . But sometimes it's telling you about |
|
| 139:09 | falls and sometimes it's telling you that are correlated. Okay. Here's another |
|
| 139:25 | . This is a again, a , A real man from an infill |
|
| 139:31 | proposal. Yeah, false remount here here. And this was targeted as |
|
| 139:39 | day and field block. Mhm. these, these pencil notes in here |
|
| 139:47 | 50, 50, 50, 50 . All those pencil notes are the |
|
| 139:52 | wonderful. Right. Look at the . Look at the contours across across |
|
| 140:03 | fault. Mhm. And and see it tells you about the fall. |
|
| 140:10 | you, would you drill, would drill this target or not? You |
|
| 140:14 | have a producing well here. Could put another precinct? Well in this |
|
| 140:19 | block. Hello sir. Yes, ahead. So I will say I |
|
| 142:29 | dream in that air because I feel , oh, I believe that the |
|
| 142:37 | the creating kind of a seal for , because I see two rolls, |
|
| 142:44 | producing wells one way we have the and the other side towards the north |
|
| 142:50 | the southeast of the map. So feel like the fourth kind of creates |
|
| 142:57 | a burger towards the flow. So have a buyout where we, where |
|
| 143:03 | reservoir do not spill. Yeah. the, to where we have the |
|
| 143:09 | inside or inside the boundary of this of this fault system. Yeah, |
|
| 143:18 | . So mm hmm. You wouldn't to drill in this area. That's |
|
| 143:24 | . This what you see is that fault is um there's, there's one |
|
| 143:29 | here dipping to the north. There's fault dipping here. Another fault here |
|
| 143:35 | to the south and the throw on is consistently 50ft along here Until you |
|
| 143:43 | to this contour and it's actually 0' here. So you have a leak |
|
| 143:48 | between these two faults in this. , most likely would have trained through |
|
| 143:54 | lead point to train this block as as as this other block. |
|
| 144:01 | okay. I didn't see the second this second fault. I thought they |
|
| 144:06 | all different towards the south. I see the, so that means that |
|
| 144:10 | related to romp around there. Yeah, yeah. So so the |
|
| 144:14 | slips again. This is dipping to north. This one is dipping to |
|
| 144:17 | south and that that creates this ramp no fall, no throw in between |
|
| 144:25 | . Um and this is this is of cool because it's a highly detailed |
|
| 144:33 | where the interpreter is provided all the that you need to make an educated |
|
| 144:41 | about whether this would be an infill or not. So. Mhm. |
|
| 144:48 | a nice marriage but you still you want to drill in here because there's |
|
| 144:52 | spill point right across here. This directly to this will questions sir. |
|
| 145:05 | . Hello? Yes. Yes. ahead. Being desert. Really around |
|
| 145:11 | , doesn't it allow the there is lot to spill into the fault |
|
| 145:20 | Are we going to get a little of spill in there? See the |
|
| 145:24 | not completely but yeah it's gonna be a but it's going to be looked |
|
| 145:27 | a buffalo. Yes, it's going look like a baffle. Um The |
|
| 145:38 | reservoir in this area will have reduced and permeability and all in a couple |
|
| 145:49 | sessions. We'll talk about that in lot of detail but with with no |
|
| 145:55 | at that point the it will not a strong baffle. Okay. Any |
|
| 146:09 | questions on this one. That was excellent point about the baffling. |
|
| 146:20 | I'll go ahead probably. Yeah. this is what we explained what we |
|
| 146:30 | talked about that at this point where have zero throw in a reversal in |
|
| 146:36 | . You know the relay between here it will be a baffle. But |
|
| 146:42 | well will most likely have trained this as well. Okay, here's a |
|
| 146:55 | another similar one on structured format two travel time. So the higher numbers |
|
| 147:04 | deeper. Look at the sense of along this fault. A bee and |
|
| 147:11 | the contours across there to see what's along this fault. Abby. |
|
| 150:17 | Are you sure? Yes. So will say The south part of the |
|
| 150:24 | baby, they have this area has highest elevation. That's before this secular |
|
| 150:32 | fault. They have the higher So I will say of 2-8 Um |
|
| 150:39 | 2-300. And I would say that is up to you in part. |
|
| 150:44 | did 2 - 6? The north is a downturn part. Would you |
|
| 150:50 | by division? Um I think that's . I'm not sure exactly. Wait |
|
| 150:59 | second. But here problems Here the 50 20 to 60 is less than |
|
| 151:09 | 820 300. So it's up thrown this side down thrown on this |
|
| 151:15 | And again it gets funny. Over you get into an area where there's |
|
| 151:20 | no throw across here and it changes the throne on this side down thrown |
|
| 151:29 | this side. Mm hmm. Well in a spot in here where there's |
|
| 151:34 | no throat where you can go directly 20 to 60 to 20 to 60 |
|
| 151:39 | here. So you have a good thrown fault here and little or no |
|
| 151:46 | here. If there is a fault down thrown in the opposite direction. |
|
| 152:09 | . And what we're going to do look at a series of cross sections |
|
| 152:13 | here. First we'll look at this then this one where there's maybe no |
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| 152:18 | in this room where it's down to north. So first we'll look at |
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| 152:25 | section one. Mhm. So here section one, the yellow line is |
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| 152:33 | map level. And you see, problem here is we've actually got two |
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| 152:40 | intersecting. We've got one fault coming and another fault coming here at at |
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| 152:46 | point. This South Typical one is dominant fault and the offset is down |
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| 152:54 | the south if we go to the section. So that was this section |
|
| 153:03 | in the south. If I come section two over here, which is |
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| 153:06 | we'll look at. Next. See my there's my map arising there in |
