Digital database of the previously published geologic map of the Boulder-Fort Collins-Greeley area, Colorado
This digital map shows the geographic extent of rock stratigraphic
units (formations) as compiled by Colton in 1976 under the Front
Range Urban Corridor Geology Program. Colton used his own geologic
mapping and previously published geologic maps to compile one map
having a single classification of geologic units. The resulting
published color paper map (USGS Map I-855-G, Colton, 1978) was
intended for land-use planning and to depict the regional geology.
In 1997-1999, another USGS project designed to address urban growth
issues was undertaken. This project, the USGS Front Range
Infrastructure Resources Project, undertook to digitize Colton's
map at 1:100,000 scale, making it useable in Geographical
Information Systems (GIS). That product is described here.
In general, the digitized map depicts in its western part
Precambrian igneous and metamorphic rocks, Pennsylvanian and
younger sedimentary rock units, major faults, and brecciated zones
along an eastern strip (5-20 km wide) of the Front Range. The
central and eastern parts of the map (Colorado Piedmont) show a
mantle of Quaternary unconsolidated deposits and interspersed
outcrops of sedimentary rock of Cretaceous or Tertiary age. A
surficial mantle of unconsolidated deposits of Quaternary age is
differentiated and depicted as eolium (wind-blown sand and silt),
alluvium (river gravel, sand, and silt of variable composition),
colluvium, and a few landslide deposits. At the mountain front,
north-trending, Paleozoic and Mesozoic formations of sandstone,
shale, and minor limestone dip mostly eastward and form folds,
fault blocks, hogbacks and intervening valleys. Local dikes and
sills of Tertiary rhyodacite and basalt intrude rocks near the
range front, mostly in the Boulder area.
Complete Metadata
| accessLevel | public |
|---|---|
| bureauCode |
[
"010:12"
]
|
| contactPoint |
{
"fn": "Joseph P Colgan",
"@type": "vcard:Contact",
"hasEmail": "mailto:jcolgan@usgs.gov"
}
|
| description | This digital map shows the geographic extent of rock stratigraphic units (formations) as compiled by Colton in 1976 under the Front Range Urban Corridor Geology Program. Colton used his own geologic mapping and previously published geologic maps to compile one map having a single classification of geologic units. The resulting published color paper map (USGS Map I-855-G, Colton, 1978) was intended for land-use planning and to depict the regional geology. In 1997-1999, another USGS project designed to address urban growth issues was undertaken. This project, the USGS Front Range Infrastructure Resources Project, undertook to digitize Colton's map at 1:100,000 scale, making it useable in Geographical Information Systems (GIS). That product is described here. In general, the digitized map depicts in its western part Precambrian igneous and metamorphic rocks, Pennsylvanian and younger sedimentary rock units, major faults, and brecciated zones along an eastern strip (5-20 km wide) of the Front Range. The central and eastern parts of the map (Colorado Piedmont) show a mantle of Quaternary unconsolidated deposits and interspersed outcrops of sedimentary rock of Cretaceous or Tertiary age. A surficial mantle of unconsolidated deposits of Quaternary age is differentiated and depicted as eolium (wind-blown sand and silt), alluvium (river gravel, sand, and silt of variable composition), colluvium, and a few landslide deposits. At the mountain front, north-trending, Paleozoic and Mesozoic formations of sandstone, shale, and minor limestone dip mostly eastward and form folds, fault blocks, hogbacks and intervening valleys. Local dikes and sills of Tertiary rhyodacite and basalt intrude rocks near the range front, mostly in the Boulder area. |
| distribution |
[
{
"@type": "dcat:Distribution",
"title": "Digital Data",
"format": "XML",
"accessURL": "https://doi.org/10.5066/P95MSFVF",
"mediaType": "application/http",
"description": "Landing page for access to the data"
},
{
"@type": "dcat:Distribution",
"title": "Original Metadata",
"format": "XML",
"mediaType": "text/xml",
"description": "The metadata original format",
"downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.635a935cd34ebe4425047121.xml"
}
]
|
| identifier | http://datainventory.doi.gov/id/dataset/USGS_635a935cd34ebe4425047121 |
| keyword |
[
"Aftonian Interglaciation",
"Boulder",
"Boulder County",
"Boulder Creek granodiorite",
"Bull Lake Glaciation",
"Colorado",
"Colorado Front Range",
"Colorado Piedmont",
"Cretaceous",
"Cretaceous rocks",
"Eocene",
"Fort Collins",
"Front Range Urban Corridor",
"GeMS",
"Geologic Map Schema",
"Geologic map",
"Greeley",
"Holocene",
"Illinoian Glaciation",
"Jefferson County",
"Jurassic",
"Kansan Glaciation",
"Larimer County",
"NCGMP",
"NGS",
"National Cooperative Geologic Mapping Program",
"National Geologic Synthesis Project",
"Nebraskan Glaciation",
"Paleocene",
"Paleocene and Eocene igneous rocks",
"Paleozoic rocks",
"Pennsylvanian",
"Permian",
"Pinedale Glaciation",
"Pleistocene",
"Pliocene",
"Precambrian X",
"Precambrian Y",
"Precambrian rocks",
"Quaternary",
"Quaternary deposits",
"Sangamon Interglaciation",
"Silver Plume quartz monzonite",
"Triassic",
"US GeoFramework Initiative",
"USA",
"USGI",
"USGS:635a935cd34ebe4425047121",
"United States of America",
"Weld County",
"Yarmouth Interglaciation",
"aggregate",
"alluvial gravel",
"eolian sand",
"geologic hazard",
"land-use planning",
"landslide deposit",
"mine subsidence",
"urban growth",
"urban zoning"
]
|
| modified | 2023-10-05T00:00:00Z |
| publisher |
{
"name": "U.S. Geological Survey",
"@type": "org:Organization"
}
|
| spatial | -105.3750, 40.0000, -104.6250, 40.6250 |
| theme |
[
"Geospatial"
]
|
| title | Digital database of the previously published geologic map of the Boulder-Fort Collins-Greeley area, Colorado |
