J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4Due:Due: Tuesday May 12, 5:00 PM in my office LME 217. Tuesday May 12, 5:00 PM in my office LME 217.This quiz will take you briefly through all the steps ofThis quiz will take you briefly through all the steps of a complete interpretation ofa complete interpretation of

the F3 data set you have on your hard drives. It is of course abbreviated tothe F3 data set you have on your hard drives. It is of course abbreviated toallow you to complete the interpretation elements in a few hours (I hope)allow you to complete the interpretation elements in a few hours (I hope)instead ofinstead of a few weeks. As with all interpretations, there is never one a few weeks. As with all interpretations, there is never one ““rightright””answer. I will give the most credit for theanswer. I will give the most credit for the most cogent arguments for yourmost cogent arguments for youranswers.answers.

Complete this quiz on your own, without talking aboutComplete this quiz on your own, without talking about it with anyone else exceptit with anyone else exceptme or Prof. me or Prof. TrexlerTrexler. I invite you to talk to us as you work on the quiz. You are. I invite you to talk to us as you work on the quiz. You arealso welcome to look in the library and on the internet for prior interpretationsalso welcome to look in the library and on the internet for prior interpretationsof this data set, but none of that should be necessary to complete this quiz.of this data set, but none of that should be necessary to complete this quiz.

I recommend you watch the I recommend you watch the Basic InteractionBasic Interaction video under Tutorials at video under Tutorials atOpendtectOpendtect.org if you have not already. The v3.2 .org if you have not already. The v3.2 New Features New Features video explainsvideo explainsfault picking.fault picking.

If you have trouble accessing the F3 data setIf you have trouble accessing the F3 data set with with OpendTect OpendTect in the in the DataWorksDataWorksLab, or with your own PC, I will arrange access to another appropriate facility.Lab, or with your own PC, I will arrange access to another appropriate facility.

Each questionEach question here gives you the section coordinates where I was able to seehere gives you the section coordinates where I was able to see aafeature of the type I ask about, and shows my picks of that.feature of the type I ask about, and shows my picks of that.

J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4In addition to providingIn addition to providing answers to questions,answers to questions, and discussingand discussing how you make yourhow you make your

interpretation, I will want to interpretation, I will want to seesee your interpretations. You can your interpretations. You can show me what youshow me what you areareinterpreting ininterpreting in one ofone of 3 different ways. Use the method that you find easiest for any3 different ways. Use the method that you find easiest for anyparticular question:particular question:

Zoom in on a horizontal or vertical sectionZoom in on a horizontal or vertical section that shows what you are interpreting, andthat shows what you are interpreting, andsnap a JPEG picture of it with snap a JPEG picture of it with OpendTectOpendTect’’s s CameraCamera button. Tell me the location of the button. Tell me the location of thesection you are looking at, and draw the interpretation I ask for on the picture. You cansection you are looking at, and draw the interpretation I ask for on the picture. You candraw in MS-Word afterdraw in MS-Word after bringing the picture into there, orbringing the picture into there, or you can print the picture inyou can print the picture incolor or black and white and draw on it with a pencil.color or black and white and draw on it with a pencil.

Make picks onMake picks on horizontal or vertical sections using horizontal or vertical sections using OpendTectOpendTect’’s s PicksetPickset function. Forfunction. Foreach interpretive element, start a new 2d or 3d polygon each interpretive element, start a new 2d or 3d polygon pickset pickset inin a different color, anda different color, andwith a name describing what you are picking. When you have finishedwith a name describing what you are picking. When you have finished making the picksmaking the picks(1 to 20 or so), save the (1 to 20 or so), save the picksetpickset, and then Export it to a text file (with , and then Export it to a text file (with X/Y/t coordsX/Y/t coords, not, notInline/XlineInline/Xline) with a) with a name describing what it is. Email the text files to me, and I can thenname describing what it is. Email the text files to me, and I can thenimport them into import them into OpendTect OpendTect and see your interpretation. I recommend this method forand see your interpretation. I recommend this method forturning in all your interpretation elements.turning in all your interpretation elements.