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| 153:12 | yellow and there's there's virtually no offset this point. You're right at the |
|
| 153:18 | where these two faults intersect each they intersect each other at the horizon |
|
| 153:25 | . If I continue on to section over here. Now this phone takes |
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| 153:32 | and the sense of displacement flips now northeast side down. So again, |
|
| 153:42 | got two faults along this fault gap , I've got a south dipping fault |
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| 153:49 | here I've got a north tipping fall a little area in between where those |
|
| 153:54 | faults intersect right at the map level there's there's firstly no thrown at that |
|
| 154:04 | . Sure. So right at this , The two false intersect the intersect |
|
| 154:12 | at the map level first, essentially throw and um, this will, |
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| 154:20 | will still be a baffle on production scale on geologic time scale that will |
|
| 154:26 | see. And this is this is cool outcropping sample of that where we've |
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| 154:36 | two intersecting false one coming down this in another, coming down this way |
|
| 154:44 | in this area where the two false , you see, there's just there's |
|
| 154:50 | lot of death and destruction in there lots of minor faults. Cross cutting |
|
| 154:54 | intersecting falls. Sorry, in this it will not seal on a geologic |
|
| 155:01 | . All right. But it will a baffle on a production time |
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| 155:16 | Okay. Yeah. So next we a got a structured contour map of |
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| 155:24 | of a dome hi here, going in all four directions around it. |
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| 155:30 | contour intervals at The 50 m contour incorrect. Right? All these straight |
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| 155:37 | are blue and red. Straight lines well past and these guys are |
|
| 155:47 | Mm hmm. Here here, there another set of false here and |
|
| 155:55 | here one. And this is a is an output from from patrol using |
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| 156:04 | automated fault tracking module and patrol and it is in complicated structures. It |
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| 156:17 | a very poor job. All So if we if we do the |
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| 156:25 | exercise. If we look at the to get the offset across these |
|
| 156:32 | We identify a bunch of problems with fault interpretation. All right. |
|
| 156:38 | And this this was a cool one when I showed it, I was |
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| 156:44 | a meeting to talk about the pluses minuses of patrol. And I showed |
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| 156:51 | as a thing against the false auto in betrayal. And my manager stood |
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| 156:58 | and said I made that map And neither one of us was |
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| 157:08 | So if we look along the false here, along here, there's no |
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| 157:14 | along those faults. There's there's little no offset along this fault. And |
|
| 157:21 | if you come down to these this , single fault supposedly here and look |
|
| 157:28 | the contras, it's up front on side, down from here and then |
|
| 157:32 | flipped itself thrown here, down, here and then it flips again where |
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| 157:36 | up thrown here and down thrown here Patrol has even labeled, it's up |
|
| 157:41 | here and down from here. Um it's still, it doesn't have the |
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| 157:46 | to not identified as one fault that it all as one fault going through |
|
| 157:53 | . Um So when you're using a auto picker like in betrayal. So |
|
| 157:59 | need to pee, particularly careful to the results to make sure that they're |
|
| 158:05 | reasonable. Okay. Um All This is this is another tricky |
|
| 158:21 | We're looking at a pop up block a in a thrust terrain. So |
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| 158:28 | my crest is here, it's plunging this way and plunging off this way |
|
| 158:33 | here I've got just last week I have one fault on the north |
|
| 158:44 | , living in the south here, got one fault on the south side |
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| 158:50 | to the north connect connect the contours these two fault gaps and see what |
|
| 158:59 | tells you about the, about the . Mm hmm. If the contours |
|
| 161:18 | everything is right, it looks kind like a strain ellipse. What do |
|
| 161:30 | mean? I guess it's like the thing is just kind of extending. |
|
| 161:41 | . Mhm. You get some really stuff if you connect the contours. |
|
| 161:48 | hmm. If you just connect the from the horizon, you get contours |
|
| 161:56 | this and similarly on the north which would indicate fault dips in the |
|
| 162:02 | direction. It would indicate a self here in the north dipping fault |
|
| 162:09 | All right. But we know from seismic and the general geology that the |
|
| 162:13 | or reverse faults. So they have go the other way. If you |
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| 162:23 | and make a false dip the other , you get this kind of elliptical |
|
| 162:27 | , which I think is what Angela referring to. Um, we're now |
|
| 162:32 | are getting keeper of the south and of the north. Um, but |
|
| 162:38 | a very, it's a very strange for a fault on twitter. |
|
| 162:52 | in much, what's happening here is with this with this vertical seismic profile |
|
| 163:02 | a false something like this. where this area everything goes vertical and so |
|
| 163:11 | lose, you lose seismic, you seismic reflections. One in what's now |
|
| 163:19 | the structure contra matt or the cut points like along here where part of |
