Background on Kingdom Suite for the Imperial Barrel Competition 3D Horizon/Fault Interpretation Parts 1 & 2 - Fault Interpretation and Correlation

Transcription

1 Background on Kingdom Suite for the Imperial Barrel Competition 3D Horizon/Fault Interpretation Parts 1 & 2 - Fault Interpretation and Correlation Wilson (2010) 1

2 Fault/Horizon Interpretation Using Seismic Micro-Technology s Kingdom Suite 3D Workshop Labs 1& 2 First > Copy the BEG folder (or Maersk if you are working the Barrel) to your G:\Drive. These folders contain 3D seismic data. Seismic Micro-Technology's Kingdom software is accessed through the Windows Start Programs Menu. In your program list select Kingdom Suite and then left-click on Kingdom. NOTE: Left click to start, continue and end an activity. Right clicking is ONLY used for displaying various pop-up menus. You will probably be asked to select a network license. Turn on the upper radio button as shown below. 2

3 The following page will come up when Kingdom is initiated. LC > Open Project Navigate to your G:\Drive and enter either the BEG or Maersk folders 3

4 . Project files are opened from the initial Kingdom Suite window (Figure 1). Click on Project then Open Project in the drop-down menus. Take a moment and Copy the folder Golden from your H:\drive to your G:\drive Figure 1: The initial Kingdom Suite display window provides access to new and old project files. 4

5 If you are in the BEG folder open the BEG.tks file on your G:\drive. Otherwise open the MaerskEsplanaden file. When you open the folder, the tks file should appear in the the open file dialog box. Highlight the GOLDEN.tks file (or tks file identified for use in this class and open it. The following window will contain an author list box and give you the option to create your own project. For this class, click on Create and enter your last name or other preferred identifier as shown below. 5

6 Select the author you just created and then click OK. The following illustrations are general illustrations associated with the BEG (or Golden) data sets. The workflows outlined in the following tutorial can be followed in the analysis of just about any 3D data set. 6

7 This exercise uses the Golden (or BEG) 3D data set, which is provided through the network drive. In this exercise, the "green reflector you interpreted on the 2D lines running through the area will be interpreted and carried through the 3D coverage of the area. The entire 3D grid is interpreted. In this exercise, the major faults are interpreted at the outset, since this will prevent autopicking of select reflection events across fault planes. Procedures: When you open a project under Kingdom, the basic windows layout will contain a 3D basemap (right) and project tree (left) (Figure 2). Figure 2: Basic window layout showing project tree and 3D grid basemap. 1. Left click on the 3D grid (Figure 2) to activate it. Line and crossline numbers are plotted along the sides of the basemap. In this example, position the mouse arrow on Line 110. Right click and select Display In- Line 110. The seismic line may now appear as shown below in Figure 3. 7

8 *Color display options will be covered in class, so you might want to take some notes. Figure 3: Wiggle trace display of 3D line 110. Display parameters are easily changed using the tool bar across the upper left corner of the seismic display window. To transform the seismic response into a color display, click on the little scale bar in the tool bar (see below). That should bring up the following window - 8

9 In the settings window you ll see several folders ( Horiz. Scale, Vert. Scale, Display Options, etc.) Open the Display options folder and select Hi Res Color Raster and then OK. You may continue to get a black and white display of your data, butit is in raster form. To use a different color scheme click on the color bar editor (see below) And in the window that opens, click on the little open folder icon or on Color Bar and then select. In the window that opens up select blue to brown to white to brown 200.clb and then OK. The following window will appear. 9

10 The variable area wiggle traces that are superimposed on the color raster can be switched off by clicking on the wiggle lines in the upper left corner of the seismic display window which will open up the following window. Select No Overlays and then OK to get the following window. 10

11 2. If you prefer another colorbar, left click on View and Colors. Click on File and Open and select a different colorbar. In most cases, the name of the colorbar describes the colors and the number of colors in the colorbar. You can also use the left and right blue arrows in the color-bar select window to move through the color bars one-by-one. Close the color editor once you are satisfied with a colorbar. 3. To get back to wiggle traces, left click on View, Settings and then select the Display Options folder and then select Wiggle Variable Area. Or you can go there directly as before by clicking on the scale bar in the seismic display window as done before. Note the other display formats for future reference. You can also change the trace amplitudes in the wiggle trace display by using the F5 key to increase amplitude and the F6 key to decrease amplitude. Your variable area wiggle trace display should look something like that shown below in Figure 4. 11

12 Figure 4: Variable area wiggle trace display format of Line For additional changes to the display scales, left click on View and Settings or click on the scale bar at the top of the seismic line display window. Then go to Horiz. Scale and try 8 traces per inch and Vert. Scale = 10 inches per second to provide a close-up (Figure 5) view of waveform character in the vicinity of the well shown above (Figure 4). Use the scroll bars to position yourself within the line. Figure 5: Close-up view obtained using 8 traces/ inch and 10 inches/second. 12

