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Delineating ridges and valleys

October 10 2011 | 0 comments
Categories: Map Data

I have created a curvature raster (combined plan and profile curvature) based on a filtered DEM. I want to delineate ridges and valleys based on the curvature values. I struggle to find a way to implement flat areas where they belong on to the ridges and valleys. Any suggestions?

Attachment showing values from green (negative values) to red (positive values). All flat areas (0) in grey.

Best regards.

Mapping Center Answer:

Curvature is one of the tools people use to derive landforms. In this case curvature is used to help identify the breaks in slope that define the edges of a valley, plateau, etc.

Although I have not tested this myself, there are many different approaches to this that have been developed and there were several good presentations on the topic at the Geomorphometry conference last month http://geomorphometry.org/.

There is a book on the topic, as well as some ArcGIS tools developed by people in the Geomorphometry community:

There is also a link to a free demo version gtb_demoV1.0.6.zip (http://www.ai-relief.org/downloads/gtb_demoV1.0.6.zip).

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