|
| 163:25 | is on the horizon and then you lose it. And there's no data |
|
| 163:31 | where the legs go vertical. Um so this that the concerts here really |
|
| 163:38 | represent the fault. They in they probably represent the verticality of this |
|
| 163:44 | plan where the fold goes vertical. you can you can apply the same |
|
| 163:54 | of connecting the contours to reverse But it's probably with seismic data, |
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| 164:01 | probably not telling you about the fault probably telling you about the vertical |
|
| 164:07 | That's in that no data zone. map is a cut off line here |
|
| 164:13 | maps the limit of seismic resolution rather an actual fault cut off. Question |
|
| 164:23 | . Yes. So in a real situation, it's the do Control the |
|
| 164:31 | control that is fully the deep of 40. That correct compared to |
|
| 164:37 | Is that more correct compared to what have right now. So this this |
|
| 164:42 | more correct from this contoured pattern is right, geometrically possible. But geologically |
|
| 164:53 | faults are never shaped like that. contours on the thrust faults should go |
|
| 164:58 | other direction. I mean, we about this a lot more further, |
|
| 165:04 | the contours on thrust faults follow something the bow and arrow rule, whether |
|
| 165:11 | go the opposite way there, um convex in the direction of thrusting. |
|
| 165:19 | there should be contoured, curved in opposite direction to what we see |
|
| 165:35 | Is that is that clear? sir, correct. All right. |
|
| 165:48 | is this is another call and this an artifact of the, the things |
|
| 165:54 | we can do with our size of packages. So we're looking at overall |
|
| 165:59 | but a faulted dome um high up with the bright colors dipping off this |
|
| 166:06 | dipping off this way. But while contact shown here in red on this |
|
| 166:11 | , um here in red on the thrown side, a series of faults |
|
| 166:18 | through here. These all these black represent false horizons and intersection lines. |
|
| 166:26 | these are where the fault picks intersect horizon. And then when you look |
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| 166:33 | at the map, you see there all these little bull's eyes along Different |
|
| 166:40 | on the map. There's one, another, there's another. Um and |
|
| 166:52 | so you have overall a dome with little like pimples or pinnacles pumping up |
|
| 166:59 | of the overall dome structure. And what's happened here is, is |
|
| 167:07 | here, let me go back this section goes through one of those little |
|
| 167:13 | . So we're looking at a cross through here that goes through this little |
|
| 167:18 | here. So there's there's my map , wow. And here's where I |
|
| 167:27 | this little pinnacle coming up or the . Mm hmm And what, what |
|
| 167:34 | interpreter is done here is take this level and he's he's trying to snap |
|
| 167:41 | to the well tops in the world and all right, some something step |
|
| 167:51 | that point. Um Either this was interview didn't use a wide enough smoothing |
|
| 167:59 | when he did the snapping of the tops or he's actually mapped the wrong |
|
| 168:04 | along here. If I pick on horizon, it's a loop higher. |
|
| 168:09 | would still follow the same structure and all the well talks. Mm |
|
| 168:15 | So when you, when you snap rise into the wells and you get |
|
| 168:19 | bull's eyes is telling you that the map interest and really doesn't represent the |
|
| 168:26 | tops and you need to, you to take the horizon loop higher to |
|
| 168:35 | all the well tops. Mhm. . Any comments or questions on that |
|
| 168:48 | before we go on. Um Yes . So I know when you're using |
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| 168:57 | to make maps, especially when the didn't either para spacing or pharaoh controls |
|
| 169:06 | equal spacing controls. You can see bull's eyes like which will refer to |
|
| 169:13 | an artifact. So can those can control method be attributed to why we |
|
| 169:19 | this broadside here or is it just ? Mhm. It it can |
|
| 169:29 | it can be either. Um And you see these bull's eyes, you |
|
| 169:36 | to go back to the original interpretation see if there ah see whether they're |
|
| 169:46 | to picking the wrong map level or they're an artifact of the snapping routine |
|
| 169:51 | you used. If you for I'm fine. If I went back |
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| 169:59 | this and kept this horizon but whitened snapping parameters. So I didn't get |
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| 170:06 | little pinnacle, I would still crosscut seismic data some distance away from each |
|
| 170:12 | of these things so that um that honoring the seismic data would tell me |
|
| 170:20 | I picked the wrong horizon here. . If you if you she snapped |
|
| 170:27 | whole event loop higher and it would through and it would honor both your |
|
| 170:33 | data and you're and you're well So you need to go back to |
|
| 170:39 | interpretation and see what the best fix , what the best correction is. |
|
| 171:01 | right. The other thing that's, incredibly important to massage the data is |
|
| 171:06 | use the time slices. Um So we're looking at a a time slice |
|
| 171:13 | you see all these beautifully image false the time slice. And then all |
|
| 171:19 | things with the yellows and the Our fault picks that have been |
|
| 171:25 | And the diamond shows where they intersect time spice. The blue shows where |
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| 171:31 | go below the time slice. The part shows where they go above the |
|
| 171:35 | slice two here in here and along of these faults. I have some |
|
| 171:44 | nice fall picks honoring the time slice . There's another really clear nice room |
|
| 171:50 | through there. Mm hmm. But these these red dashed polygons represent the |
|
| 172:04 | gaps from the horizon. And what show is that on the horizon map |
|
| 172:11 | fault picks have been alias and don't the actual fault. So this fault |
|
