You can calculate the volume or area between contours either manually or by using a script to automate the process.
- Click Grids | Calculate | Volume.
- In the Grid Volume dialog,
- In the Upper Surface section, toggle Grid File and select a grid-based map from the dropdown list or click Browse to select your grid file.
- In the Lower Surface section, toggle Constant and set the Z= value to the z level of the first contour.
- Click OK.
- Record the Positive Volume value for volumes, or Positive Planar Area value for areas from the report.
- Repeat steps 1-3, using the same grid file as the Upper Surface and the Z level of the second contour as the Lower Surface.
- Subtract the second Positive Volume/Positive Planar Area from the first to get the volume or area between the two contours.
The attached contarea2.bas script calculates the area between evenly spaced contour levels automatically.
To run this script:
- Download the BAS file.
- In a Windows Explorer window, navigate to C:\Program Files\Golden Software\Surfer 15\Scripter.
- Double click on Scripter.exe to launch Scripter.
- Click File | Open, select the BAS file from your downloads directory, and click Open.
- Click Script | Run to run the script.
- Follow the prompts to generate the report.
Updated October 9, 2017