Preliminary bedrock geology of Dane County, Wisconsin: Geologic Map Units (2013; 1:100,000 scale)

Shapefile

Thumbnail

Tags
geoscientificInformation, bedrock geology, Dane County, Wisconsin


Summary

This vector dataset is a part of the digital version of the map titled Preliminary bedrock geology of Dane County, Wisconsin, by B.A. Brown, K. Massie-Ferch, and R.M. Peters (Open-File Report 2013-01). The map and cross sections are based on fieldwork and analysis of subsurface data by the authors between 1995 and 1996, and on earlier field mapping by P.G. Olcott (1972). As a set, they depict basic information about the composition, distribution, and thickness of bedrock formations that are exposed at the land surface or are penetrated in the subsurface by municipal wells, domestic water wells, and engineering test borings. They are intended to provide the basic geologic framework required for groundwater and mineral resource analysis, and land-use planning. Understanding the nature of the bedrock is important for both environmental and economic reasons.

Description

These polygon features represent bedrock geologic units in Dane County, Wisconsin. The map data are a regional interpretation of the geology, intended for presentation at a scale of 1:100,000, and may not be sufficient for site-specific applications.

Credits

Unpublished field maps, notes, and geologic compilation work done by P.G. Olcott from 1970 to 1972 provided an invaluable resource throughout this project. The authors also acknowledge the early contributions to mapping in southwestern Dane County, and regional geophysical analysis provided by M.G. Mudrey, Jr, and cartographic work done by M.L. Czechanski; and digitization of outcrops by A.M.K. Fritz (1995). Cartography and GIS data analysis for WOFR2013-01 were provided by K.C. Roushar and P.R. Schoephoester.

Use limitations

These data are available to anyone; however, the data are copyrighted and are licensed for use, not sold. These data represent work performed by the Wisconsin Geological and Natural History Survey and are released to the open files in the interest of making the information readily available. The data have not been extensively reviewed for conformity with the Wisconsin Geological and Natural History Survey standards and nomenclature. This dataset was developed from data of varying map scales and may not be accurate for site-specific applications.

THESE DATA ARE PROVIDED BY THE WISCONSIN GEOLOGICAL AND NATURAL HISTORY SURVEY (WGNHS) ON AN "AS IS" BASIS. WGNHS WILL NOT BE LIABLE FOR ANY DAMAGES OF ANY KIND ARISING FROM THE USE OF THESE DATA, INCLUDING, BUT NOT LIMITED TO DIRECT, INDIRECT, PUNITIVE, AND CONSEQUENTIAL. WGNHS MAKES NO WARRANTIES ON THESE DATA, EXPRESS, IMPLIED, STATUTORY, OR IN ANY OTHER PROVISION OF ANY AGREEMENT OR COMMUNICATION, AND SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Extent

West -89.839550   East -89.006335
North 43.295661   South 42.842500

Scale Range
Maximum (zoomed in) 1:50,000
Minimum (zoomed out) 1:500,000

ArcGIS Metadata 

Topics and Keywords 

Themes or categories of the resource  geoscientificInformation


*Content type  Downloadable Data
Export to FGDC CSDGM XML format as Resource Description No

Place keywords  Dane County

Place keywords  Wisconsin

Theme keywords  bedrock geology

Citation 

Title Preliminary bedrock geology of Dane County, Wisconsin: Geologic Map Units (2013; 1:100,000 scale)
Publication date 2013-08-06 00:00:00


Edition 1.0


Presentation formats  digital map
FGDC geospatial presentation format  vector digital data


Series
Name Open-File Report
Issue 2013-01

Collection title Preliminary bedrock geology of Dane County, Wisconsin: Open-File Report 2013-01


Other citation details Suggested citation: Brown, B.A., Massie-Ferch, K., and Peters, R.M., 2013, Preliminary Bedrock Geology of Dane County, Wisconsin: Wisconsin Geological and Natural History Survey Open-File Report 2013-01, 2 pls., scale 1:100,000.


