How do I find volumes (Cut/fill) above and below a plane (that I've made)?

AustinGeo

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.

Marshall

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.