Petrel Workflow Tools 5 Day Introduction Course Data Import Intro to Petrel Edit Input Data Import data Seismic Well Correlation Fault Modeling Pillar Gridding Zonation and Layering Facies Modeling Petrophysical Modeling Volume Calculation Plotting Well Design Process Manager

Seismic – Data Visualization Objectives Visualize data in 3D, 2D (Base Map) and Interpretation windows Digitize a random line Create arbitrary and aligned seismic random lines Create well intersection fence Tile windows

3D Window Display seismic: Open the seismic cube folder. In-line and Cross-line are available. Add other seismic line types by right-clicking on the seismic cube folder and select the seismic intersection(s). 2. To display a seismic line in the active display window click on the check box in front of a seismic line. 1 Seismic data visualization Toggle on the checkbox in front of the seismic data to visualize the outline of the seismic. Right click on a seismic volume to access the pull-down menu. Here you can choose to create seismic lines, crop a volume, realize a volume, generate attribute volumes, etc. Double-click on the survey to open Settings dialog where the basemap annotation and other display parameters can be modified. 2

‘Base Map’ (2D) Window A Petrel 2D window is used as a seismic base map, allowing you to display and manipulate seismic lines as well as displaying other data (such as wells or interpretations). To create a seismic base map: Open a 2D window. Rename to Seismic Base map 1 3 3. Under the Style tab specify the Base Map annotation. 2. Double-click on the Survey folder to open the Settings dialog. 2 Seismic data visualization  A 2D window will serve as a basemap when the seismic interpretation process is active. Within a “basemap” window you can: Display the frame of the seismic cube(s) with annotations. Display 2D lines with annotation. Display inline, crossline, randomline and time slices. Select seismic lines. Create various arbitrary seismic lines. Display horizon and fault interpretations. Display other data such as wells, well tops etc. 4. Select the check boxes in the Input pane to display seismic lines. 4

Selecting Seismic Lines Method 1 Activate the Seismic Interpretation process and activate the proper cube (bold). Use the icons in the Function bar. A Select line (in-line, cross-line, random line) using the left mouse button. B Method 2 Activate line (in-line, cross-line, random line etc.) in Input pane. Use the player at the bottom of the window. Select in-line. Scroll with the mouse, click with left mouse button to select. Select cross-line. Scroll with mouse, click with left mouse button to select. D Method 3 Click Manipulate Plane icon. Drag in window using Left mouse button. Step through volume Set step/play increment Stop Note: these methods work for both 2D and 3D windows. Play through volume Go to end

Create an Interpretation Window You can interpret in a 3D window or an Interpretation window. There are 2 ways to create an Interpretation window: B A Method 1 Right-click on a seismic line and choose Create Interpretation window. The line will automatically be displayed in the window. D Method 2 Go to the Window menu on the top toolbar and select New Interpretation Window. An empty Interpretation window will appear. To display a seismic line in the Interpretation window toggle on the check box in front of a seismic line C Seismic data visualization The seismic interpretation window gives the user a 2D view of seismic data. Inlines, crosslines and other line types can be displayed in an interpretation window. All interpretation tools are available in this window and the view can be zoomed, stretched, and squeezed in any direction. Inline, crossline and randomline annotations are posted at the top of the window. These lines can be selected by clicking on the small triangle at the top with the left mouse button. Dragging the triangle allows you to change the position of the annotated line. The time-depth scale will show the time or depth in accordance with the project unit settings. Time seismic will be in either seconds or milliseconds and depth seismic will be in meters or feet. If multiple windows are open the displays can be linked. It is also possible to link windows to a visual group to automatically display the same line and the same interpretations in the tiled windows. Note: Time Slices cannot be displayed in an Interpretation Window.

Interpretation Window To Pan, position cursor on the lower, right white bar (horizontal/vertical movement) or anywhere else in window (free movement) - move using the left mouse button. 2 To Zoom, position cursor between the white and the grey lower/right area in the bars and move using left mouse button (or use Left mouse+Ctrl+Shift) 3 1 Interpretation Window It is possible to move and zoom using the same method as used for a 3D window. When zooming with the Magnifying glass, drag a square using the left mouse button. To un-zoom use Shift+Z. If a mouse wheel is available, this can be used for zooming. It is also possible to zoom by positioning the cursor between the white and the grey lower, right area in the bars and move using left mouse button. If the grey area is not displayed, pan sideways or vertical until it appears (lower or right). To Squeeze, hit the line between the grey/white area. Use Shift key + left mouse button to stretch/squeeze Note: It is also possible to zoom using the Magnifying glass in Function bar Drag a square using the left mouse button. To un-zoom use Shift+Z.

Tile Windows Tile the 3D, Interpretation and 2D windows for better overview. Interpretation is updated dynamically between windows. Seismic data visualization Tiling windows: By tiling 3D, 2D and Interpretation windows, a powerful tool for interpreting seismic is obtained. If the same seismic line is selected in all windows, line manipulation is interactively updated in all windows. A world cursor is available for each window under the Windows tab. The world cursor has to be turned on for each active window. Tiling affects the active windows (those checked in the Windows tab). You can also manually resize windows by dragging on the borders.

