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The Upper Midwest States: Minnesota, Wisconsin, Michigan, Illinois and Indiana - The State of Michigan

Frequently anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
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• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?

   Nicholson, Suzanne W., Dicken, Connie L., Foose, Michael P., and Mueller, Julia A.L., 2004, The Upper Midwest States: Minnesota, Wisconsin, Michigan, Illinois and Indiana - The State of Michigan: U.S. Geological Survey Open-File Report 2004-1355, U.S. Geological Survey, Reston, VA.

   Online Links:

   • <http://pubs.usgs.gov/of/2004/1355/>

   This is part of the following larger work.

   Nicholson, Suzanne W., Dicken, Connie L., Foose, Michael P., and Mueller, Julia A.L., 2004, Integrated geologic map databases for the United States: The Upper Midwest States: Minnesota, Wisconsin, Michigan, Illinois and Indiana: U.S. Geological Survey Open-File Report 2004-1355, U.S. Geological Survey, Reston, VA.

   Online Links:

   • <http://pubs.usgs.gov/of/2004/1355/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -91.054582

   East_Bounding_Coordinate: -81.020915

   North_Bounding_Coordinate: 48.435645

   South_Bounding_Coordinate: 41.205085

3. What does it look like?

4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 2004

   Currentness_Reference: publication date

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: map

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Vector data set.

   2. What coordinate system is used to represent geographic features?

      The map projection used is Lambert Conformal Conic.

      Projection parameters:

      Standard_Parallel: 33

      Standard_Parallel: 45

      Longitude_of_Central_Meridian: -100.0

      Latitude_of_Projection_Origin: 0

      False_Easting: 0.00000

      False_Northing: 0.00000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.01
      Ordinates (y-coordinates) are specified to the nearest 0.01
      Planar coordinates are specified in Meters

      The horizontal datum used is North American Datum of 1927.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.4.
      The flattening of the ellipsoid used is 1/294.98.
      

7. How does the data set describe geographic features?

   mi_geol.pat

   Polygon attribute table for the Michigan geologic coverage. (Source: ESRI)

   orig_label

   unmodified map unit symbol from source cover.

   type: character width: 12 output width: 12 (Source: Doug Stoeser)