Citation Contacts 

Responsible party
Organization's name Wisconsin Geological and Natural History Survey (WGNHS)
Contact's role  publisher


Contact information
Phone
Voice 608-262-1705
Voice Wisconsin Relay: 711

Address
Type
Delivery point 3817 Mineral Point Road , Madison, WI, 53705, US

Online resource
Location www.WisconsinGeologicalSurvey.org



Responsible party
Organization's name Wisconsin Geological and Natural History Survey (WGNHS)
Contact's role  originator


Resource Details 

Dataset languages  English (UNITED STATES)
Dataset character set  utf8 - 8 bit UCS Transfer Format


Status  completed
Spatial representation type  vector


Supplemental information
The geologic map (Plate 1) illustrates the distribution of geologic formations at the bedrock surface. The cross sections (Plate 2) depict the thickness and configuration of these formations down to the crystalline basement, and the thickness of overlying Quaternary deposits. The map and sections are based on fieldwork and analysis of subsurface data by the authors from 1995 to 1996, and on earlier field mapping by P.G. Olcott (1972). Subsurface data included WGNHS geologic logs, WDNR well construction reports, and engineering borings. Well locations, outcrop locations, and other geologic control points are shown on Plate 1. 

These data represent work performed by the Wisconsin Geological and Natural History Survey and are released to the open files in the interest of making the information readily available. The data have not been extensively reviewed for conformity with the Wisconsin Geological and Natural History Survey standards and nomenclature.
*Processing environment Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.1.1.3143


Credits
Unpublished field maps, notes, and geologic compilation work done by P.G. Olcott from 1970 to 1972 provided an invaluable resource throughout this project. The authors also acknowledge the early contributions to mapping in southwestern Dane County, and regional geophysical analysis provided by M.G. Mudrey, Jr, and cartographic work done by M.L. Czechanski; and digitization of outcrops by A.M.K. Fritz (1995). Cartography and GIS data analysis for WOFR2013-01 were provided by K.C. Roushar and P.R. Schoephoester.
ArcGIS item properties
*Name dn_bg_GeologyUnits_o201301
*Size 5.413
Locationhttp://WisconsinGeologicalSurvey.org/
Access protocol Network

Extents 

Extent
Geographic extent
Bounding rectangle
West longitude -89.83955
East longitude -89.006335
South latitude 42.8425
North latitude 43.295661

Extent
Geographic extent
Bounding rectangle
Extent type  Extent used for searching
*West longitude -89.839550
*East longitude -89.006335
*North latitude 43.295661
*South latitude 42.842500
*Extent contains the resource Yes

Extent in the item's coordinate system
*West longitude 533110.475000
*East longitude 600608.370625
*South latitude 263796.796875
*North latitude 313660.951125
*Extent contains the resource Yes

Resource Points of Contact 

Point of contact
Organization's name Wisconsin Geological and Natural History Survey
Contact's position Information Manager
Contact's role  point of contact


Contact information
Phone
Voice (608) 262-1705
Voice Wisconsin Relay: 711

Address
Type both
Delivery point 3817 Mineral Point Road
City Madison
Administrative area WI
Postal code 53705-5100
Country US
e-mail addressgis@wgnhs.uwex.edu



Resource Maintenance 

Resource maintenance
Update frequency  unknown


Resource Constraints 

Legal constraints
Limitations of use
See access and use constraints information.
Constraints
Limitations of use
These data are available to anyone; however, the data are copyrighted and are licensed for use, not sold. These data represent work performed by the Wisconsin Geological and Natural History Survey and are released to the open files in the interest of making the information readily available. The data have not been extensively reviewed for conformity with the Wisconsin Geological and Natural History Survey standards and nomenclature. This dataset was developed from data of varying map scales and may not be accurate for site-specific applications. THESE DATA ARE PROVIDED BY THE WISCONSIN GEOLOGICAL AND NATURAL HISTORY SURVEY (WGNHS) ON AN "AS IS" BASIS. WGNHS WILL NOT BE LIABLE FOR ANY DAMAGES OF ANY KIND ARISING FROM THE USE OF THESE DATA, INCLUDING, BUT NOT LIMITED TO DIRECT, INDIRECT, PUNITIVE, AND CONSEQUENTIAL. WGNHS MAKES NO WARRANTIES ON THESE DATA, EXPRESS, IMPLIED, STATUTORY, OR IN ANY OTHER PROVISION OF ANY AGREEMENT OR COMMUNICATION, AND SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Spatial Reference 

