Data release for Geologic Map of the Poncha Pass Area, Chaffee, Fremont, and Saguache Counties, Colorado
Dates
Publication Date
2019-08-28
Time Period
2019
Citation
Minor, S.A., Brandt, T.R., Caine, J.S., and Ruleman, C.A., 2019, Data release for Geologic Map of the Poncha Pass Area, Chaffee, Fremont, and Saguache Counties, Colorado: U.S. Geological Survey data release, https://doi.org/10.5066/P9GYYF4F.
Summary
This release presents the GIS data (in GDB, shapefile, and e00 [coverage] formats) and metadata for a 1:24,000-scale geologic map of the Poncha Pass area in central Colorado. A cartographic version of the geologic map, including map unit descriptions, interpretative text, and accessory figures and tables, is being separately published as a U.S. Geological Survey Scientific Investigations Map (SIM). The map area is irregular in shape, covering all of one 7.5' quadrangle (Poncha Pass) and parts of five others (Mount Ouray, Maysville, Salida West, Salida East, and Wellsville). The map boundaries were drawn to cover all of the "Poncha mountain block", coincident with the approximately 15-kilometer-long northwestern end of the Sangre de [...]
Summary
This release presents the GIS data (in GDB, shapefile, and e00 [coverage] formats) and metadata for a 1:24,000-scale geologic map of the Poncha Pass area in central Colorado. A cartographic version of the geologic map, including map unit descriptions, interpretative text, and accessory figures and tables, is being separately published as a U.S. Geological Survey Scientific Investigations Map (SIM). The map area is irregular in shape, covering all of one 7.5' quadrangle (Poncha Pass) and parts of five others (Mount Ouray, Maysville, Salida West, Salida East, and Wellsville). The map boundaries were drawn to cover all of the "Poncha mountain block", coincident with the approximately 15-kilometer-long northwestern end of the Sangre de Cristo Mountains. The map data convey the areal distribution of: (1) Proterozoic basement rocks forming the core of the Poncha mountain block, (2) overlying Tertiary volcanic rocks, (3) Miocene and younger basin-fill deposits, (4) Quaternary surficial glacial and alluvial deposits, and (5) faults and folds affecting all of the above units.
Land-use planners of many kinds (including National Forest managers, developers, city and rural planners, and highway builders) as well as resource exploration and management operations need accurate geologic map data to make informed decisions. The geologic map compilation of the Poncha Pass area directly addresses this need. Also, the map is part of the National Geologic Map Database, which constitutes a digital geologic framework for the entire country. From a scientific standpoint, the map addresses several geologic questions of the enigmatic, intrarift Poncha mountain block that separates the southern Upper Arkansas River Valley from the northern San Luis Valley. The Poncha Pass area map provides new details of the geology of this poorly understood area and helps elucidate the development of the Poncha block and improves understanding of the geologic framework and geologic history of the area.
Preview Image
Graphical representation of the geologic map of the Poncha Pass area, Colorado
