This database represents an attempt to digitally capture all the geologic information available on the published paper map. Separate coverages are provided for the map unit polygons, linear glacial features, point data for drumlins and type localities, important stratigraphic sections, and line coverages for the hydrology and topography.
The description of map units and sources of information are both included as PDF files.
The published maps of the Quaternary Geologic Atlas of the U.S. used three separate projections. To promote uniformity, the projection of this database was changed from Lambert Conformal Conic to Albers Equal Area and all subsequent digital databases will similarly be changed to Albers Equal Area Projection.
Illustrations are provided showing relationships of the loess distribution and thickness; late Wisconsin glacial lobes, sublobes and advances within lobes and sublobes, and areas of responsibility for the compilation of the map. An illustration is provided showing the correlation of map units.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this Federal Geographic Data Committee- compliant metadata file is intended to document the data set in nonproprietary form, as well as in ARC/INFO format, this metadata file includes some ARC/INFO-specific terminology.
The dataset for the Chicago quadrangle consists of 10 coverages.
geo_net
gla_lin
gla_pnt
hydr_lin
topo_lin
bnd_lin
bnd_net
rd_lin
rr_lin
grid_lin
The dataset also includes an ARC/INFO AML, lineset, shadeset, and
markerset that will produce the EPS file of the geology and glacial
features and the list of map units.
Digitization and attributing of compilation: Digitizing contractor scanned source stable-base material, vectorized scan, attributed files, and produced check plots and coverages. C.A. Bush proofread check plots and reviewed digital files; made final corrections as needed; produced graphical files and imported them into graphics program to prepare plot file; proofread cartographic product; prepared illustrations and word processing files of descriptions of map units and sources of information. The original paper map was scanned and recreated as PDF files. (The original map was thoroughly reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature.)
The geo_net.pat INFO file consists of the following items:
GEOCODE--Refers to the type of polygon and is one of the following: map unit code, "lake", or "island".
AGE--Refers to the age of the map unit and is one of the following: "HOLOCENE", "HOLOCENE AND LATE WISCONSIN", "LATE WISCONSIN", "EARLY WISCONSIN", "WISCONSIN", "ILLINOIAN", "PLEISTOCENE", "QUATERNARY" OR "PRE-QUATERNARY".
MORAINES--A modifier to the map unit indicating that the unit is a moraine and is one of the following: "Ground Moraine", "End Moraine", or "Ground Moraine and end moraine under Lake Michigan."
MAP_UNITS--A description of the soils within the map units (see below).
MODIFIER--Indicates that the map unit is covered with loess more than 2 m thick ("loess mantle") or if the unit is under water ("submerged").
COLOR--An integer value representing a shade pattern in the shadeset color524.shd used in preparing the plotfile of the map.
Items in geo_net.pat are defined as follows:
GEOCODE MAPUNITS, (AGE)
lc LAKE CLAY AND SILT UNDER LAKE MICHIGAN, HOLOCENE
ls LAKE SAND AND GRAVEL UNDER LAKE MICHIGAN, HOLOCENE
al ALLUVIUM, HOLOCENE AND LATE WISCONSIN
hs SWAMP DEPOSIT, HOLOCENE AND LATE WISCONSIN
hp PEAT, HOLOCENE AND LATE WISCONSIN
es EOLIAN SHEET SAND, HOLOCENE AND LATE WISCONSIN
ed DUNE SAND, HOLOCENE AND LATE WISCONSIN
el LOESS, HOLOCENE AND LATE WISCONSIN
ca COLLUVIUM AND SHEETWASH ALLUVIUM, HOLOCENE AND LATE WISCONSIN
lca LAKE CLAY AND SILT, LATE WISCONSIN
lsa LAKE SAND AND GRAVEL, LATE WISCONSIN
gg OUTWASH SAND AND GRAVEL, LATE WISCONSIN
gs OUTWASH SAND, LATE WISCONSIN