Random/Arbitrary Seismic Lines In addition to displaying In-lines, Cross-lines and Time slices, you can create random or arbitrary lines through a seismic volume. There are five methods: 1. Automatically. Similar to an in-line or cross-line in that it is a vertical intersection extending through the seismic volume without any bends or turns. 1 2 2. Using an arbitrary polyline intersection. In a 3D or 2D window, you define the desired path of the line. 1. Activate the Seismic Interpretation process. 2. If using a 3D window, post an object (e.g., timeslice). Not required in a 2D window. 3. Click on the ”Create arbitrary polyline intersection” or the ”Seismic aligned polyline intersection” icon. 4. Draw the polygon using the left mouse button and stop by double clicking. The vertical seismic intersection will automatically be displayed. 5. The general seismic intersection together with the polygon will be put under the Input tab in the Petrel Explorer window. 6. To edit the intersection, activate the Make/Edit Polygons process, activate the Arbitrary polygon and toggle on the ”Select and Edit/Add points” icon in the Function tool bar. 7. Edit a point or the whole polygon line and the seismic intersection will be changed according to the polygon. 3 3. Using a seismic aligned polyline intersection. Similar to an arbitrary polyline intersection, you define the desired turning points but the path between points is snapped to either the in-line or cross-line direction.

Random/Arbitrary Seismic Lines 4. Using a combination of arbitrary and aligned polylines. Same process as for 2, use the Ctrl key to snap to either the in-line or cross-line direction. 4 5. Between selected wells. This is called a Well Intersection Fence. 5 If several surveys exists (2D and 3D seismic) and you want to display a line going from one survey to the next, composite lines can be made.

Wells – Displaying Data in Time In order to display well data in time, a time-depth relationship for each well is required. The general procedure is: Load velocity data for wells (e.g. check shots, sonic logs, etc). 2. Create time log for each well. This will determine the time-depth relationship to use for displaying well data in time. 3. Display well bores. Seismic data visualization A time-depth relationship is required to post well bores and other well data in time. 4. Set domain and display picks and fault cuts.

Wells – Import Check Shots 1. Create check shot folder by going to Insert >New Check Shots. 1 3 4 2. Right-click on the Check Shot folder under Wells and select Import (on Selection). 2 3. Select file(s) and format and click Open. Check Shots Check shots are time-depth pairs for a borehole obtained by analyzing the first seismic arrival for known depths in the borehole. They are used to obtain a time-depth relationship for the borehole and are the best source of time-depth data for generating synthetic seismograms. Check shot data can be imported with one file for each well or with a single file for all wells. Like Wells and Well Tops, check shot data must be loaded into a Petrel specific folder. The process for importing check shots is identical to that for loading well tops. If the file does not have a column containing a well name, Petrel will assume that a single file is used for each well. It will then attempt to attach the check shot file to a well based on the file name; the user can override this and manually select the well if necessary. As with deviation surveys and well tops, check shot data can be edited using the spreadsheet. Right click on the Check Shot folder and select Spreadsheet. 4. Adjust parameters if necessary and click OK.

Wells – Create time logs 1. Double-click on Wells folder to open Settings dialog. 1 3 2 2. Go to Time tab. If there are multiple entries, make sure the preferred time-depth relation is first on the list, toggle on and Execute, click OK. This will determine the time depth relationship used for displaying the wells in time. All the possible sources of such a relationship (check shots, well tops, sonic logs etc.) are listed in the window and can be set in order of preference. For each well, the highest available item on the list will be used as the time depth relationship. Manual adjustment can be used to stretch or squeeze the time section by adjusting the time depth relationship. This is used when events can be correlated between the synthetic seismic and the 3D seismic cube or a 2D line. Override settings on all wells in this folder can be used to change the settings for a particular folder of wells. 3. A time log will be created for each well.

Wells – Display Boreholes in Time 1. Toggle on the check box next to the Wells folder to display all wellbores. Alternatively, expand the Wells folder and toggle on individual wells. 2. Adjust display parameters by double-clicking on the Wells and Well attributes folder, going to the Style tab. 2 1

Wells – Display Well Tops in Time 2 1. In the top toolbar, change the domain to TWT. 1 3 2. Toggle on the check box next to the Well Tops folder. Expand the Attributes folder under the Well Tops folder. Toggle on TWT Auto attribute. Visualization Domains (ANY, TWT, TVD) The default domain setting is Any which is unitless. All data can be displayed and the volume dimensions will be adjusted so the data are visible. No conversion from time to depth (or visa versa) is performed. Changing the domain to TWT or TVD will limit data which can be displayed. For example, if the domain is set to TVD and you attempt to display seismic data, unless you have a depth cube loaded, you will not see any seismic displayed. Display of wells is similarly affected, if you do not have a time-depth relationship built (e.g. a time log in the wells), well data will not display if the domain is set to TWT. Use as visual vertical position – Right-click on an attribute and choose Use as visual vertical position. This function will set the selected attribute as the vertical position for the 3D display and drawing of the data.  The chosen attribute will appear with purple text in the Input pane. This switches the display to a user defined domain on the active display window. The user can now choose to display wells and well tops both in time and depth if the time-depth relation has been established. Attributes: TWT Picked – user specified two way time. These values will not change if the time-depth relationship defined for a well is edited. TWT Auto – two way time calculated from the measured depth picks using the time-depth relationship defined for a well. If the time-depth relationship or the measured depth is edited, these values will be updated. 4

Random Lines – Well Section Fence 1 Random Lines – Well Section Fence How to create a Well Section Fence 2 Open a new Well Section Window from the windows menu. Go to the Wells folder and toggle the wells you want to include. 3 2. The Well Section Fence is placed in the Well Section folder in the windows tab, only active when 3D window is open. 4 3. Click on the blue button: Toggle visualization on plane. Well Intersection Fence This is an arbitrary seismic line connecting selected wells. You can interpret horizons and faults on a well intersection fence. 4. Click on the blue check box in front of the Seismic 3D cube.

EXERCISE Seismic Visualization