The Precambrian record of southern Colorado:

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The Precambrian record of southern Colorado an
integrated geologic database in
ArcGIS   Jamey Jones Department of
Geological Sciences, UT Austin GIS Water
Resources Project Presentation December, 2002
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• Objectives
• merge old school field geology with digital
  mapping
• techniques
• merge both large- and small-scale geologic
  mapping with
• published geochronology and other analytical
  data
• create an up-to-data, data-rich yet flexible
  map document
• within ArcGIS to aid geologists working in
  the Precambrian
• of Colorado (especially myself)

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• Why the Precambrian?
• Rocks are extremely old but represent levels of
  exposure
• not seen in recent and modern tectonic
  environments
• (10 20 km deep)
• Relatively well exposed throughout the Rocky
  Mountains
• and southwestern U.S.
• Possible ancient analogs for recent and modern
  mountain belts

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• Data Sources
• the geologic map of Colorado in ARC/INFO format
  (USGS OF-92-507)
• DEM coverage of southern Colorado from the
  National Elevation Dataset
• published and unpublished geochronologic and
  isotopic data for southern Colorado

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Southern Colorado
Wet Mts.
Sangre de Cristo Mts.
500m contour interval
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Sample identification and geochronology
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Relating geochronology and isotopic data
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Analysis and Output
Yg
Xg
Mesoproterozoic magmatism
Paleoproterozoic magmatism
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• Future directions
• expand database/coverage to entire state of
  Colorado and
• possibly all Rocky Mountains and
  southwest U.S.
• expand scope of data to include other
  radiogenic systems,
• geochemical data, etc.
• incorporate new and more detailed mapping into
  basemap
• real-time digital mapping and data collection