| 172:19 | for example is combining part of this with part of this fault. Oh |
|
| 172:26 | , somebody went back and the default in more detail ensure that these are |
|
| 172:33 | separate faults and not one fault going like this. This aliasing of fault |
|
| 172:41 | , happens when you make very widely fault picks and then make them |
|
| 172:47 | Um And that's why it's it's extremely to use your time slices when you're |
|
| 172:55 | your fault picks. To help get fault correlations comparably mapped. Mm |
|
| 173:02 | And again, a lot of time lapped just from the vertical profiles and |
|
| 173:06 | don't even construct the time slice But you know, if you're dealing |
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| 173:12 | a complex series of faults, it's to use that time slice data and |
|
| 173:17 | enables you to make the interpretation much instead of going through line by line |
|
| 173:24 | line, you can make one fault here and then make another one somewhere |
|
| 173:29 | here. Mhm. Make it pick the time slice itself that links those |
|
| 173:35 | space fault checks. And the result you get a better interpretation faster by |
|
| 173:42 | on the time slices as well as the verdict profiles. If any of |
|
| 173:54 | worked with time slice data and made picks like this. Um Yes |
|
| 174:01 | Um use petrol to do this time . It's it's that's an excellent thing |
|
| 174:11 | do is very very good and lets make a better interpretation faster. |
|
| 174:21 | Okay. We've been talking about maps I'm going to switch now and talk |
|
| 174:26 | cross sections and fold fold relationships and sections. And the main point I |
|
| 174:34 | to make is that hanging well fold and the underlying fault shapes are dependent |
|
| 174:40 | each other. So if you know fault shape or you know the hanging |
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| 174:45 | full shape. Um it helps you the one that you don't know as |
|
| 174:51 | . So where I have a realistic felt like this um I'm necessarily going |
|
| 174:57 | get a little roll over an incline the hanging wall collapses into the gap |
|
| 175:04 | by movement along that fall. One an anti Listrik following that like |
|
| 175:12 | I'm going to get the opposite sense folding of rotation. Um Get this |
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| 175:17 | of reverse drag into the fall as hanging wall tries to move over that |
|
| 175:23 | dip of the form similarly from reverse where I have a Listrik shaped reversible |
|
| 175:30 | this. And so I moved this from right to left across here. |
|
| 175:36 | going to push it up that district and create a hanging wall to climb |
|
| 175:40 | in here, right. If the , it's the fault tips out, |
|
| 175:48 | get a nice symmetric an incline that a full bend fall over the |
|
| 175:54 | It's again related to the shape of fall where the fault is horizontal. |
|
| 175:59 | no vertical displacement of the beds. only where the false starts to ramp |
|
| 176:05 | . That you start to get the of the overlying beds. So when |
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| 176:09 | here, the fault is flat. horizons are not displaced vertically. It's |
|
| 176:15 | when they start to go up the . So you start to get this |
|
| 176:18 | up the of the hanging wall And these are the for normal |
|
| 176:28 | these are the three basic fault geometries you have a plane or fault, |
|
| 176:34 | just have planter beds and no rotation the beds. Where you have a |
|
| 176:39 | shaped fall like this. You have roll over an incline collapsing into the |
|
| 176:44 | phone where you have this anti Listrik shaped like this. Then you get |
|
| 176:50 | reverse drag up into the up into falls here. Okay, excuse |
|
| 177:07 | So this this gets a little more with growth faults and growth fault geometries |
|
| 177:15 | um as the extension occurs, the increases from the shallow levels down to |
|
| 177:24 | deep level. So here where the is tipping out, you have little |
|
| 177:29 | no displacement. The moderate displacement here the light cream in a large displacement |
|
| 177:35 | the green and the purple here and football in the green and the purple |
|
| 177:40 | and the hanging wall. Um When restore these, wow, you only |
|
| 177:50 | get a little bit of displaced. even work here. Mhm. And |
|
| 177:55 | you restored deeper and deeper horizons, get more and more of the displacement |
|
| 178:02 | with the reconstruction or with the Right? So this is an animation |
|
| 178:12 | a Listrik normal fault. Mr over see is that is the hanging wall |
|
| 178:24 | out to the right. This part the hanging wall collapses into ballistic normal |
|
| 178:31 | here. From this point outwards, no vertical displacement of these hanging wall |
|
| 178:39 | . But from this point in board get this roll over an incline. |
|
| 178:57 | was this animation is just a nice to show how the hanging wall shape |
|
| 179:01 | the full shape are related. now, when we when we get |
|
| 179:16 | roll over anne klein, we've got very complex series of false developed in |
|
| 179:23 | . Okay, and this is an where here's my Listrik Master fault going |
|
| 179:31 | here, but here's my hanging on . And as these beds roll over |
|
| 179:38 | that Listrik Normal farm, I get series of conjugate normal faults. |
|
| 179:44 | to hear that allowed this extension and over of the annual as the fall |
|
| 179:52 | out um I get more and more these false generated higher in the |
|
| 179:59 | So I get multiple generations of these where here I've got the first set |
|
| 180:04 | this moves over the inflection point. , as I continue to move out |
|
| 180:08 | the inflection point again, another series faults here at G two. And |
|
| 180:14 | continued movement over that extent inflection point successive generations of G three and G |
|
| 180:22 | formed as the hanging wall moves over inflection point in the listed fault. |
|
| 180:30 | , as a result of this list geometry, I end up with a |
|
| 180:33 | complex set of conjugate normal faults. used to hang along. All |
|
| 180:44 | so here's an animation of a complex fault where we have concave up |
