Filters: Tags: North Fork Toutle River (X)
2 results (8ms)
Filters
Date Range
Extensions Types Contacts
Categories Tag Types Tag Schemes |
The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980-1986 and 2004-2008. During 2017, U.S. Forest Service contracted the acquisitions of airborne lidar surveys of Mount St. Helens and upper North Fork Toutle River basin, part of a larger 2017-2018 survey of the Gifford Pinchot National Forest. The U.S. Geological Survey combined and reprojected 81 raster datasets, provided by the U.S. Forest Service in October 2018, into a single digital elevation model (DEM) of the ground surface, including beneath forest cover (that is, 'bare earth')....
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: ALS,
Cascade Range,
Cowlitz County,
DEM,
Ecology,
This digital terrain model represents historical elevations along the valley of the North Fork Toutle River upstream of its confluence with the Green River in Cowlitz and Skamania Counties, Washington. Most elevations were derived from U.S. Geological Survey 1:62,500 scale topographic quadrangle maps published from 1953 to 1958 that were derived from aerial photographs taken in 1951 and 1952. Elevations representing the bed of Spirit Lake, at the head of the valley, were derived from a bathymetric map based on survey data from 1974. Elevations are in units of meters and have been adjusted to the North American Vertical Datum of 1988.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Cowlitz,
Cowlitz County,
Geography,
Lower Cowlitz,
Mount Saint Helens,
|
|