Correlating logs and traces
Overlay a GeoSyn correlation on a seismic section displayed on a seismic workstation.
Correlation windows and all dialog boxes opened from them float above all application windows, not just those in GeoSyn. You can drag them over a seismic display in any program for comparison.
Open any number of correlation windows. Multiple correlation windows open locked together, and some operations such as zooming or scrolling affect them all.
To maximize clarity and minimize clutter, obvious controls in correlation windows are only available when you right-click the correlation window.
Using the Vertical Scale pane that appears in the Synthetic Properties dialog box, select whether the linear scale displayed in the Correlation window is based on time or depth. Viewing synthetics in depth can be useful to verify the velocity functions upon which a synthetic is derived are accurate.
To correlate logs and traces:
1. To open a single
correlation window, right-click a log (displayed in a single track) or
a trace and select Correlation window
from the pop-up menu
OR
To open multiple correlation windows, from the Utilities
menu, select Create correlation window(s).
The Create Correlation
Window(s) dialog box opens.
Select the traces or logs for which to create correlation windows then click OK. SHIFT+CLICK or CTRL+CLICK for multiple selection.
If you selected more than one Correlation window,
they open locked together. A red horizontal line with yellow triangles at either end indicates the center of the
correlation window.
2. Drag the Correlation window alongside the trace or log to match.
3. Right-click the window and click Set vertical scale from the shortcut menu.
The Set Scales dialog box opens.
4. Do either of the following, and then click Close:
Type a specific increment in the Inches per second box. This distance may not equal physical measured distances because online display is defined in pixels and varies for different monitor resolutions, but the onscreen display should match the same setting defined in other seismic interpretation software.
Click the Center buttons to raise or lower the correlation on a pixel basis.
Click the Zoom buttons to change the distance between the timing lines in the Correlation window. The larger buttons move and zoom the correlation in larger pixel increments.
5. Right-click the Correlation window and click Controls from the shortcut menu.
Depending on whether you displayed the correlation window for a log or trace, either the Log
or the Trace
toolbar appears.
Use the log or trace Toolbar to access a number of dialog boxes, including Log Properties, Display Properties, Tops Properties, Wavelet Properties, and more. The available controls depend on whether a log or trace is selected. Change the controls by clicking a correlation window for either a log or trace.
6. Do any of the following:
To move the log or trace vertically, click and hold the mouse button inside the correlation window and drag up or down.
To match the scale in the correlation window with that of the seismic display program, SHIFT+CLICK inside the correlation window and drag.
To change the trace amplitude, drag the sliders on the Toolbar.
7. Click Stretch and Squeeze.
The Stretch or Squeeze
dialog box opens.
8. Using the model trace, click to define the top of the area on the model to stretch and squeeze, and then click the bottom of the area on the model to stretch and squeeze.
9. Using the Stretch or Squeeze dialog box, drag the slider to elongate or compress the trace within the window defined above.