|
| 180:51 | Concave down anti Listrik shape and then Listrik shape again. And you see |
|
| 180:57 | to hang all beds change depending on part of fold their passing over here |
|
| 181:04 | the district part of the default I get a garden variety role of |
|
| 181:09 | klein here over this anti Listrik I get this reverse track over this |
|
| 181:18 | , creating an overall and declining Doing this again. Okay, so |
|
| 181:47 | see here we get the rollover and clone here we get the reverse track |
|
| 181:52 | this concave up part of the fault where it goes, Listrik again, |
|
| 181:58 | get it roll over anne klein Internet part of the fault. Oftentimes |
|
| 182:05 | seismic data, this part of the verily poorly imaged in this. The |
|
| 182:13 | of the hanging wall built is well . And so you can use that |
|
| 182:18 | while geometry to infer what the fault needs to be. Mr um you're |
|
| 182:31 | to use an example of that from mhm sandbox model. Friend ballistic |
|
| 182:38 | The animalistic shape, realistic shape. here in the update district shape. |
|
| 182:44 | see that that role over an incline with the anti Listrik part. You |
|
| 182:50 | that reverse track in the crust of rollover. You get these extension all |
|
| 182:56 | allowing the beds to extend into that of around a climb. And here |
|
| 183:03 | you go from this, this Listrik to a flat. You got another |
|
| 183:09 | of constant normal flashing allowing the best extend and roll over to create |
|
| 183:16 | Mm hmm. To create this mystery shape. So here's, here's an |
|
| 183:32 | from seismic data. Um so there's , my master fault going through here |
|
| 183:40 | . I've got a Listrik concave up and then sort of a flat, |
|
| 183:45 | concave up shaped concave up shape through . Ah And so as this extends |
|
| 183:52 | the right, I get a roll an incline here with complex series of |
|
| 183:59 | normal faults and the crest of that of randy klein. Mhm. Older |
|
| 184:05 | out here, younger ones forming closer to the inflection point in these |
|
| 184:12 | move out to the right and then I go over this inflection, I |
|
| 184:18 | a synthetic normal fault here that takes the strain associated with going over that |
|
| 184:25 | point. And then here everything is plainer. And so the guys are |
|
| 184:30 | down dropped along, not playing or with minor countries faulting along the |
|
| 184:44 | Alright, this this is an example these crystal collapsed ground faults from producing |
|
| 184:52 | in Nigeria. All these steeply dipping services represent individual faults. Mm |
|
| 185:01 | The lightly colored surfaces here and here the purple and here in the yellow |
|
| 185:07 | different reservoir beds. And you see these contribute faults come down and they |
|
| 185:15 | each other. Um And you end with very complex shaped fault blocks. |
|
| 185:21 | the part of the importance of this as you go deeper, if folk |
|
| 185:26 | gets smaller and the trainable volume of folk blocks gets smaller and smaller. |
|
| 185:32 | the well planned, it gets more more complicated as you go deeper and |
|
| 185:36 | into this complex. Mhm. What we're seeing here on kilometer field |
|
| 185:50 | is the same as what we saw that seismic data with these cross cutting |
|
| 185:56 | falls and analogous to what we saw our crop here, where we have |
|
| 186:01 | cross cutting normal falls and we have lot of death and destruction intersecting faults |
|
| 186:07 | writing those conjugate zones. Mhm. so these. Mhm. Well planning |
|
| 186:15 | complicated. The reservoir blocks get smaller the baffling between default blocks becomes |
|
| 186:23 | very strong. Okay, so these faults where X falls involved from the |
|
| 186:40 | of different faults. Children's like we about earlier. So here I've got |
|
| 186:45 | two normal faults dipping in opposite It's just a schematic. So here |
|
| 186:52 | see from the contours dipping to the here we're dipping to the south. |
|
| 186:59 | as these faults grow, they're going intersect each other, inform this. |
|
| 187:07 | content. Excuse me. This conjugate along a cross section by a prime |
|
| 187:16 | . And we'll see this geometry where a while the green fault dominating, |
|
| 187:22 | the red fall as we progress That will change. Okay, as |
|
| 187:32 | progress alarm that will change until the fault becomes the through going fault in |
|
| 187:36 | green fault is offset by the red . That's all um an artifact or |
|
| 187:46 | of how these faults grow from different with opposite opposing dips. Mhm. |
|
| 187:56 | . Now this is another, this another example. We've gotta Listrik fault |
|
| 188:02 | with a rollover and inclined here With main conjugate here. f. one |
|
| 188:08 | lots of minor anesthetic and synthetic faults here in the yellow. And this |
|
| 188:16 | this Robin block A. Is a infill target. Mhm. And here |
|
| 188:25 | the In the hanging on the football 4. 1 of these three horizons |
|
| 188:31 | . B. And C. But the other side in the gravel in |
|
| 188:38 | . Um I have only interpreted one a. And this is um this |
|
| 188:53 | this is showing me an error in interpretation If I have something like A |
|
| 188:59 | and C. On one side of phone, I have to have those |
|
| 189:03 | things on the other side of the and these things can't just disappear completely |
|
| 189:08 | this section. And so the mismatch here means that the city horizon in |
|
| 189:14 | grabbing has to be pulled up higher fit these BNC horizons in the in |
|
| 189:21 | grab in here. And so the lesson to take away from this is |
|
| 189:28 | that hits one side of the fault to be present on the other side |
|
| 189:32 | the fault right? And for an target like this it gives you more |
|
| 189:39 | , it gives you three target horizons of just one. So the fact |
|
| 189:45 | you have a BNC on this sort thought, I mean you have to |
|
| 189:48 | a B and C in the grabbing on this side of the phone, |
|
| 189:54 | you have a question. So this a restrict normal for the abc in |
|
| 190:01 | hanging wall of the great forts. one should go down. Well I'm |
|