   Value	Definition
   Agn	Migmatitic gneiss and amphibolite (Late to Early Archean)
   Cm	Munising Formation
   Ct	Trempealeau Formation
   DMs	Sunbury Shale
   Da	Antrim Shale
   Db	Berea Sandstone
   Dbb	Bois Blanc Formation
   Dbd	Bedford Shale
   Dbe	Bell Shale
   Dd	Dundee Limestone
   Ddr	Detroit River Group
   De	Ellsworth Shale
   Dg	Garden Island Formation
   Dm	Mackinac Breccia
   Ds	Sylvania Sandstone
   Dt	Traverse Group
   Jr	Red beds
   Mb	Bayport Limestone
   Mc	Coldwater Shale
   Mm	Marshall Sandstone
   Mmi	Michigan Formation
   Ob	Big Hill Dolomite
   Obr	Black River Limestone
   Oc	Collingwood Limestone
   Op	Prairie du Chien Group
   Oq	Queenston Shale
   Os	Stonington Formation
   Ot	Trenton Limestone
   Ou	Utica Shale
   Pg	Grand River Formation
   Ps	Saginaw Formation
   Pu	Paleozoic undivided
   Sb	Bass Island Dolomite
   Sbb	Burnt Bluff Formation
   Sc	Cataract Formation
   Se	Engadine Dolomite
   Sm	Manistique Formation
   Sp	Point Aux Chenes Shale
   Ss	Salina Group
   Sst	Sainte Ignace Dolomite
   Wd	Dickinson Group, undivided (Late Archean)
   Wga	Gneiss and amphibolite (Late Archean, 2.640-2.750 Ma)
   Wgw	Metagraywacke (Late Archean)
   Wp	Puritan Quartz Monzonite (Late Archean)
   Ws	Biotite schist (Lake Archean)
   Wv	Metabasalt (Late Archean)
   Xam	Unexposed magnetic unit
   Xb	Badwater Greenstone
   Xbc	Blair Creek Formation
   Xc	Copps Formation
   Xch	Chocolay Group, undivided
   Xdvg	Dacite and volcanogenic graywacke
   Xe	Emperor Volcanic Complex
   Xgat	Athelstane Quartz Monzonite
   Xgm	Granitic rocks
   Xh	Hemlock Formation
   Xi	Ironwood Iron-formation
   Xm	Michigamme Formation, undivided
   Xmd	metadiabase
   Xmg	Metagabbro
   Xmi	Mafic metavolcanic rocks
   Xmmc	Menominee and Chocolay Groups, undivided
   Xmn	Negaunee Iron-formation
   Xms	Gray to black slate [of the Michigamme Formation]
   Xmsa	Composite unit of Siamo Slate and Ajibik Quartzite [of the Menominee Group]
   Xmu	Menominee Group, undivided
   Xmvl	Mafic to intermediate flows and pyroclastic rocks [in Michigamme Formation] including Clarksburg Volcanics member
   Xpi	Lower part of Paint River Group
   Xpp	Peavy Pond complex
   Xpu	Upper part of Paint River Group
   Xrhd	Rhyolite to dacite
   Xt	Tyler Formation
   Xvs	Volcanic-sedimentary unit [in the Baraga Group]
   Yc	Copper Harbor Conglomerate
   Ycl	Volcanic member of the Copper Harbor Conglomerate
   Yf	Freda Sandstone
   Yfc	Conglomerate member of Freda Sandstone
   Ygb	Gabbroic rocks of Keweenawan affinity
   Ygr	Granite associated with the Mellen complex
   Yj	Jacobsville Sandstone
   Yk	Kallander Creek Volcanics
   Ykr	Upper rhyolite member of the Kallander Creek Volcanics
   Yn	Nonesuch Shale
   Yplr	Rhyolite at Bergland in the Portage Lake Volcanics
   Yplv	Portage Lake Volcanics
   Ypr	Rhyolite of the Porcupine Volcanics
   Ypv	Porcupine Volcanics
   Ys	Siemens Creek Volcanics
   water	water

   sgmc_label

   orig_label + ;n where n= province number (n=0 if no province number)

   type: character width: 16 output width: 16 (Source: Doug Stoeser)