13 5. You can orient yourself to geographical directions by moving the cursor on the seismic window (Figures 4 or 5) and watch the cursor movement on the map. If the direction is backwards hit the R key on the keyboard to reverse the line direction. 6. The colorbar may or may not be displayed on the seismic window. To display colorbar, left click on View and Toolbars and then Color Bar. A check indicates on. You can also add and remove the color bar directly from the seismic display window by clicking on the color bar icon circled below. Figure 6: Shortcut buttons on the line display window. Buttons, left to right, select seismic line, wiggle overlay, vertical seismic display scale, color bar editor, a toggle switch to display the color bar, and two zoom control buttons. The drop down window at right allows the user to select from time or other data type. 7. Display features can also be accessed directly using the buttons (Figure 6) in the upper left corner of the trace window. 8. On the seismic line, several faults are prominent. Many of these faults are easy to correlate others are not. Now would be a good time to assign a name to at least two of the major faults, the down to the south synthetic and down-to the north antithetic faults. To assign the faults, right click on the seismic window and select Fault Surface Management. From there, select the Create tab and enter a name and color for the antithetic fault. Left click on Apply. Enter a name and color for the major fault and then either OK or Apply. Create new faults if desired, You're now in the fault picking mode with the last created fault active. Before we proceed, note that I have changed the color bar to Landmark.CLB. My display (see below) was set to Horiz. Scale = 20 traces per inch and Vert. Scale = 3.5 inches per second. Click on the R button so that cross-line numbers run from 120 to 0, left to right across the seismic display window. You re welcome to choose different display parameters. Don t forget that you can also adjust the relative amplitude of the traces using the F5 and F6 keys. Take a few moments and experiment. 13

14 9. Display the fault toolbar to allow for quicker selection of the faults you wish to pick. To do this left click on View and Toolbars and then Faults. All the displayed faults are present, including Unassigned. Hot keys are available: D enters the user into the fault digitization mode, A assigns a fault, and "S" de-assigns. 10. To start picking your fault, left click on one of the fault names. To begin digitizing hit the D-key; then start at the top of the fault and begin left clicking on the fault break that courses through the seismic data. A rubber band should appear as you go from point to point (Figure 7). Continue left clicking points along the fault until you either need to scroll vertically or horizontally to view fault extensions outside your current view (Figure 7). You can use the scroll bar to move the display so that more of the fault is visible, however, it is easiest just to hold the mouse arrow about a quarter of an inch above the bottom of the display window, which will cause the display window to slide down. Continue until you can no longer pick this fault. Double click to end. If you enter a point you don t like, you can back up or delete the last point by hitting the Esc key 14

15 Figure 7: Individual points digitized along the fault appear as black squares connected by a thin black line (or rubber band). 11. Left click on the other fault displayed in the Faults digitizing menu to activate it and then hit the D" key to begin digitization. Begin picking the second fault. If you choose to pick some of the other faults on the Faults Toolbar, simply activate the appropriate named or unassigned fault, hit the D key and start picking. The two faults you just picked should appear as shown in the montage below (Figure 8). The number of points used to digitize the fault will vary from interpreter to interpreter. 15

16 Figure 8: Project tree (back left) and basemap (right) lie in the background behind seismic Line 110 (right) and the Faults menu (small window at left). Faults just digitized on the northern end of the line appear as shown above. 12. The fault remains active so long as the square dots are present. If the fault is not active and you want to edit it, just click on it. When a fault is selected for further editing, little handles appear on each digitized point. To move points, activate the fault and then left click-and-hold on the digitized fault point. As you move the mouse, the digitized point will also move. If you move a small distance, you may have to use the Esc key to undo the rubber band. 13. If you would like to move the entire fault line, first activate the fault and then hold the Ctrl key and then left click and hold on any part of the fault line. Move the line to wherever you like and then release the mouse button and Ctrl key. 16

17 14. To delete a fault segment, make it active and then hit the delete key on your keyboard. 15. To add points, left click on an existing point, add the appropriate intervening points, and double click on another existing point. 16. To remove consecutive points, left click on an existing point, skip the 'bad' points and double click on an existing point. 17. If you'd like to change the active fault, left click on the new fault to activate it or select from the Faults Menu. If the new fault has no existing digital points, you must hit "D" on either the keyboard or Faults Menu. 18. To assign an unnamed fault, activate the fault name, activate the unassigned fault line and then hit the A-key. 19. To de-assign a named fault, activate the fault line and then hit the S-key. 20. Once the faults have been picked on this line, you can begin picking the faults on a grid of lines extending through the entire 3D data base. The interpretations are usually made every few lines. You can skip through the data base a constant number of lines each time. To set the skip increment left click on View, then Settings, and then open the Seismic folder. In the Seismic folder you can Set Line Skip Increment to 20 and then OK. (Note a much easier way to do this is to type the number directly into the window that sets between a couple blue arrows at the top of your seismic display window. Now whenever the right arrow on the keyboard is hit, the line displayed will increase by 20. If the left arrow is hit, the display will decrease by 20. If a cross line is displayed, the up and down arrow keys will work likewise. 21. Go to line 130 and digitize the main down-to-the-south fault and antithetic fault. 17