| 190:08 | since um section A has been Section B and C. Might be |
|
| 190:14 | by this vote at this popular forts deep in the opposite direction. So |
|
| 190:21 | taking you that it's a reason why represented in there. Um No because |
|
| 190:31 | as long as as long as they the green fault here, they have |
|
| 190:36 | be on the other side of the fault. They can't be faulted out |
|
| 190:56 | . And one of the things that can do to evaluate this further, |
|
| 191:01 | see if I have any need. rather than just picking on tracks and |
|
| 191:12 | , you can take an arbitrary line goes from here around that goes into |
|
| 191:19 | in the place of this section, dip around the tip of F. |
|
| 191:24 | for and then comes back up into grub and here and carry these three |
|
| 191:32 | around the tip of the fault back the ground in this way. And |
|
| 191:37 | that's the best way to confirm where are in the grab in here. |
|
| 191:43 | alternative thing you could do would be try and do a reconstruction this |
|
| 191:51 | And if you restore it to this . Level here and here we will |
|
| 191:56 | a gap in this in the keel the grab in here. Or that's |
|
| 192:02 | you you have to have B. C filling in here and the |
|
| 192:05 | Has to be higher in the in grabbing block here. Right? So |
|
| 192:11 | are two ways you can check this is using An arbitrary seismic line that |
|
| 192:17 | all the way around fault. the other more complicated way is to |
|
| 192:21 | a reconstruction mm hmm. To see happens when you restore the A. |
|
| 192:26 | a horizontal datum. But either way will get you to the same. |
|
| 192:33 | answer point telling you that you need have B. And C. In |
|
| 192:36 | ground here. If it hits one of the fault, it needs to |
|
| 192:40 | on the other side of the Mm hmm. Okay. Here's |
|
| 192:53 | here's another interesting one. Cross Seismic section. Crystal collapsed structure over |
|
| 192:58 | tone. Mm hmm. Reservoir horizons here and here. False sticks here |
|
| 193:08 | , here and here. Here. got a very large displacement shall in |
|
| 193:16 | section and basically no displacement deeper in section. Mhm. What does |
|
| 193:25 | what does that tell you about about the faults or about the default |
|
| 193:31 | system here? The reason why we no displacements in the blue and |
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| 193:41 | is that area is the tip of fault before too. Um that's that's |
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| 193:51 | good answer. That's one possible I mean, one possible answer. |
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| 193:56 | . Mhm. Mhm. The other , if you mm hmm. If |
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| 194:21 | flatten on the green horizon or you on the green horizon here, you're |
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| 194:26 | to pull these guys up into a sense of offset across fear implying that |
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| 194:33 | would be a reactivated originally reverse Mm hmm. And depending on, |
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| 194:42 | your tectonic setting, you can probably that or not. Um The |
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| 194:49 | the other possibility is just that these been the seismic data is not so |
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| 194:58 | in here and these have been smoothed cross it. Mm hmm. So |
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| 195:04 | than having before tip out here, you could drop these horizons down to |
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| 195:13 | a consistent displacement across default. So would be displaced from here to there |
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| 195:22 | from there to down here somewhere. trying to think how you could tell |
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| 195:38 | this were oh, the fault tip not. Mm hmm. I don't |
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| 195:52 | how you could. Mm hmm. you can check that interpretation for |
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| 195:58 | I think there might be a possibility you would just have to live |
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| 196:03 | You might not resolve that to those possible interpretations. Yes. Okay. |
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| 196:18 | right. So, um, let's . Let's see how much is left |
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| 196:25 | here. Yeah, there's not there's too much left in this section. |
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| 196:33 | let's go ahead. Sure. The important thing in cross sections is making |
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| 196:44 | that you're flats and rams match. , here we've got a Listrik. |
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| 196:50 | fault with the rollover and decline. hmm. And this is a where |
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| 196:59 | , where the beds make a high or cut off is considered a rant |
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| 197:04 | the beds make a line or cut . Like this is considered a |
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| 197:09 | Mhm. In the ramps and the I need to match in any |
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| 197:15 | So here, I've got randy with corresponding ramp here here, I've got |
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| 197:21 | flat with no corresponding flat here in football here, I've got another ramp |
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| 197:28 | a corresponding ramp here in the yellow the football. If I try and |
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| 197:33 | this. If I flatten on the horizon, I create a gap in |
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| 197:40 | at the base of the at the of the green horizon. So, |
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| 197:46 | this was telling me that the fault in here has to change. Also |
