Peter N. Schweitzer
2011
Combined geologic map data for the conterminous US derived from
the USGS state geologic map compilation
0.1
http://tin.er.usgs.gov/geology/state/geol_poly.zip
The State Geologic Map Compilation was an effort by USGS to assemble
state geologic maps and arrange their attribute data in a consistent
database structure with, as much as practical, consistent category
terms for the most critical attributes. Those data are provided on
the web in separate data packages for each state, as they were
published by USGS. This data set rearranges those data with a small
subset of descriptive attributes, one of which is a hypertext link
to an online description of the geologic map unit.
Provide geologic map data for the conterminous US rather than one
data package per state. Data are approximately compiled at
1:500,000 scale so are appropriate for analysis of large regions
within the conterminous US, and will be less satisfactory for the
analysis of local areas such as counties.
20110922
Date the information was drawn from the master database
Complete
As needed
-126.489840
-66.742745
49.384519
24.276909
USGS Thesaurus
rocks and deposits
geologic maps
geologic history
none
none
Peter N Schweitzer
USGS ER GD
Geologist
mailing address
12201 Sunrise Valley Drive
Reston
VA
20192-0002
USA
703-648-6533
703-648-6252
pschweitzer@usgs.gov
PostgreSQL with PostGIS under Linux
Because these data have been inherited from more detailed maps at
the state level and below (during the compilation of the state maps
themselves from much more specific source maps) accuracy of the
attributes is mixed with consistency of definition (of the units)
and decisions made by many people regarding the level of detail to
report or retain from previous reports. Consequently an overall
summary of accuracy cannot be given.
These data were drawn from state geologic maps in which the geological
concepts varied from state to state. For example, some maps focused
more on showing surficial geologic units, while others ignored the
surficial units and focused on bedrock. Some metamorphic terranes are
described using the protolith or source rock prior to metamorphism.
In many cases geologic units in one state correlative with those in
another were grouped in one and described separately in another state,
so that "state line faults"--apparent changes in lithology at the
state border--appear due to slight differences in geologic description
and the extent of geological generalization. The USGS compilation of
the state maps did not attempt to reconcile these differences.
The entire land area of the conterminous US is described by these
data. In some states the geologic units extend beneath water bodies
while in others the areas covered by water are simply described as
water.
State geologic maps were generalized to approximately 1:500,000
scale, so the positional accuracy of any specific geologic contact
is likely to be generalized and therefore plotted within tens or
hundreds of meters from where the contact might be found on more
detailed maps or aerial photographs.
Nicholson, Suzanne W.
Dicken, Connie L.
Horton, John D.
Foose, Michael P.
Mueller, Julia A. L.
Hon, Rudi
2006
Preliminary Integrated Geologic Map Databases for the United States:
Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, Rhode
Island and Vermont
Open-File Report
2006-1272
Reston, Virginia
U.S. Geological Survey
http://pubs.usgs.gov/of/2006/1272/
500000
digital GIS data files
2006
publication date
ofr20061272
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Dicken, Connie L.
Nicholson, Suzanne W.
Horton, John D.
Kinney, Scott A.
Gunther, Gregory
Foose, Michael P.
Mueller, Julia A. L.
2005
Preliminary integrated geologic map databases for the United States :
Delaware, Maryland, New York, Pennsylvania, and Virginia
Open-File Report
2005-1325
Reston, Virginia
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1325/
500000
digital GIS data files
2005
publication date
ofr20051325
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Dicken, Connie L.
Nicholson, Suzanne W.
Horton, John D.
Foose, Michael P.
Mueller, Julia A. L.
2005
Preliminary integrated geologic map databases for the United States :
Alabama, Florida, Georgia, Mississippi, North Carolina, and South
Carolina
Open-File Report
2005-1323
Reston, Virginia
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1323/
500000
digital GIS data files
2005
publication date
ofr20051323
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Ludington, Steve
Moring, Barry C.
Miller, Robert J.
Flynn, Kathryn
Hopkins, Melanie J.
Stone, Paul
Bedford, David R.
Haxel, Gordon A.
2005
Preliminary integrated geologic map databases for the United States -
western states: California, Nevada, Arizona, and Washington
Open-File Report
2005-1305
Menlo Park, California
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1305/
500000
digital GIS data files
2005
publication date
ofr20051305
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Nicholson, Suzanne W.
Dicken, Connie L.
Horton, John D.
Labay, Keith A.
Foose, Michael P.
Mueller, Julia A. L.
2005
Preliminary integrated geologic map databases for the United States :
Kentucky, Ohio, Tennessee, and West Virginia
Open-File Report
2005-1324
Reston, Virginia
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1324/
500000
digital GIS data files
2005
publication date
ofr20051324
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Stoeser, Douglas B.
