How do I find volumes (Cut/fill) above and below a plane (that I've made)?
The scenario is finding tons of rock from either under or over shoveling between blasts. I have two point shapefiles that I have created into elevation grids. One is the surface of the uneven, (actual) shoveled ground, and the other is the "target" digging grade. I'm trying to find the total volumes of rock above and below the "target" plane  which is at an angle.
I see that you can set base heights based on vertices, but there's no way to tell/label the elevation value at certain vertices from an elevation grid, or is there? Also, you can only set base heights based on 'above ground' and 'above sea level' which does me no good.
I've attached a screen shot of the two layers I'm working with. The left image is the uneven ground surface I'm calculating with the shapefile boundary selected. The right image is again, the selected boundary, but with the "target" plane.
I hope this is enough information to find a solution.
I see that you can set base heights based on vertices, but there's no way to tell/label the elevation value at certain vertices from an elevation grid, or is there? Also, you can only set base heights based on 'above ground' and 'above sea level' which does me no good.
I've attached a screen shot of the two layers I'm working with. The left image is the uneven ground surface I'm calculating with the shapefile boundary selected. The right image is again, the selected boundary, but with the "target" plane.
I hope this is enough information to find a solution.
Answers

I'm not sure if my response is a solution to what you are trying to accomplish, and also there are many functions and workflows that I have not learned yet for GM.
For an open pit mine, I had 2 elevation grids representing 2 different strata, and 4 flat areas at different elevations representing quarry levels. To calculate volumes between the strata, I
1. constrained cut/fill to the desired area
2. calculated cut/fill on grid 1 from arbitrary base height that is lower than both grids (i.e. 300m)
3. calculated cut/fill on grid 2 from same arbitrary base height (i.e.300m)
4. subtracted the differences between the two.
I'm sure that there are other work flows that do this same function better. I hope that helped, or that some other GEOPRO can assist.
Categories
 12.8K All Categories
 5.6K Features Discussion
 345 Downloading Imagery
 1.3K Elevation Data
 384 Georeferencing Imagery Discussion
 634 GM Script Language
 54 User Scripts
 114 GPS Features
 416 Projection Questions
 823 Raster Data
 1.3K Vector Data
 6.6K Support
 177 Announcement and News
 911 Bug Report
 558 SDK
 1.2K Suggestion Box
 3.7K Technical Support
 568 Other Discussion
 131 GIS Data Sources
 27 Global Mapper Showcase
 237 How I use Global Mapper
 107 Global Mapper Forum Website