CONTRIBUTIONS TO THE SIERRA NEVADA DIGITAL EARTH SCIENCE ATLAS: DIGITAL COMPILATION OF GLACIAL AND LANDSLIDE DEPOSITS IN THE SIERRA NEVADA

As part of the Sierra Nevada Digital Earth Science Atlas (SNDESA) project, the California Geological Survey (CGS) has undertaken a new effort to compile glacial and landslide deposit mapping in the Sierra Nevada. Mapping has been compiled from various authors and agencies, such as the CGS, the U.S. Geological Survey, the National Park Service, the U.S. Forest Service, and the Nevada Bureau of Mines and Geology.

The near-term goal of this effort is to produce a generalized depiction of glacial and landslide deposits to be shown on a 1:400,000-scale geologic map covering the entire Sierra Nevada. Due to the limitations presented by the map scale and the lack of consistent range-wide mapping, the glacial deposits shown on the SNDESA geologic map consist of one map unit, “Glacial deposits, undifferentiated”. Similarly, the generalized depiction of landslide deposits also consists of one map unit, “Landslide deposits, undifferentiated”. However, details from compiled mapping were retained for future use, including age of deposit (or glacial stage, where applicable) and lithologic description. Source maps mostly range from 1:48,000 to 1:100,00-scale, but some smaller- and larger-scale maps were also utilized. The compiled data is stored in a spatial database that will be updated as additional mapping is discovered.

Longer-term goals include the development of a public-facing web map for the glacial deposits of the Sierra Nevada that will allow users to display and interact with the detailed data. The map is intended to be a resource for researchers, professional and amateur geologists, and those interested in the glacial geology of the Sierra Nevada.