kg ICE-CONTACT SAND AND GRAVEL, LATE WISCONSIN
Tills in Wisconsin, Michigan, Indiana, and Ohio
tc CLAYEY TILL--Ground moraine, LATE WISCONSIN
tc CLAYEY TILL--End moraine, LATE WISCONSIN
tca CLAYEY TILL--Ground moraine, LATE WISCONSIN
tca CLAYEY TILL--End moraine, LATE WISCONSIn
tcb CLAYEY TILL--Ground moraine, LATE WISCONSIN
tcb CLAYEY TILL--End moraine, LATE WISCONSIN
tl LOAMY TILL--Ground moraine, LATE WISCONSIN
tl LOAMY TILL--End moraine, LATE WISCONSIN
tlg LOAMY TILL--Ground moraine, LATE WISCONSIN
tlg LOAMY TILL--End moraine, LATE WISCONSIN
td SANDY LOAMY TILL--Ground moraine, LATE WISCONSIN
td SANDY LOAMY TILL--End moraine, LATE WISCONSIN
Till Members of Wedron Formation in Illinois and under
Lake Michigan, and Equivalent Tills in Adjacent Wisconsin
and Indiana
tac CLAYEY TILL (MANITOWOC TILL MEMBER UNDER LAKE MICHIGAN),
LATE WISCONSIN
tad CLAYEY TILL (SHOREWOOD TILL MEMBER UNDER LAKE MICHIGAN),
LATE WISCONSIN
tah CLAYEY TILL (WADSWORTH TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN INDIANA)--Ground moraine, LATE WISCONSIN
tah CLAYEY TILL (WADSWORTH TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN INDIANA)--Ground moraine and end moraine under Lake Michigan,
LATE WISCONSIN
tah CLAYEY TILL (WADSWORTH TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN INDIANA)--End moraine, LATE WISCONSIN
tea SANDY LOAMY TILL (HAEGER TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN WISCONSIN)--Ground moraine, LATE WISCONSIN
tea SANDY LOAMY TILL (HAEGER TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN WISCONSIN)--End moraine, LATE WISCONSIN
taj CLAYEY TILL (YORKVILLE TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN INDIANA)--Ground moraine, LATE WISCONSIN
taj CLAYEY TILL (YORKVILLE TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT
IN INDIANA)--End moraine, LATE WISCONSIN
tan CLAYEY TILL (SNIDER TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT IN
INDIANA)--Ground moraine, LATE WISCONSIN
tan CLAYEY TILL (SNIDER TILL MEMBER IN ILLINOIS AND ITS EQUIVALENT IN
INDIANA)--End moraine, LATE WISCONSIN
tkb LOAMY TILL (BATESTOWN TILL MEMBER, MALDEN TILL MEMBER, AND MALDEN
AND SNIDER TILL MEMBERS UNDIFFERENTIATED IN ILLINOIS; BATESTOWN
TILL MEMBER EQUIVALENT IN INDIANA)--Ground moraine, LATE WISCONSIN
tkb LOAMY TILL (BATESTOWN TILL MEMBER, MALDEN TILL MEMBER, AND MALDEN
AND SNIDER TILL MEMBERS UNDIFFERENTIATED IN ILLINOIS; BATESTOWN
TILL MEMBER EQUIVALENT IN INDIANA)--End moraine, LATE WISCONSIN
tkc LOAMY TILL (PIATT TILL MEMBER)--Ground moraine, LATE WISCONSIN
tkc LOAMY TILL (PIATT TILL MEMBER)--End moraine, LATE WISCONSIN
tkd LOAMY TILL (TISKILWA, DELAVAN, AND FAIRGRANGE TILL MEMBERS IN
ILLINOIS; FAIRGRANGE TILL MEMBER EQUIVALENT IN INDIANA)
--Ground moraine, LATE WISCONSIN
tkd LOAMY TILL (TISKILWA, DELAVAN, AND FAIRGRANGE TILL MEMBERS IN
ILLINOIS; FAIRGRANGE TILL MEMBER EQUIVALENT IN INDIANA)
--End moraine, LATE WISCONSIN
tkj LOAMY TILL (CAPRON TILL MEMBER OF WINNEBAGO FORMATION IN ILLINOIS
AND EQUIVALENT TILL IN WISCONSIN), EARLY WISCONSIN
tej SANDY LOAMY TILL (ARGYLE TILL MEMBER OF WINNEBAGO FORMATION IN
ILLINOIS AND EQUIVALENT TILL IN WISCONSIN)--Ground moraine,
EARLY WISCONSIN
tej SANDY LOAMY TILL (ARGYLE TILL MEMBER OF WINNEBAGO FORMATION IN
ILLINOIS AND EQUIVALENT TILL IN WISCONSIN)--End moraine,
EARLY WISCONSIN
lcd LAKE SILT AND CLAY, WISCONSIN
lci LAKE SILT AND CLAY, ILLINOIAN
lsp LAKE SAND AND SILT, ILLINOIAN
gsi OUTWASH SILT, SAND, AND GRAVEL, ILLINOIAN
kgi ICE-CONTACT SAND AND GRAVEL, ILLINOIAN
tal CLAYEY TILL (RADNOR AND STERLING TILL MEMBERS OF GLASFORD
FORMATION IN ILLINOIS), ILLINOIAN
tag CLAYEY TILL (ESMOND TILL MEMBER OF GLASFORD FORMATION IN ILLINOIS),
ILLINOIAN
tke LOAMY TILL (LEE CENTER TILL MEMBER OF GLASFORD FORMATION IN
ILLINOIS) --Ground moraine, ILLINOIAN
tke LOAMY TILL (LEE CENTER TILL MEMBER OF GLASFORD FORMATION IN
