Digital elevation model of South Fork Toutle River, Mount St. Helens, based on June–July 1980 airborne photogrammetry

The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. The eruption produced mudflows in the South Fork Toutle River basin, which drains the western slopes of the volcano. Orthophotography was acquired shortly after the eruption (June 19 and July 1). Survey extent includes South Fork Toutle River, from its headwaters at Talas and Toutle Glaciers to its mouth at the confluence with North Fork Toutle River near Toutle, Washington. In 2004, Photo Sciences, Inc., under contract to the U.S. Geological Survey (USGS), used softcopy photogrammetry techniques to produce a contour map, breaklines, and masspoints. A USGS aerial solution (year 2000) provided control for the 1980 triangulation. The USGS used these data to produce a digital elevation model (DEM) of the survey area. This USGS data release contains digital elevation and shaded relief data as 4-meter resolution raster datasets (sft_1980dem.tif and sft_1980dem_hs.tif, respectively). The DEM can be used to develop sediment budgets and models of sediment erosion, transport, and deposition.