SSO Analysis--Terrain Fabric

Terrain fabric or organization quantifies the degree to which all the ridges and valleys are aligned in the same direction.  This can be indicated by a a value and a direction, and plotted on the map.

Based on an analysis of 50,000 USGS 30 m DEMs, these are the three most highly organized quads in the US. The maps show the ridge valley patterns in the folded Appalachians in Pennsylvania, and a drumlin field in Wisconsin. The lower left diagram shows the contouring of the earth normals, with a strong girdle concentration, which is also apparent in the rose diagram in the lower right. All the normals either point to the NW or the SE.  The dominant ridge direction is to the NE-SW.

The algorithm provides three values: S1S2 or flatness (inverse slope), S2S3 or organization, and the fabric direction.

Detailed discussion of the method.

Terrain organization references.

Last revision 2/6/2017