ILLINOIS) --End moraine, ILLINOIAN
tkm LOAMY TILL (OGLE, HULICK, AND VANDALIA TILL MEMBERS OF GLASFORD
FORMATION IN ILLINOIS; OGLE TILL MEMBER EQUIVALENT IN WISCONSIN),
ILLINOIAN
tam CLAYEY TILL (WINSLOW TILL MEMBER OF GLASFORD FORMATION IN ILLINOIS
AND ITS EQUIVALENT IN WISCONSIN)--Ground moraine, ILLINOIAN
tam CLAYEY TILL (WINSLOW TILL MEMBER OF GLASFORD FORMATION IN ILLINOIS
AND ITS EQUIVALENT IN WISCONSIN)--End moraine, ILLINOIAN
cr COLLUVIUM, PLEISTOCENE
cc COLLUVIUM, QUATERNARY
R BEDROCK, PRE-QUATERNARY
f MANMADE
NOTE: All units listed as EARLY WISCONSIN on the original map are
presently recognized as being ILLINOIAN. Unit lcd listed as WISCONSIN
is probably ILLINOIAN and may be the same map unit as lci.
The geo_net.aat INFO file consists of the following item:
LTYPE--Refers to the type of arc and is one of the following:
"contact," "shoreline," or "map boundary."
The gla_lin coverage contains lines of linear glacial features. The gla_lin.aat INFO file consists of the following items: TYPE--Refers to the type of glacial feature described by the arc and is one of the following: "esker," "limit of glacial advance," "buried moraine," "meltwater channel," "shoreline deposits," or "map boundary". MODIFIER--Refers only to ltype = "meltwater channel" and is either "left bank" or "right bank". ACCURACY--Refers to accuracy of location of arcs in the gla_lin coverage and is either "certain" or "inferred". NAME--Refers to the geounit name (taj) of inferred buried end moraine.
The gla_pnt coverage contains points that represent drumlins, places where the direction of ice movement is indicated by striations, or the location of important stratigraphic sections. The gla_pnt.pat INFO file consists of the following items: TYPE--Refers to the type of feature shown at the point and is one of the following: "drumlin," "direction of ice movement," "concentric minor moraines," "glacially fluted landforms," "wind direction," or the name of important stratigraphic sections. ANGLE--Refers to the direction of drumlin or ice movement; in degrees measured clockwise from north. MRKANGLE--Negative of ANGLE; useful for plotting srmbols in ARCPLOT.
Hydr_lin is a line coverage created after scanning the hydrographic layer that was used in the original paper map. It has no attributes.
Topo_lin is a line coverage created after scanning the topographic layer that was used in the original paper map. It has no attributes.
Bnd_lin is a line coverage created from 1:2,000,000-scale U.S. Geological Survey Digital Line Graph coverages (DLG). It contains lines representing state boundaries. The bnd_lin.aat INFO file contains the following item: LTYPE--Refers to the type of line and contains the values: "state boundary", or "map boundary". The coverage is annotated with state names along boundaries.
Bnd_net is a polygon coverage created from 1:2,000,000-scale DLG coverages and contains political and administrative boundaries. Polygons are attributed in the standard DLG coding scheme and the Federal Information Processing Standards (FIPS).
Rd_lin is a line coverage created from 1:2,000,000-scale DLG coverages. The coverage contains lines representing roads in the map area. All DLG attributes have been stripped from the lines except ROUTE_NUMBER1, ROUTE_NUMBER2, ROUTE_NUMBER3, and ROUTE_NUMBER4.
Rr_lin is a line coverage created from 1:2,000,000-scale DLG coverages. The coverage contains lines representing railroads in the map area. It has no DLG attributes.
Grid_lin is a line coverage created to display projection lines in one degree increments. It has no attributes.
U.S. Department of the Interior
U.S. Geological Survey
This page is <URL: https://pubs.usgs.gov/imap/1983/i-1420/nk-16/>
Maintained
by: Tracy Roudebush / troudebush@usgs.gov
Last Modified Tuesday, 08-October-2002
Generated by mp version 2.4.35 on Fri Aug 02 10:42:47 2002