I was looking for an automated process to "identify" the toe of a slope from a DEM and ran across this ESRI thread and technique:
I am at Step 7 but have no idea how this is accomplished. I get it is in Raster Calculator but how???
Re: Finding toe-of-slope in a DEM
Author William Huber
Date Nov 29, 2003
Message There are a lot of approaches that might be effective. Here's one. Implement it using the Raster Calculator.
(1) Create an indicator grid of "flat" areas. In the example (attached), I have begun with a DEM of part of Highland County, VA. The "flat" areas are those with a slope of less than 6 percent.
(2) Creat an indicator grid of "steep" areas. This is the complement of the flat areas.
(3), (4) Use the indicator grids to mask the original DEM, creating grids showing elevations only where the slope is flat or steep.
(5), (6) Compute neighborhood means of the steep elevations and flat elevations.
(7)Create a "valley edges" grid at cells where the mean of the steep elevations exceeds the mean of the flat elevations.**
(8), (9) Simplify this valley edge grid by performing a Boundary Clean operation, then shrink it by a cell or two.
Any help would be appreciated. Or maybe there is a different way.
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