This surface was created from a contour map generated from high resolution air photos.  The digital file given to me for my research was imported from AutoCad DXF format into ArcInfo.  The vectors did not have attributes or coordinates, a transformation was performed and AML labeling scripts were applied to generate the geometrically correct DEM you see below.  The contours were forced to fit the USGS quadrangle by means of rubber sheeting.  The registration of the 1995 10 foot contours to the 1947 USGS quadrangle was done after a accuracy assessment, using control points taken with a differential GPS, of the quadrangle found it to be in error of less than 10 feet on average.  The images you see below were created in ArcInfo Tin Modeler and ArcPlot.

Upper Left: Tin with hypsographic shading overlaid with the 10 foot contours used to create it.  This was created by overlaying two screen capture images of the contours and one of the TIN at the same extent, a "transparency" was applied to the contour image and the two images were stacked onto of each other.
Upper Right: Lattice surface overlaid by a mesh grid used for surface orientation  The deep ravine in the center of the image is in places more than 100 feet deep, this feature was captured suprisingly well by the contours. This was created by the same means as the other but the image with the green lines is a "mesh" of the surface, the mesh is used to preview the surface orientation prior to doing a drape of the "hillshade" (the gray scale raster grid with an artificial illumination angle applied) which, for high resolution, can take quite a long time.

These are two views of the 1995 landslide surface.  To the left is an image from above looking down, it shows how deeply the slide cuts into the hill.  Also you can see the prominent edges on the ridge line and how deeply incised some of the drainage's are.
To the right is a view facing the cliff, this surface has a "surfacezscale" applied to it so that the elevation values are stretched.  Stretching height of the surface exaggerates things a bit, but it makes for good visualization because all the erosional features are exaggerated.

To the left is a close-up perspective view that shows the slide, it also shows the dimpled pattern of the interpolated surface.
To the right is another panoramic view with a smoothed surface.

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