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| 197:53 | this rollover track here is telling me the fault needs to have an anti |
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| 197:58 | shape deeper here in the session. hanging wrong interpretation is telling me that |
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| 198:06 | fault interpretation, it has to change this Listrik shape to a Listrik shape |
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| 198:12 | an anti Listrik shape deeper here in section. So here's the here's the |
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| 198:23 | interpretation where I have Listrik falls upper the upper part and an anti Listrik |
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| 198:30 | deeper here in the lower part. . This is consistent with the, |
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| 198:35 | the cut offs. Now I just hang high and will cut off on |
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| 198:40 | sides. 24. I've eliminated the in this flat ground interpretation. |
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| 198:49 | And if I was prospecting for target down here, lower in the section |
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| 198:54 | hands. Um I have a trap I don't have in in in this |
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| 199:09 | . So again, two things the ramps and flats have to match |
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| 199:14 | the shape of the with the hang fold has to match with the shape |
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| 199:19 | the underlying fold. So both of are telling you, you have to |
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| 199:23 | this this drunken antes restrict termination fault now in thrust faults, thrust fault |
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| 199:37 | . Um It's very important to get ramps and flags to match again and |
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| 199:43 | is a cartoon showing how that So here's the on the farm state |
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| 199:50 | the full while here and hanging out , I have a ramp here in |
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| 199:57 | foot long and a corresponding ramp here the hanging role. Then I have |
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| 200:02 | flat here in the football with a flat and the hang on another ramp |
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| 200:09 | in the football with a ramp in hanging long and finally the last flat |
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| 200:15 | in the football. And so in deformed state, if I move this |
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| 200:23 | right to left, end up with shape in the hanging wall. But |
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| 200:28 | still have the same ramp flat This ramp and hanging along is now |
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| 200:36 | ramp here in the hanging wall street state. This flat is this flat |
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| 200:43 | the base of the blue. This cut off in the green, is |
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| 200:48 | ram cut off from the green and this flat and the base of the |
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| 200:53 | . Is this flat in the base the korean here. And so mm |
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| 201:00 | . When we're looking at an informed interpretation like this, you want to |
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| 201:04 | through the football and hanging on and sure that you have the same matching |
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| 201:11 | and flats in both the football and hanging off. Alright, so this |
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| 201:23 | an alternative interpretation. So I have similar hanging wall geometry but my ramps |
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| 201:29 | flats don't match Here. I've got one ramp in the football and then |
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| 201:36 | long flat in the base of the and the hanging wall. Whereas in |
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| 201:42 | football I have two ramps, one . He had to get the cut |
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| 201:47 | of the blue and then went back at the cut off of the |
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| 201:51 | So in this case the ramps and don't match and I don't get to |
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| 201:56 | a bull session in here. If try and restore this to match the |
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| 202:01 | cutoffs and up the gap here, telling me I have to go back |
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| 202:06 | revise the interpretation. Alright, come here. So here thrust fault, |
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| 202:24 | sections on. We want to make that the ramps and the flat |
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| 202:30 | Um But then there are these additional . The bed thicknesses and lengths need |
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| 202:36 | be constant in the a deformed state the under formed state. The flats |
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| 202:41 | to be located in the shells. ramps need to be located in massive |
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| 202:47 | stones or massive carbonates. The number ramps in the hangar all need to |
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| 202:52 | the number of ramps in the football similarly, the number of number of |
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| 202:57 | of flats in the hanging wall. too, for the rights a number |
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| 203:02 | flats in the football stream. so this is this is a summary |
