High-resolution digital elevation model for Mount Adams and vicinity, Washington, based on lidar surveys of August-September, 2016
Description
Mount Adams, also known by the Native American names "Klickitat" or "Pahto", is a 3,742 meter-tall (12,278 feet) stratovolcano located 53 km (33 miles) north of the Columbia river straddling the borders of Skamania County, Yakima County and the Yakama Nation Reservation. Mount Adams lies in the middle of the Mount Adams volcanic field—a 1,250 square kilometer area (about 480 square miles) comprising at least 120, mostly basaltic volcanoes that form spatter and scoria cones, shield volcanoes, and some extensive lava flows. The volcanic field has been active for at least the past one million years. Mount Adams was active from about 520,000 to about 1,000 years ago and has erupted mostly andesite. Eruptions have occurred from ten vents since the last period of glaciation about 15,000 years ago. The volcano has produced a larger volume (about 300 cubic kilometers or 70 cubic miles) of eruptive material during the past million years than any other Cascade stratovolcano, surpassed only by Mount Shasta (about 350 cubic kilometers or 85 cubic miles). Approximately 6,000 and 300 years ago, debris avalanches from the southwest face of Mount Adams generated clay-rich lahars that swept more than 30 square kilometers (11 square miles) south of the volcano along the White Salmon River. The summit of Mount Adams contains a large section of unstable, hydrothermally-altered rock that can spawn future debris avalanches and lahars. This DEM (digital elevation model) represents the ground surface beneath forest cover of Mount Adams and adjacent vicinity. It is the product of high-precision airborne lidar (Light Detection and Ranging) surveys conducted during August and September of 2016 by Quantum Spatial under contract with the USGS; total area is 2278.6 square kilometers (879.8 square miles). This release consists of DEM and corresponding hillshade rasters. The survey area is divided into four sections: adams_edifice.tif, adams_indian_heaven.tif, adams_west.tif, and adams_east.tif. Hillshade images are spatially coincident to the DEM from which they are derived. Filenames appended with the suffix “_hs” indicate hillshade images (e.g. adams_edifice_hs.tif).