ArcGIS coordinate system
*Type Projected
*Geographic coordinate reference GCS_North_American_1983_HARN
*Projection NAD_1983_HARN_Wisconsin_TM
*Coordinate reference details
Projected coordinate system
Well-known identifier 3071
X origin -5100900
Y origin -14478100
XY scale 450445547.3910538
Z origin -100000
Z scale 10000
M origin -100000
M scale 10000
XY tolerance 0.001
Z tolerance 0.001
M tolerance 0.001
High precision true
Latest well-known identifier 3071
Well-known text PROJCS["NAD_1983_HARN_Wisconsin_TM",GEOGCS["GCS_North_American_1983_HARN",DATUM["D_North_American_1983_HARN",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",520000.0],PARAMETER["False_Northing",-4480000.0],PARAMETER["Central_Meridian",-90.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0],AUTHORITY["EPSG",3071]]

Reference system identifier
*Value 3071
*Codespace EPSG
*Version 7.11.2


Spatial Data Properties 

Vector
*Level of topology for this dataset  geometry only


Geometric objects
Feature class name dn_bg_GeologyUnits_o201301
*Object type  composite
*Object count 700



ArcGIS Feature Class Properties
Feature class name dn_bg_GeologyUnits_o201301
*Feature type Simple
*Geometry type Polygon
*Has topology FALSE
*Feature count 700
*Spatial index FALSE
*Linear referencing FALSE



Lineage 

Lineage statement
The dataset was developed from sources of varying map scales and time periods. Initial data capture was in ArcInfo coverage format, subsequently imported to ArcGIS geodatabase format (WTM83 HARN), and exported to shapefiles for distribution.

Distribution 

Distributor
Contact information
Organization's name Wisconsin Geological and Natural History Survey
Contact's position Map and Publication Sales
Contact's role  distributor


Contact information
Phone
Voice (608) 263-7389
Fax (608) 262-8086
Voice Wisconsin Relay: 711

Address
Type both
Delivery point 3817 Mineral Point Road
City Madison
Administrative area WI
Postal code 53705-5100
Country US
e-mail addressmapsales@uwex.edu

Hours of service 8:00 am-4:30 pm M-F (CST)


Transfer options
Online source
Locationhttp://WisconsinGeologicalSurvey.org/
Description  Preliminary bedrock geology of Dane County, Wisconsin: Open-File Report 2013-01



Distribution format
Name Shapefile
Version ArcGIS 10.1


Fields 

Details for object dn_bg_GeologyUnits_o201301 
*Type Feature Class
*Row count 700
Definition
Dane County, geologic map units, WGNHS Open-File Report 2013-01
Definition source
WGNHS


Field FID
 
*Alias FID
*Data type OID
*Width 4
*Precision 0
*Scale 0
*Field description
Internal feature number.
*Description source
Esri
*Description of values Sequential unique whole numbers that are automatically generated.




Field SHAPE
 
*Alias Shape
*Data type Geometry
*Width 0
*Precision 0
*Scale 0
*Field description
Feature geometry.
Description source
Esri
*Description of values Coordinates defining the features.




Field UnitCode
 
*Alias UnitCode
*Data type String
*Width 25
*Precision 0
*Scale 0
Field description
Geologic map unit identifier.
Description source
WGNHS
List of values
Value Om
Description Maquoketa Formation. Dolomitic shale and shaly dolomite, gray to very dark gray. No complete section of the formation is known in Dane County; an eroded section caps East Blue Mound and it has been tentatively identified in an isolated area of complex faulting southeast of Madison. A complete 240-foot (73 m) section is preserved on West Blue Mound in adjacent Iowa County. The formation does not outcrop at the surface because of deep weathering.
Enumerated domain value definition source WGNHS


Value Os
Description Sinnipee Group. Three formations make up the Sinnipee group: Galena, Decorah, and Platteville. They are described separately because they are easily distinguishable in outcrops and in subsurface samples such as core and drill cuttings, but the limited exposures and the thin Decorah interval makes mapping three rock units impractical at this map scale. Galena Formation: Dolomite and cherty dolomite. Massive medium-bedded crystalline dolomite with distinctive mottled weathering pattern. Yellow-brown to buff, except for the lower 20 feet (6 m) which are more shaly and light gray. Discontinuous beds of nodular chert are common. The Galena Formation reaches a known maximum thickness of 220 feet (67 m) in west-central Dane County. Decorah Formation: Shaly dolomite. The Decorah reaches a maximum thickness of 10 feet (3 m) in west-central Dane County. Platteville Formation: Dolomite and shaly dolomite, gray to buff, fine to medium texture. Gray weathering is typical of shaly intervals. Pure carbonate units are thick to medium bedded. Shaly units typically have thin, wavy to nodular bedding. Minor white chert is present in discontinuous isolated beds. In Dane County, the maximum thickness of the formation is approximately 80 feet (24 m).
Enumerated domain value definition source WGNHS