18 22. Once an assigned fault has been picked on at least two lines, a fault surface is automatically created. To view fault surfaces in map view go to the Project Tree and double click on the appropriate fault icon (Figure 9). This opens a new map window where the fault may be displayed as either a fault surface or segments. Double Click Figure 9: To display a fault surface double click the desired name listed in your project tree. Map view of fault surface is shown below (Figure 10). Figure 10: The large down-to-the-south fault is displayed in map view. Colorcoded two-way travel times appear in the color bar at right. 18

19 At this point your interpretation consists of only one line. At this point, complete your fault interpretations. Carry both the synthetic and antithetic faults through the entire 3D data cube. Once you ve completed your fault interpretation, you should have a more complete view of travel time variations to individual fault surfaces. To toggle from planes to segments, go to View, Fault Display Mode and select either Fault Surface or Fault Segment. The fault segment display is shown below in Figure 11. Figure 11: Fault segment display of the main down-to-the-south fault. 23. Display features can also be accessed directly using the buttons (Figure 12) in the upper left corner of the map window (Figure 11). 19

20 Note Fault Surface is selected in the window at right (see Figure 12 below). Figure 12: Shortcut buttons available on the map display window. Buttons, left to right, allows the user to Select fault surface to display, Select Contour Overlay, Set Contour Parameters, Set Scales, Edit Colorbar, Show Colorbar, magnification control buttons, and a selection window that allows you to switch back and forth from Fault Surface and Fault Window displays. In the fault segment display shown below for the antithetic fault, note that my picks for the fault on lines 110 and 120 appear out of place. Take a close look at your own correlations at this point and try and resolve any misinterpretations that might have occurred. 20

21 24. Display the fault surface in seismic view so that any miscorrelation can be quickly seen. To do this, go to a seismic window and right click, go to Fault Surface Management, and then Display. In the Display window verify that Both is selected for Display Type (Figure 13). If Both is selected, two lines are visible in seismic view, the straight line connecting the digitized points and the interpolated fault surface. Figure 13: Fault Management window. Select Both to display both the individual fault-trace picks and the interpolated line fit to these points (see step 24 above). Make corrections to your interpretation if needed and proceed. 21

22 25. Complete fault picking: Be sure to extend your interpretations east to Line 145. Note that the solid green line that now appears on the seismic displays represents and interpolated or extrapolated fault surface (Figure 14). This projection is displayed as a guide only and does not represent the actual fault surface. When complete return to line 90 and continue to the west. To go to line 90, left click on Line and then Select or left click on the arrow button in the seismic display window which brings up the same window. Type in 90 and be sure the line button is on and that the 3D survey is displayed. Hit OK. If you would like to view the faults in strike direction or on an arbitrary line, right click on the desired cross line in the base map window and then display line. Figure 14: Interpolated fault surface shown as solid green line on seismic Line

23 Again to display the fault surface make sure fault surface is selected in the text box to the right of the toolbar on the fault surface display. The map of your antethetic fault should look similar to that shown below. 26. To display line with an arbitrary orientation through the survey, right click on a map window, select Digitize Arbitrary Line, left click on the starting point, continue left clicking on each bend in the line (Figure 15) and then double click to end. The digitized line will appear (Figure 16). 23

24 Figure 15: An arbitrary line overlay is extracted from the 3D survey using the digitize arbitrary line option. Remember that the solid green line is the interpolated antithetic fault surface and it may jump around quite a bit between lines where the fault surface was digitized. Take a close look at your arbitrary line. 24

25 Figure 16: Arbitrary 2D line digitized in Figure 15. Note that along our arbitrary line some of the features showing up in the time map are associated with errors in the interpolation. The high (blue color) and low (red color) area adjacent to each other on the southeast end of the arbitrary line are clearly associated with errors in the interpolation. Note that the colors indicate that the fault drops abruptly south from 0.4 seconds to more than 2 seconds. We made our initial interpretations on a course grid, every 20 lines through the 3D database. At this point, take some additional time and make your interpretations every 10 lines; then recheck your time map using the digitize arbitrary line option or by selecting appropriate In-Lines and Cross-Lines. 25

26 At this point, your fault surfaces will be correlated across the entire survey area. The north-dipping (antithetic) fault surface, for example, will appear as shown below (Figure 17). Figure 17: Color raster display of north-dipping (antithetic) fault surface. 27. Continue picking faults, in the western direction. You can edit interpolated fault picks by first selecting the desired fault as the active fault in the Fault Management Window, and then hitting the D key to digitize. If you wish to correct a portion of the interpolated picks simply begin picking points through the desired region. Double click to complete digitization. Your picks will replace the interpolated picks. Note: If a fault has been extended too far, you can delete a portion of the interpolated fault line by digitizing the extended portion, and double clicking to replace the interpolated line with your picks. Then click on the bad pick and drag the rubber band to the first good pick and double click. All points beyond the last pick will be deleted. In the next segment we will carry the 1.3 second reflector through the 3D data set. 26