Digital Geologic Map of the Butler Peak 7.5' Quadrangle, San Bernardino County, California

This data set maps and describes the geology of the Butler
Peak 7.5' quadrangle, San Bernardino County, California.
Created using Environmental Systems Research Institute's
ARC/INFO software, the data base consists of the following
items: (1) a map coverage showing geologic contacts and
units,(2) a scanned topographic base at a scale of 1:24,000,
and (3) attribute tables for geologic units (polygons),
contacts (arcs), and site-specific data (points). In
addition, the data set includes the following graphic and
text products: (1) A PostScript graphic plot-file containing
the geologic map on a 1:24,000 topographic base accompanied
by a Description of Map Units (DMU), a Correlation of Map
Units (CMU), and a key to point and line symbols; (2) PDF
files of the DMU and CMU, and of this Readme, and (3) this
metadata file.
The geologic map data base contains original U.S. Geological Survey data
generated by detailed field observation and by interpretation of aerial
photographs. The map was created by transferring lines from the aerial
photographs to a 1:24,000 mylar orthophoto-quadrangle and then to a
base-stable topographic map. This map was then scribed, and a .007 mil,
right-reading, black line clear film made by contact photographic
processes.The black line was scanned and auto-vectorized by Optronics
Specialty Company, Northridge, CA. The non-attributed scan was imported
into ARC/INFO, where the database was built. Within the database, geologic
contacts are represented as lines (arcs), geologic units as polygons, and
site-specific data as points. Polygon, arc, and point attribute tables
(.pat, .aat, and .pat, respectively) uniquely identify each geologic datum
and link it to other tables (.rel) that provide more detailed geologic
information.