Value Oa
Description Ancell Group. The Ancell Group is not divided on the map, but the following formations and members can be recognized in outcrops and in the subsurface. Glenwood Formation: Sandstone, siltstone, and/or shale; yellow-brown to green; discontinuous and variable in lithology, texture, and thickness. Commonly 1 to 2 feet (0.3 to 0.6 m) thick in outcrops, but reported as thicker in the subsurface. St. Peter Formation: Subdivided into an upper mature quartz sandstone (Tonti Member) and a basal shale (Readstown Member). Occupies channels eroded in the underlying rocks; varies widely in thickness across Dane County, from absent to greater than 200 feet (61 m). Members are not mapped separately. Tonti Member: Consists of poorly cemented, clean, medium-grained quartz sandstone with typical well-rounded and frosted grains; commonly cross-bedded. Light buff to white on fresh surfaces except where cemented by iron oxide; often case hardens to brownish gray. Forms steep cliffs and ledges. Readstown Member: Red brown to purple to green shale and shaly sandstone. May contain clasts of chert and blocks of dolomite derived from weathering of the underlying Prairie du Chien Group. Easily eroded and generally not exposed at the surface.
Enumerated domain value definition source WGNHS


Value Op
Description Prairie du Chien Group. Consists of the Shakopee Formation and Oneota Formation which are not separated at this map scale. The Prairie du Chien is composed of massive- to medium-bedded dolomite that is light brown to gray in color. The New Richmond Member, a sandstone forming the bottom part of the Shakopee, is thin to absent in Dane County. The Prairie du Chien is vuggy, sandy, and oolitic; orange to pink to gray nodular chert is common. It forms bluffs and caps ridges in northwestern Dane County. It varies in thickness from 145 feet (44 m) in eastern Dane County to 220 feet (67 m) in western Dane County. In central Dane County, Prairie du Chien rocks have been entirely removed by erosion.
Enumerated domain value definition source WGNHS


ValueCt
Description Trempealeau Group. Quartz sandstone, dolomitic siltstone, silty dolomite, and sandy dolomite. Consists of two formations which were combined as one mapping unit. The Jordan Formation, a white to yellow-brown quartz sandstone, overlies the St. Lawrence Formation, a silty dolomite to dolomitic siltstone. The Jordan Formation can be divided into an upper, coarse-grained Van Oser Member, and the lower, fine-grained Norwalk Member. The St. Lawrence Formation can be divided into the Lodi Member, a dolomitic siltstone, and the Black Earth Member, a silty dolomite with a trace of silt-sized glauconite. The Trempealeau Group is about 75 feet (23 m) thick where not eroded.
Enumerated domain value definition source WGNHS


ValueCtc
Description Tunnel City Group. Medium to very fine-grained quartz sandstone, locally very glauconitic. Two formations have been defined in outcrop and subsurface based on distinct textural differences, but are not mapped separately. The Lone Rock Formation consists of very fine shaly and glauconitic, feldspathic sandstone, thin bedded and commonly green where highly glauconitic. The Mazomanie Formation is more massive, fine to medium grained, and not glauconitic. The Tunnel City Group commonly forms vegetated slopes. Maximum thickness in Dane County is about 150 feet (46 m).
Enumerated domain value definition source WGNHS


ValueCw
Description Wonewoc Formation. Quartz sandstone, medium grained, brownish yellow to white, with medium- to large-scale cross bedding commonly seen in outcrop. Reaches a maximum thickness of 165 feet (50 m) in the subsurface. Exposed in outcrop in northwestern Dane County along the Wisconsin River valley. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated domain value definition source WGNHS


ValueCec
Description Eau Claire Formation. Fine to very fine, silty, shaly, and/or dolomitic quartz sandstone. It is shown schematically as rimming the Madison lakes, but is nowhere exposed above water. Thickness varies from absent in northern Dane County to about 80 feet (24 m) in western Dane County. Dolomitic medium- to coarse-sandstone layers, formerly assigned to the Eau Claire Formation, have been reassigned to the Mount Simon Formation; these layers are primarily found in the Madison area. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated domain value definition source WGNHS