Green, Gregory N.
Morath, Laurie C.
Heran, William D.
Wilson, Anna B.
Moore, David W.
Van Gosen, Bradley S.
2005
Preliminary integrated geologic map databases for the United States :
Central states : Montana, Wyoming, Colorado, New Mexico, Kansas,
Oklahoma, Texas, Missouri, Arkansas, and Louisiana
Open-File Report
2005-1351
Denver, Colorado
U.S. Geological Survey
http://pubs.usgs.gov/of/2005/1351/
500000
digital GIS data files
2005
publication date
ofr20051351
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Nicholson, Suzanne W.
Dicken, Connie L.
Foose, Michael P.
Mueller, Julie
2004
Integrated geologic map databases for the United States; the upper
midwest states: Minnesota, Wisconsin, Michigan, Illinois, and Indiana
Open-File Report
2004-1355
Reston, Virginia
U.S. Geological Survey
http://pubs.usgs.gov/of/2004/1355/
500000
digital GIS data files
2004
publication date
ofr20041355
Geologic units from the USGS state geologic map compilation were included in this data set with minor modification.
Geospatial data from the state-by-state compilations was drawn
from the USGS web sites for the publications containing them. A
few corrections were made, focusing mostly on the lithology, by
adding columns to the feature attribute tables for category terms
from Lithclass version 6.2 for the primary and minor lithology of
each unit. Those values were taken from the existing rocktype1
and rocktype2 fields by choosing the closest term in Lithclass 6.2
for the given value of the rocktype field.
Attribute data from the related tables was combined into XML
documents, one per geologic unit, indexed in a separate database
by the field unit_link, by which those reports are related to the
polygon table.
Data from all of the conterminous US states was inserted into a
consolidated database, with a single table for all of the geologic
unit polygons.
A field for the state was added to the polygon table, and a field
containing a URL to the online description of the geologic unit.
A single shapefile was created using the polygon data with these
abbreviated fields; that shapefile is presented as this data set.
ofr20061272
ofr20051325
ofr20051323
ofr20051305
ofr20051324
ofr20051351
ofr20041355
20110922
Peter N Schweitzer
USGS ER GD
Geologist
mailing address
12201 Sunrise Valley Drive
Reston
VA
20192-0002
USA
703-648-6533
703-648-6252
pschweitzer@usgs.gov
Vector
G-Polygon
319822
decimal degrees
World Geodetic System 1984
WGS 84
6378137
298.257
geol_poly
Geologic units, often aggregated as appropriate for a 1:500,000 scale compilation.
url
Hypertext link to an online report describing the geologic unit, whose
contents are drawn from the complex attribute database provided in the
original state geologic map compilations with some additional geographic
indexing.
Values of the form http://tin.er.usgs.gov/geology/state/sgmc-unit.php?unit=(unit_link) where (unit_link) is the value of the unit_link field in this table.
unit_link
Unique identifier for the geologic unit.
Two-letter state abbreviation concatenated with the map symbol (rewritten as ASCII), a semicolon, and a version number.
source
Unique identifier for the primary reference source defining the unit.
A value like MD001 where the first two letters indicate the state and the three digits give the sequence number for the reference in a list provided in the USGS publication.
unit_age
Description of the geologic age of the unit, typically not strictly
controlled text.
In most cases the text will consist of or contain standard chronostratigraphic age terms such as Devonian or Cretaceous.
lith62
Category term for the primary lithology of the unit
Lithclass 6.2
http://tin.er.usgs.gov/catalog/Lithclass.rdf
lith62mino
Category term for the secondary lithology of the unit
Lithclass 6.2
http://tin.er.usgs.gov/catalog/Lithclass.rdf
state
Two-letter state abbreviation for the polygon.
USPS State Abbreviations
http://zip4.usps.com/ncsc/lookups/usps_abbreviations.html
Peter N Schweitzer
USGS ER GD
Geologist
mailing address
12201 Sunrise Valley Drive
Reston
VA
20192-0002
USA
703-648-6533
703-648-6252
pschweitzer@usgs.gov
USGS SGMC combined units
This report is preliminary and has not been reviewed for
conformity with U.S. Geological Survey editorial standards (or
with the North American Stratigraphic Code). Any use of trade,
product, or firm names is for descriptive purposes only and does
not imply endorsement by the U.S. Government.
Shapefile
1.0
Geologic unit polygons with lithology and a link to description
unzip
523 megabytes
http://tin.er.usgs.gov/geology/state/geol_poly.zip
none
20110922
Peter N Schweitzer
USGS ER GD
Geologist
mailing address
12201 Sunrise Valley Drive
Reston
VA
20192-0002
USA
703-648-6533
703-648-6252
pschweitzer@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998