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description:
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This is the point feature class for the once-over landslide inventory of the Tongass National Forest. Most of the landslide polygons were digitized on the 1998 to 2010 orthophotos in GIS. Many of them were age bracketed using air photos back to the 1929 Navy Trimegon photos. It includes both field and photo interpreted landslides. This point layer represents initiation points for debris avalanches, debris torrents, combination-debris avalanches/torrents, slumps, rock fall initiated failures, and rotational failures. There is an accompanying polygon feature class (Tongass_Landslide_Areas), which represents all mass wasting features, including talus slopes, snow avalanche fields, and snow avalanche chutes. |