ValueCms
Description Mount Simon Formation. Primarily medium- to coarse-grained quartz sandstone, with a pebble conglomerate near the basal contact with the Precambrian. Generally cemented by carbonate, iron oxide, and locally by silica. Shaly layers present. The upper part may be locally dolomitic, especially in the Madison area, and may grade gradually upward into the overlying Eau Claire Formation. Thickness in Dane County ranges from about 300 feet (90 m) to over 600 feet (180 m). Like the overlying Eau Claire Formation, the Mount Simon is shown schematically as lining the bottoms of a greater portion of the Madison lakes. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated domain value definition source WGNHS




Field SHAPE_Leng
 
*Alias SHAPE_Leng
*Data type Double
*Width 19
*Precision 0
*Scale 0




Field SHAPE_Area
 
*Alias SHAPE_Area
*Data type Double
*Width 19
*Precision 0
*Scale 0
*Field description
Area of feature in internal units squared.
Description source
Esri
*Description of values Positive real numbers that are automatically generated.




Field UnitID
 
*Alias UnitID
*Data type String
*Width 25
*Precision 0
*Scale 0
Field description
Map label coded for Geologic Age Font.
Description source
WGNHS
List of values
Value Om
Description Maquoketa Formation
Enumerated domain value definition source WGNHS


Value Os
Description Sinnipee Group
Enumerated domain value definition source WGNHS


Value Oa
Description Ancell Group
Enumerated domain value definition source WGNHS


Value Op
Description Prairie du Chien Group
Enumerated domain value definition source WGNHS


Value _t
Description Trempealeau Group
Enumerated domain value definition source WGNHS


Value _tc
Description Tunnel City Group
Enumerated domain value definition source WGNHS


Value _w
Description Wonewoc Formation
Enumerated domain value definition source WGNHS


Value _ec
Description Eau Claire Formation
Enumerated domain value definition source WGNHS


Value _ms
Description Mount Simon Formation
Enumerated domain value definition source WGNHS




Field Name
 
*Alias Name
*Data type String
*Width 254
*Precision 0
*Scale 0
Field description
Map unit name.
Description source
WGNHS
Description of values Unit name for NCGMP format.




Field Desc_
 
*Alias Desc_
*Data type String
*Width 254
*Precision 0
*Scale 0
Field description
Description. Abbreviated explanation from WOFR2013-01
Description source
WGNHS


Field AgeDisplay
 
*Alias AgeDisplay
*Data type String
*Width 128
*Precision 0
*Scale 0
Field description
Geologic age description of mapped units (for Dane County, Ordovician or Cambrian periods).
Description source
WGNHS




Metadata Details 

Metadata language English (UNITED STATES)
Metadata character set  utf8 - 8 bit UCS Transfer Format


Scope of the data described by the metadata  dataset
Scope name* dataset


Last update 2013-08-06


ArcGIS metadata properties
Metadata format ArcGIS 1.0
Metadata style FGDC CSDGM Metadata
Standard or profile used to edit metadata FGDC


Created in ArcGIS for the item 2012-05-24 14:02:48
Last modified in ArcGIS for the item 2013-08-06 14:36:56


Automatic updates
Have been performed Yes
Last update 2013-08-06 13:38:28


Metadata Contacts 

Metadata contact
Organization's name Wisconsin Geological and Natural History Survey
Contact's position Information Manager
Contact's role  point of contact


Contact information
Phone
Voice (608) 262-1705
Voice Wisconsin Relay: 711

Address
Type both
Delivery point 3817 Mineral Point Road
City Madison
Administrative area WI
Postal code 53705-5100
Country US
e-mail addressgis@wgnhs.uwex.edu



Metadata Maintenance 

Maintenance
Update frequency  unknown


Thumbnail and Enclosures 

Thumbnail
Thumbnail type  JPG

FGDC Metadata (read-only) 

Entities and Attributes 

Detailed Description
Entity Type
Entity Type Labeldn_bg_GeologyUnits_o201301
Entity Type Definition
Dane County, geologic map units, WGNHS Open-File Report 2013-01
Entity Type Definition SourceWGNHS

Attribute
Attribute LabelFID
Attribute Definition
Internal feature number.
Attribute Definition SourceEsri
Attribute Domain Values
Unrepresentable Domain
Sequential unique whole numbers that are automatically generated.

Attribute
Attribute LabelSHAPE
Attribute Definition
Feature geometry.
Attribute Definition SourceEsri
Attribute Domain Values
Unrepresentable Domain
Coordinates defining the features.

