Surface Geology

Geo2_7t  - ArcInfo coverage (Mercator projection),

Geo2_7g  - ArcInfo coverage (Geographic coordinates),

geo2_7.shp - ArcView shape file

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: U.S. Geological Survey

Publication_Date: 200206

Publication_Time: Unknown

Title: Map showing Geology, Oil and Gas Fields, and

          Geologic Provinces of Africa, version 2.0

Edition: 2

Geospatial_Data_Presentation_Form: vector digital data

Online_Linkage: <http://energy.cr.usgs.gov>

Description:

Abstract:

geo2_7 - Surficial geology. ArcInfo polygon coverage. Item "glg" in Feature Attribute Table (FAT) is for geologic age.

Purpose:

The Data provide Government, geological community, consultants, and public with information on geologic basis of African

continent. It intented to use as a reference spatial data.

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 2002

Currentness_Reference: publication date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -22.413353

East_Bounding_Coordinate: 64.540365

North_Bounding_Coordinate: 40.003867

South_Bounding_Coordinate: -38.574876

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: Surface geology

Place:

Place_Keyword: Africa

Access_Constraints: None

Use_Constraints: None

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: U.S. Geological Survey, Central Region

Contact_Position: U.S.G.S. contractor

Contact_Address:

Address_Type: mailing and physical address

Address:

U.S. Geological Survey Energy Resource Team, Box 25046, Denver Federal Center, MS 939

City: Denver

State_or_Province: CO

Postal_Code: 80225-0046

Country: USA

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 8:00 am - 4:00 pm MST

Browse_Graphic:

Browse_Graphic_File_Name: africa.pdf

Browse_Graphic_File_Type: PDF

Data_Set_Credit:

Digital Map Compilation - Feliks Persits

Geological Attribution - Feliks Persits, Thomas Ahlbrandt, Michelle Tuttle, Ronald Charpentier, Michael Brownfield

Security_Information:

Security_Classification: Unclassified

Native_Data_Set_Environment:

Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 2; ESRI ArcCatalog 8.1.1.649

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Standard ARC/INFO attributes accuracy in Feature Attributes Tables like AREA, PERIMETER, etc. depend on horizontal

positional accuracy. All the additional attributes are character type.

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Explanation:

All the Attributes besides standard ARC/INFO are character type. Standard verification of attributes reliability has been

done by ARC/INFO EDITPLOT program to find out polygons without assigned character value or with more than one value.

Logical_Consistency_Report:

Since Data set is the ARC/INFO coverage topological consistency are supported. Fuzzy tolerance has been maintained the same through

all processing steps. Based on fuzzy tolerance value all undershoots and overshoots were detected and deleted.

A comparison between color plot and original paper map was carried out by visual comparison. Color plots in 1:5,000,000 scale were

superimposed on every of correspondent original map sheets. All detected errors in attributes were corrected.

Completeness_Report:

            Several geologic age subdivisions on the original (UNESCO) 1:5,000,000 geologic map were combined into single unit.

 As of May, 2000 generalizations of the original geologic map (UNESCO) were carried out:

 1.  All the Cretaceous units were combined into one.

 2. All the Precambrian subdivisions were combined into one.

Boundaries are correct as of July, 1997.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

1. Original geological maps are of 500 m. maximum accuracy (0.1 mm on paper map of 1:5,000,000 scale).

2. Scanned images were of 200 dot/inch resolution (0.12 mm on paper). That is why fuzzy tolerance for CLEAN program

in ARC/INFO was set to 500 m. Average positional accuracy can be evaluated as 1000 m (twice of fuzzy tolerance).

Quantitative_Horizontal_Positional_Accuracy_Assessment:

Horizontal_Positional_Accuracy_Value: 1000 m

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: Commission for the Geological Map of the World (CGMW)

Publication_Date: 1990

Title: Carte géologique internationale de l'Afrique

Edition: 1987-1990

Geospatial_Data_Presentation_Form: map

Source_Scale_Denominator: 5000000

Type_of_Source_Media: Paper Geologic Map

Source_Time_Period_of_Content:

Source_Currentness_Reference: publication date

Source_Citation_Abbreviation: Paper Geologic Map

Source_Contribution:

All the five paper map sheets are used as the sources for creation the correspondent ARC/INFO coverages.

Process_Step:

Process_Description:

Transparent mylar film was used to extract geologic boundaries from paper geologic maps.

Process_Date: 1996

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Dr. Thomas Ahlbrandt

Contact_Organization: U.S. Geological Survey

Contact_Position: Project Chief

Contact_Voice_Telephone: 303-236-5776

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: ahlbrandt@usgs.gov

Hours_of_Service: 8 - 5 MST

Process_Step:

Process_Description:

Scanning mylars on large format Anatech Eagle scanner in binary mode. Vectorizing binary images in UNIX

ArcInfo 7.0.1 to produce ArcInfo coverages by GRIDLINE utility.

