Database for the Geologic Map of the Chelan 30-Minute by 60-Minute Quadrangle, Washington

This digital map database has been prepared by R.W. Tabor from the published
Geologic map of the Chelan 30-Minute Quadrangle, Washington. Together with the
accompanying text files as PDF, it provides information on the geologic
structure and stratigraphy of the area covered. The database delineates map
units that are identified by general age and lithology following the
stratigraphic nomenclature of the U.S. Geological Survey. The authors mapped
most of the bedrock geology at 1:100,000 scale, but compiled Quaternary units
at 1:24,000 scale. The Quaternary contacts and structural data have been much
simplified for the 1:100,000-scale map and database. The spatial resolution
(scale) of the database is 1:100,000 or smaller.

This database depicts the distribution of geologic materials and structures at
a regional (1:100,000) scale. The report is intended to provide geologic
information for the regional study of materials properties, earthquake shaking,
landslide potential, mineral hazards, seismic velocity, and earthquake faults.
In addition, the report contains information and interpretations about the
regional geologic history and framework. However, the regional scale of this
report does not provide sufficient detail for site development purposes.

[Summary provided by the USGS.]