Attribute
Attribute LabelUnitCode
Attribute Definition
Geologic map unit identifier.
Attribute Definition SourceWGNHS
Attribute Domain Values
Enumerated Domain
Enumerated Domain ValueOm
Enumerated Domain Value Definition
Maquoketa Formation. Dolomitic shale and shaly dolomite, gray to very dark gray. No complete section of the formation is known in Dane County; an eroded section caps East Blue Mound and it has been tentatively identified in an isolated area of complex faulting southeast of Madison. A complete 240-foot (73 m) section is preserved on West Blue Mound in adjacent Iowa County. The formation does not outcrop at the surface because of deep weathering.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOs
Enumerated Domain Value Definition
Sinnipee Group. Three formations make up the Sinnipee group: Galena, Decorah, and Platteville. They are described separately because they are easily distinguishable in outcrops and in subsurface samples such as core and drill cuttings, but the limited exposures and the thin Decorah interval makes mapping three rock units impractical at this map scale. Galena Formation: Dolomite and cherty dolomite. Massive medium-bedded crystalline dolomite with distinctive mottled weathering pattern. Yellow-brown to buff, except for the lower 20 feet (6 m) which are more shaly and light gray. Discontinuous beds of nodular chert are common. The Galena Formation reaches a known maximum thickness of 220 feet (67 m) in west-central Dane County. Decorah Formation: Shaly dolomite. The Decorah reaches a maximum thickness of 10 feet (3 m) in west-central Dane County. Platteville Formation: Dolomite and shaly dolomite, gray to buff, fine to medium texture. Gray weathering is typical of shaly intervals. Pure carbonate units are thick to medium bedded. Shaly units typically have thin, wavy to nodular bedding. Minor white chert is present in discontinuous isolated beds. In Dane County, the maximum thickness of the formation is approximately 80 feet (24 m).
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOa
Enumerated Domain Value Definition
Ancell Group. The Ancell Group is not divided on the map, but the following formations and members can be recognized in outcrops and in the subsurface. Glenwood Formation: Sandstone, siltstone, and/or shale; yellow-brown to green; discontinuous and variable in lithology, texture, and thickness. Commonly 1 to 2 feet (0.3 to 0.6 m) thick in outcrops, but reported as thicker in the subsurface. St. Peter Formation: Subdivided into an upper mature quartz sandstone (Tonti Member) and a basal shale (Readstown Member). Occupies channels eroded in the underlying rocks; varies widely in thickness across Dane County, from absent to greater than 200 feet (61 m). Members are not mapped separately. Tonti Member: Consists of poorly cemented, clean, medium-grained quartz sandstone with typical well-rounded and frosted grains; commonly cross-bedded. Light buff to white on fresh surfaces except where cemented by iron oxide; often case hardens to brownish gray. Forms steep cliffs and ledges. Readstown Member: Red brown to purple to green shale and shaly sandstone. May contain clasts of chert and blocks of dolomite derived from weathering of the underlying Prairie du Chien Group. Easily eroded and generally not exposed at the surface.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOp
Enumerated Domain Value Definition
Prairie du Chien Group. Consists of the Shakopee Formation and Oneota Formation which are not separated at this map scale. The Prairie du Chien is composed of massive- to medium-bedded dolomite that is light brown to gray in color. The New Richmond Member, a sandstone forming the bottom part of the Shakopee, is thin to absent in Dane County. The Prairie du Chien is vuggy, sandy, and oolitic; orange to pink to gray nodular chert is common. It forms bluffs and caps ridges in northwestern Dane County. It varies in thickness from 145 feet (44 m) in eastern Dane County to 220 feet (67 m) in western Dane County. In central Dane County, Prairie du Chien rocks have been entirely removed by erosion.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueCt
Enumerated Domain Value Definition
Trempealeau Group. Quartz sandstone, dolomitic siltstone, silty dolomite, and sandy dolomite. Consists of two formations which were combined as one mapping unit. The Jordan Formation, a white to yellow-brown quartz sandstone, overlies the St. Lawrence Formation, a silty dolomite to dolomitic siltstone. The Jordan Formation can be divided into an upper, coarse-grained Van Oser Member, and the lower, fine-grained Norwalk Member. The St. Lawrence Formation can be divided into the Lodi Member, a dolomitic siltstone, and the Black Earth Member, a silty dolomite with a trace of silt-sized glauconite. The Trempealeau Group is about 75 feet (23 m) thick where not eroded.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueCtc
Enumerated Domain Value Definition
Tunnel City Group. Medium to very fine-grained quartz sandstone, locally very glauconitic. Two formations have been defined in outcrop and subsurface based on distinct textural differences, but are not mapped separately. The Lone Rock Formation consists of very fine shaly and glauconitic, feldspathic sandstone, thin bedded and commonly green where highly glauconitic. The Mazomanie Formation is more massive, fine to medium grained, and not glauconitic. The Tunnel City Group commonly forms vegetated slopes. Maximum thickness in Dane County is about 150 feet (46 m).
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueCw
Enumerated Domain Value Definition
Wonewoc Formation. Quartz sandstone, medium grained, brownish yellow to white, with medium- to large-scale cross bedding commonly seen in outcrop. Reaches a maximum thickness of 165 feet (50 m) in the subsurface. Exposed in outcrop in northwestern Dane County along the Wisconsin River valley. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueCec
Enumerated Domain Value Definition
Eau Claire Formation. Fine to very fine, silty, shaly, and/or dolomitic quartz sandstone. It is shown schematically as rimming the Madison lakes, but is nowhere exposed above water. Thickness varies from absent in northern Dane County to about 80 feet (24 m) in western Dane County. Dolomitic medium- to coarse-sandstone layers, formerly assigned to the Eau Claire Formation, have been reassigned to the Mount Simon Formation; these layers are primarily found in the Madison area. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueCms
Enumerated Domain Value Definition
Mount Simon Formation. Primarily medium- to coarse-grained quartz sandstone, with a pebble conglomerate near the basal contact with the Precambrian. Generally cemented by carbonate, iron oxide, and locally by silica. Shaly layers present. The upper part may be locally dolomitic, especially in the Madison area, and may grade gradually upward into the overlying Eau Claire Formation. Thickness in Dane County ranges from about 300 feet (90 m) to over 600 feet (180 m). Like the overlying Eau Claire Formation, the Mount Simon is shown schematically as lining the bottoms of a greater portion of the Madison lakes. Part of the Elk Mound Group which consists of the Wonewoc Formation, Eau Claire Formation, and Mount Simon Formation. Except for limited exposure of Wonewoc Formation sandstone, the Elk Mound Group is known only in the subsurface in Dane County.
Enumerated Domain Value Definition Source
WGNHS

