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U.S. Geological Survey Scientific Investigations Map 3123



This digital database was compiled with ArcGIS version 9.3 and consists of files containing geologic map and topographic base data in ESRI geodatabase format. ArcGIS-compatible GIS software is therefore required to use the files of this database.

The database consists of parts of 17 1:24,000 scale U.S. Geological Survey topographic quadrangles. For this data release, the individual quadrangles were merged into one feature class. The entire database was compressed into a WinZip file for ease of transfer. Each zip file contains the metadata for the following layers: quadrangle boundaries, geologic lines and polygons, structure, alteration, caldera boundaries, and rock sample locations. The scale of the source map limits the spatial resolution (scale) of the database to 1:24,000. The topographic bases are raster files in ArcInfo Grid format. Each base is a 1,000 dpi scan of the 1:50,000 county bases for Colorado.

A generalized metadata file for the entire database can be viewed here: Metadata

Also included in this release are two tables in several spreadsheet file formats. These tables contain the Ar-Ar age dates and geochemistry data that were used during the map compilation: table 3 and table 5.

The Database for the Geologic Map of the Cochetopa Park and North Pass Calderas, Northeastern San Juan Mountains, Colorado is contained in the following WinZip file: sim3123_Coch-NP-database.zip







U.S. Department of the Interior
KEN SALAZAR, Secretary

U.S. Geological Survey
Marcia K. McNutt, Director