Source_Used_Citation_Abbreviation: Mylar scanning

Process_Date: 1996

Source_Produced_Citation_Abbreviation: ArcInfo coverages from binary images

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Ronald Charpentier

Contact_Organization: US Geological Survey

Contact_Position: Senior Geologist

Contact_Voice_Telephone: 303-236-5766

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: charpentier@usgs.gov

Hours_of_Service: 8 - 5 MST

Process_Step:

Process_Description:

Scanning original paper maps on a large format Anatech Eagle scanner in gray-scale mode.

Source_Used_Citation_Abbreviation: Paper maps

Process_Date: 1997

Source_Produced_Citation_Abbreviation: Gray-scale images

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: US Geological Survey

Contact_Position: GIS Contractor

Contact_Address:

Address_Type: mailing and physical address

Address: Denver Federal Center, P.O. Box 25046, MS 939

City: Denver

State_or_Province: CO

Postal_Code: 80225

Country: USA

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 8 - 5 MST

Process_Step:

Process_Description:

Geologic age attributes were assigned to ArcInfo polygon coverage

Source_Used_Citation_Abbreviation: ArcInfo coverages from binary images

Process_Date: 1996

Source_Produced_Citation_Abbreviation: Attributed ArcInfo coverages from binary images

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Ronald. Charpentier

Contact_Organization: US Geologcal Survey

Contact_Position: GIS Contractor

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 5 - 8 MST

Process_Step:

Process_Description:

ArcInfo coverages from binary images were transformed to Transverse Mercator projection with central meridian

of 16⁰ E and scale factor at a central meridian equal to 0.995.

Source_Used_Citation_Abbreviation: Attribited ArcInfo coverages

Process_Date: 1996

Source_Produced_Citation_Abbreviation: Projected ArcInfo coverages from binary images

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: US Geological Survey

Contact_Position: GIS Contractor

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 5 - 8 MST

Process_Step:

Process_Description:

Gray-scale images were georeferenced by ArcInfo REGISTER and RECTIFY utilities by using projected

ArcInfo coverages from binary images.

Source_Used_Citation_Abbreviation: Gray-scale images

Process_Date: 1997

Source_Produced_Citation_Abbreviation: Georeferenced gray-scale images

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: U.S. Geological Survey

Contact_Position: GIS Contractor

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 5 - 8 MST

Process_Step:

Process_Description:

Verification and correction of line work and geologic attributing of projected ArcInfo coverages by using

georeferenced gray-scale images as background images in ArcInfo ArcEdit 7.0.2

Source_Used_Citation_Abbreviation: Projected ArcInfo coverages

Process_Date: 1997

Source_Produced_Citation_Abbreviation: Corrected ArcInfo coverages

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: U.S. Geological Survey

Contact_Position: GIS Contractor

Contact_Address:

Address_Type: mailing and physical address

Address: Denver Federal Center, P.O. Box 25046, MS 939

City: Denver

State_or_Province: CO

Postal_Code: 80225

Country: USA

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 8 - 5 MST

Process_Step:

Process_Description:

Corrected ArcInfo coverages were projected to geographic coordinates and to Mercator projection

with a central meridian of 25⁰ E by ArcInfo PROJECT utility.

Source_Used_Citation_Abbreviation: Corrected ArcInfo coverages

Process_Date: 1997

Source_Produced_Citation_Abbreviation:

Final ArcInfo coverages in Mercator projection and in geographic coordinates.

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Feliks Persits

Contact_Organization: GIS Contractor

Contact_Address:

Address_Type: mailing and physical address

Address: Denver Federal Center, P.O. Box 25046, MS 939

City: Denver

State_or_Province: CO

Postal_Code: 80225

Country: USA

Contact_Voice_Telephone: 303-236-3612

Contact_Facsimile_Telephone: 303-236-8822

Contact_Electronic_Mail_Address: fpersits@usgs.gov

Hours_of_Service: 5 - 8 MST

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: G-polygon

Point_and_Vector_Object_Count: 11977

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Map_Projection:

Map_Projection_Name: Mercator

Mercator:

Standard_Parallel: 0.00

Longitude_of_Central_Meridian: 25.00

False_Easting: 0.00

False_Northing: 0.00

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.016384

Ordinate_Resolution: 0.016384

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: D_WGS_1984

Ellipsoid_Name: WGS_1984

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257224

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: geo2_7t_polygon

Attribute:

Attribute_Label: OBJECTID

Attribute:

Attribute_Label: Shape

Attribute_Definition: Feature geometry.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Coordinates defining the features.

