ParkSEIS - Bedrock Velocity (Vs and Vp) Evaluation

1. Importing Input File - Dispersion Image [*(*OT).dat]

To open a dispersion image file, go to "Display" → "Dispersion Data [*.dc, *(*OT).dat]" in the main menu as illustrated below.

2. Specify Parameters and Execute Bedrock Velocity (Vs and Vp) Evaluation

Select "Process" tab and then click "F-Sum" as shown above.  It will display the energy summation of the currently displayed dispersion image along the frequency axis (the curve displayed in the chart at the bottom).  A dispersion image below is used as an example.  On first clicking the button, a control dialog (on right) will appear (which can also be invoked by right-clicking the button) that has controls for the summation.  The summation range in frequency (HZ) can be specified in the "Start" and "End" boxes; the phase velocity range can be similarly specified.  Zero ("0") values indicate default values in the input record. The "Min. amplitude to sum (0.0-1.0)" indicates the lowest amplitudes to be included in the summation.  Check the "Display output in a separate chart" box to display the summed curve in a separate chart as illustrated below.  Check the "Save output data (curve) as a file (*.dc)" box to save the summed curve as a file (*.DC) with the same format as an ordinary dispersion-curve file (so that it can be displayed using the same module).  Output file name can be specified by clicking the "Save Output As (*.dc)" button.

To display the phase velocity of a specific peak in the energy summation curve, select the curve (by clicking the curve itself or its title in the legend), depress the "Edit" button, and then depress the "Shift" key while drawing a rectangle around the peak as illustrated below.