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| 203:23 | what we just talked about that these of flats need to match. |
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| 203:28 | Mm hmm with geo mechanical restorations. way those work is that they strain |
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| 203:36 | elements to make them fit back It's like it's kind of like putting |
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| 203:40 | jigsaw puzzle together with a sledgehammer. here's an example of that. Where |
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| 203:47 | I have an unbalanced herbal section. see, I have one ramp here |
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| 203:52 | then a long flat. It's the of the purple. And in the |
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| 203:57 | I have one ramp here and then ramp here at the purple cut |
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| 204:02 | Mm. When I restore this with two mechanical restoration, I can strain |
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| 204:08 | hang around football to make these things back together in doing that. You |
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| 204:15 | , I get these distortions and thicknesses the beds. I have a lot |
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| 204:19 | thickening um warm along the mismatch of thrust fault. And these will show |
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| 204:28 | in your geo mechanical restorations as high areas. And you need to go |
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| 204:33 | look at the thickness is and and if the thicknesses are constant or |
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| 204:38 | If the thickness isn't enough. If thicknesses are not constant, it's telling |
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| 204:42 | that there's there's an error in the . And even even though it's restored |
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| 204:47 | mechanically, but it's not, it's a geologically reasonable answer. All |
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| 204:56 | And Danelle is sort of the leading restoration package. And if you when |
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| 205:04 | use that, you need to be careful to make sure when you do |
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| 205:08 | restoration, you don't get these crazy and that you've done thicknesses remained |
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| 205:20 | Okay, so to summarize this section Matthew criteria, the false must have |
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| 205:28 | sense of offset to the sense of and down thrown sides has to be |
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| 205:34 | along the fault. The contours across fault gaps needed to find consistent |
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| 205:41 | If you get flips in the deeper contours, it's telling you that you've |
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| 205:46 | correlated the frogs and you need to extra careful to QC auto pitfalls and |
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| 205:54 | auto picture horizons or snap horizons. hmm. Look out for those bull's |
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| 206:00 | that were identified to make sure that have the right horizon and use the |
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| 206:05 | smoothing parameters in cross sections. the hanging draw shapes and football shapes |
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| 206:14 | to need to correlate. So if have a plane or fault, I |
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| 206:18 | to have plane of horizons. if I have planted horizons, they |
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| 206:23 | to have a plane or fault. I have a rollover anna klein, |
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| 206:28 | need to have a Listrik fault. conversely where I have a Listrik |
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| 206:32 | I have to have a room of klein where I have a concave up |
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| 206:38 | anti district fault. I need to this reverse fault track into the |
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| 206:43 | Or conversely, if I see this track, I need to have this |
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| 206:47 | mistress shaped in the fall. And then lastly, hang on. |
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| 206:54 | cutoffs need to match and both our faults and then reverse faults and the |
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| 207:00 | and flats in the number of faults reverse faults. The color match. |
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| 207:10 | . So that's, um, that's I'll wrap up for today. We'll |
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| 207:15 | tomorrow again. It'll all be virtual we'll start talking about it to your |
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| 207:20 | at 8 30. Tomorrow morning. the whole course going to be virtual |
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| 207:26 | just this weekend? You know, whole course is going to be |
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| 207:29 | Yes. Okay. You know the you used today that will work for |
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| 207:36 | friday and the link that you got tomorrow will work for every saturday carry |
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| 207:51 | . Okay. Anymore. The So it's the Internet and the final |
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| 207:55 | be on the line. I'm I didn't hear that. The, |
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| 208:05 | , the mentor and the final will online as well. Thank |
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