3. Horizontal Event (HE) Filtering
Usually, the scattering feature can be enhanced by filtering out the horizontal arrivals by using the "Horizontal Event (HE)" filtering. For that, select "Process" tab in the BSA display window. Then, right-click the "Filter" button to display the dialog shown below. Check "Save output" and enter "VOID(SR)(CO)(HE=5)" for output file name when prompted as illustrated in the "Save As" dialog.
Choose "Horizontal Events", specify a value (e.g., "5") in the "Horizontal Window (%)", and then click OK button to execute the filtering for all records. A value less than or equal to 5 (%) is usually optimal. A smaller number would be necessary if the horizontal event has the higher dominant frequency, and vice versa. Click "Yes" to display output.
Display normalization option can be changed by using the button (1) in the "View" tab. Surface coordinates of the display can also be chosen for trace number (2), station number (3), and the survey-line distance (3) buttons, last two of which (3 & 4) represent the source-receiver center coordinates.
The following section shows the horizontal coordinate of the center station number between source and receiver for the longest common-offset (29-m) section.