   Value	Definition
   Agn;0	Migmatitic gneiss and amphibolite (Late to Early Archean)
   CAm;0	Munising Formation
   CAt;0	Trempealeau Formation
   DMs;0	Sunbury Shale
   Da;0	Antrim Shale
   Db;0	Berea Sandstone
   Dbb;0	Bois Blanc Formation
   Dbd;0	Bedford Shale
   Dbe;0	Bell Shale
   Dd;0	Dundee Limestone
   Ddr;0	Detroit River Group
   De;0	Ellsworth Shale
   Dg;0	Garden Island Formation
   Dm;0	Mackinac Breccia
   Ds;0	Sylvania Sandstone
   Dt;0	Traverse Group
   Jr;0	Red beds
   Mb;0	Bayport Limestone
   Mc;0	Coldwater Shale
   Mm;0	Marshall Sandstone
   Mmi;0	Michigan Formation
   Ob;0	Big Hill Dolomite
   Obr;0	Black River Limestone
   Oc;0	Collingwood Limestone
   Op;0	Prairie du Chien Group
   Oq;0	Queenston Shale
   Os;0	Stonington Formation
   Ot;0	Trenton Limestone
   Ou;0	Utica Shale
   PAg;0	Grand River Formation
   PAs;0	Saginaw Formation
   PZu;0	Paleozoic undivided
   Sb;0	Bass Island Dolomite
   Sbb;0	Burnt Bluff Formation
   Sc;0	Cataract Formation
   Se;0	Engadine Dolomite
   Sm;0	Manistique Formation
   Sp;0	Point Aux Chenes Shale
   Ss;0	Salina Group
   Sst;0	Sainte Ignace Dolomite
   Wd;0	Dickinson Group, undivided (Late Archean)
   Wga;0	Gneiss and amphibolite (Late Archean, 2.640-2.750 Ma)
   Wgw;0	Metagraywacke (Late Archean)
   Wp;0	Puritan Quartz Monzonite (Late Archean)
   Ws;0	Biotite schist (Lake Archean)
   Wv;0	Metabasalt (Late Archean)
   Xam;0	Unexposed magnetic unit
   Xb;0	Badwater Greenstone
   Xbc;0	Blair Creek Formation
   Xc;0	Copps Formation
   Xch;0	Chocolay Group, undivided
   Xdvg;0	Dacite and volcanogenic graywacke
   Xe;0	Emperor Volcanic Complex
   Xgat;0	Athelstane Quartz Monzonite
   Xgm;0	Granitic rocks
   Xh;0	Hemlock Formation
   Xi;0	Ironwood Iron-formation
   Xm;0	Michigamme Formation, undivided
   Xmd;0	metadiabase
   Xmg;0	Metagabbro
   Xmi;0	Mafic metavolcanic rocks
   Xmmc;0	Menominee and Chocolay Groups, undivided
   Xmn;0	Negaunee Iron-formation
   Xms;0	Gray to black slate [of the Michigamme Formation]
   Xmsa;0	Composite unit of Siamo Slate and Ajibik Quartzite [of the Menominee Group]
   Xmu;0	Menominee Group, undivided
   Xmvl;0	Mafic to intermediate flows and pyroclastic rocks [in Michigamme Formation] including Clarksburg Volcanics member
   Xpi;0	Lower part of Paint River Group
   Xpp;0	Peavy Pond complex
   Xpu;0	Upper part of Paint River Group
   Xrhd;0	Rhyolite to dacite
   Xt;0	Tyler Formation
   Xvs;0	Volcanic-sedimentary unit [in the Baraga Group]
   Yc;0	Copper Harbor Conglomerate
   Ycl;0	Volcanic member of the Copper Harbor Conglomerate
   Yf;0	Freda Sandstone
   Yfc;0	Conglomerate member of Freda Sandstone
   Ygb;0	Gabbroic rocks of Keweenawan affinity
   Ygr;0	Granite associated with the Mellen complex
   Yj;0	Jacobsville Sandstone
   Yk;0	Kallander Creek Volcanics
   Ykr;0	Upper rhyolite member of the Kallander Creek Volcanics
   Yn;0	Nonesuch Shale
   Yplr;0	Rhyolite at Bergland in the Portage Lake Volcanics
   Yplv;0	Portage Lake Volcanics
   Ypr;0	Rhyolite of the Porcupine Volcanics
   Ypv;0	Porcupine Volcanics
   Ys;0	Siemens Creek Volcanics
   water;0	water

   unit_link

   composite map label = ST + sgmc_label This creates a unique identifier for every unit in the CONUS (continental United States) covers.

   type: character width: 18 output width: 18 (Source: Doug Stoeser)

