I would like to know if there is a simple geoprocessing sequence to get landslide initiation points from these layers:
I think that there might be a creative solution (like reversing the elevation and then using raster hydrology tools), but I am not familiar enough with ArcHydro to see what it is.
I have already considered these methods:
A geologist examines each of over 24k polygons and digitizes the initiation points individually.
This is the right way to do it, but too expensive.
Write a python script from scratch that does this.
Sounds like fun, but I don't have the time.
Use zonal statistics.
This seems like it would be the right answer, but it has 2 problems:
The raster resolution is so coarse that some small landslides may be lumped with big ones.
Attachment 29723
Some polygons have multiple initiation points.
Attachment 29724
- SRTM DEM (90m)
- Landslide polygons (many different sizes and shapes)
I think that there might be a creative solution (like reversing the elevation and then using raster hydrology tools), but I am not familiar enough with ArcHydro to see what it is.
I have already considered these methods:
A geologist examines each of over 24k polygons and digitizes the initiation points individually.
This is the right way to do it, but too expensive.
Write a python script from scratch that does this.
Sounds like fun, but I don't have the time.
Use zonal statistics.
This seems like it would be the right answer, but it has 2 problems:
The raster resolution is so coarse that some small landslides may be lumped with big ones.
Attachment 29723
Some polygons have multiple initiation points.
Attachment 29724