Some of the interpretations I ask for, likeSome of the interpretations I ask for, like a fault or tracked horizon, have their owna fault or tracked horizon, have their ownfunction and data type in function and data type in OpendtectOpendtect. If you make your interpretation in one of these. If you make your interpretation in one of thesetools,tools, Save the element (they donSave the element (they don’’t get saved when you Save your Session, but yout get saved when you Save your Session, but youwant to do that too), and thenwant to do that too), and then Export it to a text file (with Export it to a text file (with X/Y/t coordsX/Y/t coords, not , not Inline/XlineInline/Xline))with awith a name describing what it is. Email the text files to me, and I can then import themname describing what it is. Email the text files to me, and I can then import theminto into OpendTect OpendTect and see your interpretation.and see your interpretation.

J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4 Task 1: Describe the polarity and phase of the F3Task 1: Describe the polarity and phase of the F3

datadata set.set. Within the data set are appropriate places forWithin the data set are appropriate places for

determining the polarity and phase of the seismicdetermining the polarity and phase of the seismictraces. Examinetraces. Examine 2-3 of these, and describe what phase2-3 of these, and describe what phaseand polarity (and what colors) will be associated with aand polarity (and what colors) will be associated with asimple, strong increase in acoustic impedancesimple, strong increase in acoustic impedance withwithdepth. (Inline section at 472 shown.)depth. (Inline section at 472 shown.)

J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4 Task 2: Pick a fault.Task 2: Pick a fault.

The F3 dataset is rich in faults. Pick one fault and show your picksThe F3 dataset is rich in faults. Pick one fault and show your pickson at least two sections, horizontal, vertical, or both.on at least two sections, horizontal, vertical, or both.

Describe how you verified the fault by looking at both horizontalDescribe how you verified the fault by looking at both horizontaland vertical sections. (Horizontal sections at 532 and 1000 msand vertical sections. (Horizontal sections at 532 and 1000 msshown.)shown.)

J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4 Task 3: Pick and identify terminations, and trace a seismicTask 3: Pick and identify terminations, and trace a seismic

sequence in one vertical section.sequence in one vertical section. Most F3 inline sections show easily identifiable seismicMost F3 inline sections show easily identifiable seismic

sequences. Find and pick enough sequences. Find and pick enough onlap onlap and and downlapdownlapterminations to identify a lower sequence boundary, and also pickterminations to identify a lower sequence boundary, and also pickupper-sequence-boundary terminations, upper-sequence-boundary terminations, toplap toplap or truncation.or truncation.

Look at this sequence over a range of sections and discussLook at this sequence over a range of sections and discusswhether you can identify any whether you can identify any erosional erosional truncation.truncation.

Discuss how sea level changed before, during, and after theDiscuss how sea level changed before, during, and after thedeposition of your identified sequence. (Inline 471 shown.)deposition of your identified sequence. (Inline 471 shown.)

J. Louie,J. Louie, Geol 755Geol 755 Spring 2009Spring 2009

Geophysics Quiz 4 Task 4: Find something that could be a reservoir.Task 4: Find something that could be a reservoir.

F3 includes several bright spots that may be reservoirs. In oneF3 includes several bright spots that may be reservoirs. In onevertical section pick the top and base reflections from thevertical section pick the top and base reflections from thecandidate reservoir.candidate reservoir.

Do you see any evidence for a flat spot?Do you see any evidence for a flat spot? In one horizontal section, pick the In one horizontal section, pick the downdip downdip limits of the candidatelimits of the candidate

reservoir.reservoir. Go through the identification criteria 1-17 on p. 190 in ch. 5 ofGo through the identification criteria 1-17 on p. 190 in ch. 5 of

BrownBrown (6th ed.) and discuss the evidence that the bright spot is or (6th ed.) and discuss the evidence that the bright spot is oris not a reservoir. (Inline 182 andis not a reservoir. (Inline 182 and Timeslice Timeslice 532 ms shown.)532 ms shown.)