   Value	Definition
   MIAgn;0	Migmatitic gneiss and amphibolite (Late to Early Archean)
   MICAm;0	Munising Formation
   MICAt;0	Trempealeau Formation
   MIDMs;0	Sunbury Shale
   MIDa;0	Antrim Shale
   MIDb;0	Berea Sandstone
   MIDbb;0	Bois Blanc Formation
   MIDbd;0	Bedford Shale
   MIDbe;0	Bell Shale
   MIDd;0	Dundee Limestone
   MIDdr;0	Detroit River Group
   MIDe;0	Ellsworth Shale
   MIDg;0	Garden Island Formation
   MIDm;0	Mackinac Breccia
   MIDs;0	Sylvania Sandstone
   MIDt;0	Traverse Group
   MIJr;0	Red beds
   MIMb;0	Bayport Limestone
   MIMc;0	Coldwater Shale
   MIMm;0	Marshall Sandstone
   MIMmi;0	Michigan Formation
   MIOb;0	Big Hill Dolomite
   MIObr;0	Black River Limestone
   MIOc;0	Collingwood Limestone
   MIOp;0	Prairie du Chien Group
   MIOq;0	Queenston Shale
   MIOs;0	Stonington Formation
   MIOt;0	Trenton Limestone
   MIOu;0	Utica Shale
   MIPAg;0	Grand River Formation
   MIPAs;0	Saginaw Formation
   MIPZu;0	Paleozoic undivided
   MISb;0	Bass Island Dolomite
   MISbb;0	Burnt Bluff Formation
   MISc;0	Cataract Formation
   MISe;0	Engadine Dolomite
   MISm;0	Manistique Formation
   MISp;0	Point Aux Chenes Shale
   MISs;0	Salina Group
   MISst;0	Sainte Ignace Dolomite
   MIWd;0	Dickinson Group, undivided (Late Archean)
   MIWga;0	Gneiss and amphibolite (Late Archean, 2.640-2.750 Ma)
   MIWgw;0	Metagraywacke (Late Archean)
   MIWp;0	Puritan Quartz Monzonite (Late Archean)
   MIWs;0	Biotite schist (Lake Archean)
   MIWv;0	Metabasalt (Late Archean)
   MIXam;0	Unexposed magnetic unit
   MIXb;0	Badwater Greenstone
   MIXbc;0	Blair Creek Formation
   MIXc;0	Copps Formation
   MIXch;0	Chocolay Group, undivided
   MIXdvg;0	Dacite and volcanogenic graywacke
   MIXe;0	Emperor Volcanic Complex
   MIXgat;0	Athelstane Quartz Monzonite
   MIXgm;0	Granitic rocks
   MIXh;0	Hemlock Formation
   MIXi;0	Ironwood Iron-formation
   MIXm;0	Michigamme Formation, undivided
   MIXmd;0	metadiabase
   MIXmg;0	Metagabbro
   MIXmi;0	Mafic metavolcanic rocks
   MIXmmc;0	Menominee and Chocolay Groups, undivided
   MIXmn;0	Negaunee Iron-formation
   MIXms;0	Gray to black slate [of the Michigamme Formation]
   MIXmsa;0	Composite unit of Siamo Slate and Ajibik Quartzite [of the Menominee Group]
   MIXmu;0	Menominee Group, undivided
   MIXmvl;0	Mafic to intermediate flows and pyroclastic rocks [in Michigamme Formation] including Clarksburg Volcanics member
   MIXpi;0	Lower part of Paint River Group
   MIXpp;0	Peavy Pond complex
   MIXpu;0	Upper part of Paint River Group
   MIXrhd;0	Rhyolite to dacite
   MIXt;0	Tyler Formation
   MIXvs;0	Volcanic-sedimentary unit [in the Baraga Group]
   MIYc;0	Copper Harbor Conglomerate
   MIYcl;0	Volcanic member of the Copper Harbor Conglomerate
   MIYf;0	Freda Sandstone
   MIYfc;0	Conglomerate member of Freda Sandstone
   MIYgb;0	Gabbroic rocks of Keweenawan affinity
   MIYgr;0	Granite associated with the Mellen complex
   MIYj;0	Jacobsville Sandstone
   MIYk;0	Kallander Creek Volcanics
   MIYkr;0	Upper rhyolite member of the Kallander Creek Volcanics
   MIYn;0	Nonesuch Shale
   MIYplr;0	Rhyolite at Bergland in the Portage Lake Volcanics
   MIYplv;0	Portage Lake Volcanics
   MIYpr;0	Rhyolite of the Porcupine Volcanics
   MIYpv;0	Porcupine Volcanics
   MIYs;0	Siemens Creek Volcanics
   MIwater;0	water

   source

   An alphanumeric code (e.g. US001) that designates the source material used.

   type: character width: 6 output width: 8 (Source: Doug Stoeser)