Attribute
Attribute LabelSHAPE_Leng

Attribute
Attribute LabelSHAPE_Area
Attribute Definition
Area of feature in internal units squared.
Attribute Definition SourceEsri
Attribute Domain Values
Unrepresentable Domain
Positive real numbers that are automatically generated.

Attribute
Attribute LabelUnitID
Attribute Definition
Map label coded for Geologic Age Font.
Attribute Definition SourceWGNHS
Attribute Domain Values
Enumerated Domain
Enumerated Domain ValueOm
Enumerated Domain Value Definition
Maquoketa Formation
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOs
Enumerated Domain Value Definition
Sinnipee Group
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOa
Enumerated Domain Value Definition
Ancell Group
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain ValueOp
Enumerated Domain Value Definition
Prairie du Chien Group
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain Value_t
Enumerated Domain Value Definition
Trempealeau Group
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain Value_tc
Enumerated Domain Value Definition
Tunnel City Group
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain Value_w
Enumerated Domain Value Definition
Wonewoc Formation
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain Value_ec
Enumerated Domain Value Definition
Eau Claire Formation
Enumerated Domain Value Definition Source
WGNHS
Enumerated Domain
Enumerated Domain Value_ms
Enumerated Domain Value Definition
Mount Simon Formation
Enumerated Domain Value Definition Source
WGNHS

Attribute
Attribute LabelName
Attribute Definition
Map unit name.
Attribute Definition SourceWGNHS
Attribute Domain Values
Unrepresentable Domain
Unit name for NCGMP format.

Attribute
Attribute LabelDesc_
Attribute Definition
Description. Abbreviated explanation from WOFR2013-01
Attribute Definition SourceWGNHS

Attribute
Attribute LabelAgeDisplay
Attribute Definition
Geologic age description of mapped units (for Dane County, Ordovician or Cambrian periods).
Attribute Definition SourceWGNHS