Attribute:

Attribute_Label: AREA

Attribute_Definition: Area of polygon

Attribute_Definition_Source: Software computed
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 928710.10
Range_Domain_Maximum: 3067273961704.0

Attribute:

Attribute_Label: PERIMETER

Attribute_Definition: Perimeter of polygon

Attribute_Definition_Source: Software computed
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4588.40
Range_Domain_Maximum: 169603590.891

Attribute:

Attribute_Label: GEO2_7T_

Attribute_Definition: Internal ID

Attribute_Definition_Source: Software computed
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2
Range_Domain_Maximum: 11978

Attribute:

Attribute_Label: GEO2_7T_ID

Attribute_Label: GEO2_ID

Attribute_Definition: User ID

Attribute_Definition_Source: Software computed
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 11994

Attribute:

Attribute_Label: GLG

Attribute_Definition: Surface Geology Attribute

Attribute_Definition_Source: U.S.Geological Survey

Enumerated_Domain:

"Q" - Quaternary (undivided)
 "Qe" - Holocene
 "Qp" - Pleistocene
 "QT" - Cenozoic
 "T" - Tertiary
 "Mz" - Mesozoic
 "TK" - Tertiary-Cretaceous
 "K" - Cretaceous
 "Kl" - Lower Creteceous"
 "KJ" - Cretaceous-Jurassic
 "J" - Jurassic
 "Jl" - Lower Jurassic
 "JTr" - Jurassic-Triassic
 "Tr" - Triassic
 "Trl" - Lower Triassic
 "MzPz" - Mesozoic-Paleozoic
 "KC" - Cretaceous-Carboniferous
 "JC" - Jurassic-Carboniferous
 "Pz" - Paleozoic
 "P" - Permian
 "TrP" - Triassic-Permian
 "PC" - Permian-Carboniferous
 "C" - Carboniferous
 "CD" - Carboniferos-Devonian
 "D" - Devonian
 "Du" - Upper/Middle Devonian
 "DS" - Devonian-Silurian
 "S" - Silurian
 "SO" - Silurian-Ordovician
 "OCm" - Ordovician-Camrian
 "pCm" - Precambrian
 "PzpC" - Paleozoic-Precambrian
 "Qv" - Quaternary Igneous
 "Ti" - Tertiary Igneous
 "Mi" - Mesozoic Igneous
 "MiPi" - Mz-Pz Igneous
 "Pi" - Paleozoic Igneous
 "Kimb" - Kimberlites
 "S_d" - Salt Domes
 "H2O" - Water (River 0r Lake)
 "Sea" - Sea
 "oth"S_d" - Areas outside of African Continent"
Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey.

Attribute:

Attribute_Label: Shape_Length

Attribute_Definition: Length of feature in internal units.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Positive real numbers that are automatically generated.

Attribute:

Attribute_Label: Shape_Area

Attribute_Definition: Area of feature in internal units squared.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Positive real numbers that are automatically generated.

Distribution_Information:

Distributor:

Contact_Information:

          Contact_Organization: U.S. Geological Survey Earth Science Information Center (ESIC)

Contact_Person_Primary:Dorothy Tanti

Contact_Address:

Address_Type: mailing and physical address

Address:

U.S.Geological Survey Box 25046 Building 25 Denver Federal Center

City: Denver

State_or_Province: CO

Postal_Code: 80225-0286

Country: USA

Contact_Voice_Telephone: 303.236.1647

Contact_Electronic_Mail_Address: eteamdisks@usgs.gov

Hours_of_Service: 8:00 am - 4:00 pm MST

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ARCE

Format_Specification:

ArcInfo coverage

ArcView shape file

ARC/INFO Export format

ARC/INFO Generate format ASCII file, formatted for text attributes

SDTS Spatial Data Transfer Standard (Federal Information Processing Standard 173)

Metadata_Reference_Information:

Metadata_Date: 20011019

Metadata_Contact:

              Contact_Information:

                         Contact_Organization_Primary:
                                    Contact_Organization: U.S. Geological Survey
                                    Contact_Person: David A. Ferderer
                                    Contact_Position: Data library manager, Central Energy Resources Team
                         Contact_Address:
                                    Address_Type:mailing and physical address
                                   Address: U.S. Geological Survey, MS 939 Box 25046 Denver Federal Center
                                   City: .Denver
                                   State_or_Province: CO.
                                   Postal_Code: 80225-0046
                                   Contact_Voice_Telephone: (303) 236-3611
                                   Contact_Facsimile_Telephone: (303) 236-8822
                                   Contact_Electronic_Mail_Address: dferdere@usgs.gov

                                   Hours_of_Service: 8 am. to 4 pm. MST

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile

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U.S. Department of the Interior | U.S. Geological Survey URL: <http://pubs.usgs.gov/of/1997/ofr-97-470/OF97-470A/geo2_7.htm> Contact: Energy Program Inquiries Questions or Assistance: Contact USGS Page Last Modified: Fri Jul 16 15:52 EST 2004