   Value	Definition
   MI001	Milstein, Randall L. (compiler), 1987, Bedrock geology of southern Michigan: Geological Survey Division, Michigan Dept. of Natural Resources, scale= 1:500,000
   MI002	Reed, Robert C., and Daniels, Jennifer (compilers), 1987, Bedrock geology of northern Michigan: Geological Survey Division, Michigan Dept. of Natural Resources, scale= 1:500,000
   MI003	Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigations Map I-2185, scale= 1:500,000
   MI004	Cannon, W.F., Kress, T.H., Sutphin, D.M., Morey, G.B., Meints, Joyce, and Barber-Delach, Robert, 1997, Digital Geologic Map and mineral deposits of the Lake Superior Region, Minnesota, Wisconsin, Michigan: USGS Open-File Report 97-455 (version 3, Nov. 1999), on-line only

   unit_age

   The geologic age from the source map used.

   type: character width: 60 output width: 60 (Source: Doug Stoeser)

   Value	Definition
   Archean
   Early Proterozoic
   Jurassic
   Late Archean
   Lower Devonian
   Lower Ordovician
   Lower Silurian
   Middle Devonian
   Middle Proterozoic
   Mississippian
   Mississippian-Devonian
   Paleozoic
   Pennsylvanian
   Upper Cambrian
   Upper Devonian
   Upper Ordovician
   Upper Silurian

   rocktype1

   The predominant lithology found in the formation.

   type: character width: 40 output width: 40 (Source: Johnson Lith Class 6.1)

   Value	Definition
   amphibolite
   andesite
   arkose
   basalt
   black shale
   conglomerate
   dacite
   dolostone (dolomite)
   evaporite
   gabbro
   gabbroid
   gneiss
   granite
   graywacke
   iron formation
   limestone
   mafic metavolcanic rock
   meta-basalt
   metamorphic rock
   metasedimentary rock
   metavolcanic rock
   mica schist
   quartzite
   rhyolite
   sandstone
   shale
   siltstone
   slate
   syenite
   water

   rocktype2

   The second most predominant lithology in the formation.

   type: character width: 40 output width: 40 (Source: Johnson Lith Class 6.1)

   Value	Definition
   amphibolite
   andesite
   anorthosite
   argillite
   dacite
   diabase
   dolostone (dolomite)
   gneiss
   granite
   granodiorite
   iron formation
   limestone
   metasedimentary rock
   metavolcanic rock
   migmatite
   plutonic rock (phaneritic)
   pyroclastic
   sandstone
   schist
   sedimentary breccia
   shale
   siltstone
   slate
   tuff
   ultramafic intrusive rock

   mi_geol.aat

   Arc attribute table for Michigan geologic coverage. (Source: ESRI)

   arc-code

   Unique identifier for the line feature

   type: integer width: 3 output width: 3 (Source: AAT data dictionary)

   Value	Definition
   1	contact, location certain
   7	shoreline or riverbank
   30	fault, sense of displacement unknown or undefined, location certain
   51	contact, concealed
   101	thrust fault, direction of motion undefined (i.e. teeth not shown), location certain
   124	state boundary
   125	international boundary

   arc-para1

   Used for "decorated" lines where additional information is needed.

   type: integer width: 3 output width: 3 (Source: AAT data dictionary)

   Value	Definition
   0	no additional information

   arc-para2

   "Scratch" field used mostly in Alaska.

   type: integer width: 3 output width: 3 (Source: AAT data dictionary)

   Value	Definition
   0	no additional information

   source

   An alphanumeric code (e.g. US001) that designates the source material used.

   type: character width: 6 output width: 8 (Source: Doug Stoeser)

   Value	Definition
   MI004	Cannon, W.F., Kress, T.H., Sutphin, D.M., Morey, G.B., Meints, Joyce, and Barber-Delach, Robert, 1997, Digital Geologic Map and mineral deposits of the Lake Superior Region, Minnesota, Wisconsin, Michigan: USGS Open-File Report 97-455 (version 3, Nov. 1999), on-line only
   US001	Johnson, Bruce R. and Leveritch, Beth, 1998, 1:100,000 Scale State Boundaries of the Conterminous United States: U.S. Geological Survey, unpublished (see metadata file: st100kmeta.txt, CONUSdocumentationMW.pdf)

   Entity_and_Attribute_Overview:

   Coding for polygon attributes:

   NAME: FEATURE: orig_label unmodified map unit symbols from source cover sgmc_label orig_label modified for standard geologic age symbols and an integer code added for province unit_link sgmc_label and a state code identifier source reference to source of data unit_age geologic age rocktype1 predominant lithology rocktype2 second most predominant lithology

   Coding for arc attributes:

   NAME: FEATURE: arc-code unique integer identifier arc-para1 used where additional information is needed arc-para2 scratch field source reference to source of data

   Coding for point attributes:

   NAME: FEATURE: point_feature name of feature on map source reference to source of data

   Coding for dikes (special arcs) attributes:

   NAME: FEATURE: orig_label unmodified map unit symbols from source cover sgmc_label orig_label modified for standard geologic age symbols and an integer code added for province arc-code unique integer identifier dike_lith general lithology dike_age geologic age source reference to source of data

   Entity_and_Attribute_Detail_Citation: ESRI

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Suzanne W. Nicholson
   • Connie L. Dicken
   • Michael P. Foose
   • Julia A.L. Mueller

2. Who also contributed to the data set?

   State Geologic Map Compilation (SGMC) activity of the National Surveys and Analysis projects of the US Geological Survey Mineral Resources Program.

3. To whom should users address questions about the data?
   Suzanne W. Nicholson
   U.S. Geological Survey
   12201 Sunrise Valley Dr. MS954
   Reston, VA 20192
   USA
   

   703-648-6344 (voice)
   swnich@usgs.gov
   

Why was the data set created?

A primary goal of this work is to develop geologic map datasets with standardized structure and attribution. The database design and standards are documented in CONUSdocumentationMW.pdf of this series. The intent is that contiguous databases can be merged seamlessly and without any additional effort. In addition to a common database structure, the conterminous U.S. state databases (the contiguous 48 states) have been fitted to a set of standard state boundaries so that, when states are merged, they match without slivers or overlap. No attempt has been made to reconcile differences in mapping across state boundaries.

How was the data set created?

1. From what previous works were the data drawn?

   MI001 (source 1 of 6)

   Michigan Geological Survey Division, and Milstein, Randall L. (compiler), 1987, Bedrock geology of southern Michigan: none none, State of Michigan, Department of Natural Resources, Geological Survey, Lansing, Michigan.

   Online Links:

   • none

   Source_Scale_Denominator: 500,000

   Source_Contribution: provided linework for the geology coverage.

   MI002 (source 2 of 6)

   Michigan Geological Survey Division, Reed, Robert C. (compiler), and Daniels, Jennifer (compiler), 1987, Bedrock geology of northern Michigan: none none, State of Michigan, Department of Natural Resources, Geological Survey, Lansing, Michigan.

   Online Links:

   • none

   Type_of_Source_Media: paper map

   Source_Scale_Denominator: 500,000

   Source_Contribution: provided linework for the geology coverage.

   MI003 (source 3 of 6)

   Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigation Map I-2185, U.S. Geological Survey, Reston, Virginia.

   Online Links:

   • none

   Type_of_Source_Media: paper map

   Source_Scale_Denominator: 500,000

   Source_Contribution: provided unit descriptions where available.

   MI004 (source 4 of 6)

   Cannon, W.F., T.H., Kress., Sutphin, D.M., Morey, G.B., Meints, Joyce, and Barber-Delach, Robert, 1997, Digital Geologic Map and mineral deposits of the Lake Superior Region, Minnesota, Wisconsin, Michigan: U.S. Geological Survey Open-File Report OFR 97-455, U.S. Geological Survey, Reston, Virginia.

   Online Links:

   • <http://pubs.usgs.gov/of/of97-455/>

   Type_of_Source_Media: digital map

   Source_Scale_Denominator: 500,000

   Source_Contribution: provided unit descriptions where available.

   US001 (source 5 of 6)

   Johnson, Bruce R., and Leveritch, Beth, unpublihsed material, 1:100,000 Scale State Boundaries of the Conterminous United States.

   Type_of_Source_Media: online

   Source_Scale_Denominator: 100,000

   Source_Contribution: Provided linework for state boundaries

   Johnson Lith Class 6.1 (source 6 of 6)

   Johnson, Bruce R., unpublished material, Geologic Map Unit Classification, ver. 6.1.

   Type_of_Source_Media: online; <http://geology.usgs.gov/dm>

   Source_Scale_Denominator: none

   Source_Contribution: Classification scheme used for lithology.

2. How were the data generated, processed, and modified?

   Date: 2003 (process 1 of 10)

   The purpose of this standardization is to allow all SGMC covers to be seamlessly joined without any additional effort to form regional or national level digital maps. Note that for Alaska, the state is being compiled as blocks of 1:250k quadrangles that will ultimately be used to compile a new state map. Douglas Stoeser and Ric Wilson are co-coordinators for the overall SGMC effort, with Stoeser coordinating work on the mainland states and Wilson coordinating work for Alaska and Hawaii.

   Date: 01-Apr-2004 (process 2 of 10)

   C.L. Dicken obtained the digital geologic map of Michigan from the following website: <http://pubs.usgs.gov/of/of97-455/>

   Dicken extracted the linework for the Michigan piece of the dataset and re-projected the coverage into the following:

   projection: Lambert Conformal Conic units: meters datum: NAD27 standard parallel 1: 33 0 0.000 standard parallel 2: 45 0 0.000 central meridian: -100 0 0.000 reference latitude: 0 0 0.000 false easting: 0.00000 false northing: 0.00000

   All attributes were deleted except symbol.

   (Note: Attributes associated with the generation of the coverages were not deleted. PAT - shape, area, perimeter, coverage#, and coverage-id AAT - shape, fnode#, tnode#, lnode#, rnode#, length, coverage#, and coverage-id)

   The values from symbol where then calculated into a new field called orig_label.

   Date: 05-Apr-2004 (process 3 of 10)

   The relevant state outline (arcs) was removed from the coverage and replaced with the arcs from the 1:100,000 Scale State Boundaries of the Conterminous United States.

   This allows for a seamless fit of each state to a standard state boundary base.

   Date: 06-Apr-2004 (process 4 of 10)

   The following attributes were exported from Filemaker as a .dbf: orig_label, map_symbol2, unit_link, reference_id, unit_age, rocktype1, and rocktype2.

   orig_label reflects the original map symbol used on the source map

   map_symbol2 reflects map-symbol1 with the addition of a province number

   unit_link is an auto generated field based on map-symbol2 and the state abbreviation (e.g. IN001) that produces a unique identifier for each map unit

   reference_id was populated with an alphanumeric code (e.g. US001) that designates the source used for the linework and other references used to describe the age or lithologies of the unit.

   unit_age was populated with general age assignment

   rocktype1 records dominant lithology (must be >50% of unit), using standardized data dictionary

   rocktype2 records second most dominant lithology, using standardized data dictionary

   orig_label has the following field names from the source map:

   bed-geo in Illinois map_code in Indiana symbol in Michigan symbol in Wisconsin map_label in Minnesota

   The attributes were then converted using the following structure:

   item name: orig_label width: 12 output: 12 type: c

   item name: sgmc_label width: 16 output: 16 type: c

   item name: unit_link width: 18 output: 18 type: c

   item name: source width: 6 output: 8 type: c

   item name: unit_age width: 60 output: 60 type: c

   item name: rocktype1 width: 40 output: 40 type: c

   item name: rocktype2 width: 40 output: 40 type: c

   Date: 06-Apr-2004 (process 5 of 10)

   Once the .dbf was in the correct format with standardized column widths and data structure, it was converted into a lookup table (.lut) in Arc/Info. Then a joinitem was performed to join the look-up table to the polygon attribute table. orig_label was used as the merge item.

   Date: 06-Apr-2004 (process 6 of 10)

   Next, in preparing the uniform .aat file, the following items were added to the table:

   item name: arc-code width: 3 output: 3 type: i

   item name: arc-para1 width: 3 output: 3 type: i

   item name: arc-para2 width: 3 output: 3 type: i

   item name: source width: 6 output: 8 type: c

   Date: 06-Apr-2004 (process 7 of 10)

   Arc-code was populated using the paper map source to tag the lines using the AAT line type data dictionary (see CONUSdocumentationMW.pdf).

   Arc-para1 was populated when additional information was available such as identifying the upthrown side of a fault or direction of thrusting on a fault. (see CONUSdocumentationMW.pdf)

   Arc-para2 is a scratch field that is used mostly in Alaska.

   Source was populated with an alphanumeric code (e.g. US001) that designates the source used for the linework.

   Date: 23-Apr-2004 (process 8 of 10)

   Once the .aat and the .pat were populated with the correct attributes, the coverage was exported as an .e00 file (migeol_lcc.e00).

   Then it was unprojected into geographic coordinates and exported again (migeol_dd.e00).

   Date: 04-May-2004 (process 9 of 10)

   The faults were extracted to generate a separate fault file. PUT was the command used to copy the line features from the geology line coverage into a new fault line coverage.

   The data were exported as an .e00 file (mifaults_lcc.e00) and then unprojected into geographic coordinates and exported again (mifaults_dd.e00).

   Date: 04-May-2004 (process 10 of 10)

   Finally, the geology lines, geology polygons and fault line coverages were converted into shapefiles; in both geographic coordinates and in Lambert Conformal Conic projection.

3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?

   The values of the attributes ROCKTYPE1 and ROCKTYPE2 were assigned based on the information in the legends of the source maps (most of which are paper). The definitions of these values are described in the draft document Geologic Map Classification version 6.1 (Johnson and others); available at the following website: <http://geology.usgs.gov/dm>

2. How accurate are the geographic locations?

   Accuracy of Michigan state boundary and those arcs intersecting it: The accuracy of the state boundary arcs is based on the 1:100,000 scale original data used to produce this boundary. (Johnson, Bruce R. and Leveritch, Beth, 1998, 1:100,000 Scale State Boundaries of the Conterminous United States: U.S. Geological Survey, unpublished (see metadata file: st100kmeta.txt, CONUSdocumentationMW.pdf)).

   Those internal arcs intersecting the state boundary were extended or shortened as needed to complete polygons, possibly creating a small amount of error.

3. How accurate are the heights or depths?

4. Where are the gaps in the data? What is missing?

   Bodies of water are classified as water, and the geologic units underlying them are not included in this coverage.

5. How consistent are the relationships among the observations, including topology?

   All internal polygons were checked for closure with vendor software and on hard copy plots. Overshoots and undershoots have been deleted or corrected as appropriate.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: none

Use_Constraints:

This database is not meant to be used or displayed at any scale other than 1:500,000.

Any hardcopies utilizing these data sets shall clearly indicate their source. If the licensee has modified the data in any way they are obligated to describe the types of modifications they have performed on the hardcopy map. Licensee specifically agrees not to misrepresent these data sets, nor to imply that changes they made were approved by the U.S. Geological Survey.

1. Who distributes the data set? (Distributor 1 of 1)
   U.S. Geological Survey Information Services Reston-ESIC
   U.S. Geological Survey
   507 National Center
   Reston, Virginia 20192
   USA
   

   1-888-ASK-USGS or 1-703-648-5953 (voice)
   <http://www.usgs.gov/contact/>
   

2. What's the catalog number I need to order this data set?

   USGS OFR 2004-1355

3. What legal disclaimers am I supposed to read?

   Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the USGS. Although these data have been used by the USGS and have been successfully imported into data base programs, no warranty, expressed or implied, is made by the USGS as to how successfully or accurately the data can be imported into any specific application software running on any specific hardware platform. The fact of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith. This data base GIS is not meant to be used or displayed at any scale other than 1:500,000.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	Geologic units and structural features in format ARC/INFO export (version 8.3)
     Network links:	<http://pubs.usgs.gov/of/2004/1355/>

   • Cost to order the data: none

Who wrote the metadata?

Dates:

Last modified: 18-May-2004

Metadata author:

U.S. Geological Survey
Attn: Connie L. Dicken
12201 Sunrise Valley Dr. MS954
Reston, VA 20192
USA

703-648-6482 (voice)
cdicken@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)