Dwight C. Bradley, Paul O’Sullivan, Michael Cosca, Holly Motts, John Horton, Cliff Taylor, Georges Beaudoin, Gregory Lee, Jahan Ramezani, Dan Bradley, Jamey Jones, Samuel Bowring, and Stuart Giles
2015
Geology of Mauritania, West Africa
vector digital data
Denver, CO
U.S. Geological Survey
http://dx.doi.org/10.3133/ofr20131280Taylor, Cliff D., ed.2015Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II) phase VPDFs, Digital Maps, Excel tablesU.S. Geological Survey Open-File ReportOF 2013-1280Denver, ColoradoU.S. Geological Surveyhttp://pubs.usgs.gov/of/2013/1280/
Polygons representing the geology in the Islamic Republic of Mauritania (IRM), Africa at 1:1 million scale as compiled by Dwight Bradley and explained in the geology report.
Created for the "Second Projet de Renforcement Institutionnel du Secteur Minier (PRISM II)" co-financed by the Government of Mauritania and the World Bank (Credit No. IDA-38100 MAU). This data was used in the creation of the map: Geologic Map of Mauritania. This dataset was used extensively in numerous reports related to the project. In particular, the hydrology and delineation of mineral deposit permissive tracts within various other reports relied heavily on this dataset.
2013
None planned
-17.372469
-4.719624
27.317428
14.649486
None
geology
None
Africa
Mauritania
None
Data have been checked to ensure the accuracy of the data. If any errors are detected, please notify the originating office. The U.S. Geological Survey strongly recommends that careful attention be paid to the metadata file associated with these data. Acknowledgement of the U.S. Geological Survey would be appreciated in products derived from these data. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ArcGIS and ERDAS Imagine formats, this metadata file may include some terminology specific to those software packages.
This digital database is not meant to be used or displayed at any scale larger than 1:1,000,000
John Horton
U.S. Geological Survey
GIS Analyst
mailing and physical address
Denver Federal Center, PO Box 25046, MS-973
Denver
CO
80228
303-236-1921
jhorton@usgs.gov
Dwight C. Bradley, Paul O’Sullivan, Michael Cosca, Holly Motts, John Horton, Cliff Taylor, Georges Beaudoin, Gregory Lee, Jahan Ramezani, Dan Bradley, Jamey Jones, Samuel Bowring, and Stuart Giles
Microsoft Windows 7 Version 6.1 (Build 7600) ; ESRI ArcGIS 10.0.4.4000
Attribute accuracy is dependent on the original data received from the Government of Mauritania (Ministere du Petrole, de I'Energies et des Mines) originally created for the Projet de Renforcement Institutionnel du Secteur Minier (PRISM I). New attributes and the original attributes have been modified by authors. Frequency and summary statistics were performed on attribute fields to check for inconsistencies.
Topology was enforced on this dataset to eliminate any duplicates, overlaps or gaps between polygons.
Complete
The horizontal positional accuracy of the polygons may vary depending on the accuracy of the original datasets received from the Government of Mauritania (Ministere du Petrole, de I'Energies et des Mines) originally created for the Projet de Renforcement Institutionnel du Secteur Minier (PRISM I).
From the geology report: The USGS Mauritania project was provided with 32 individual shapefiles of the British Geological Survey (BGS) 1:200,000-scale (200K) geologic mapping and three shapefiles of the BGS 1:500,000-scale (500K) geologic mapping (North1, North2, and South). The 500K files already had the 200K files burned into them. These merged 500K maps had been subject to an automated GIS smoothing routine; many vertices were deleted during this procedure, altering the geologic contacts. The merged 500K maps also had been simplified, with the deletion of certain geologic polygons that we deemed too important to not show. We therefore opted to revert to all the original 200K shapefiles, and used the 500K maps only where this was the only option. The problem just described resulted in linework discrepancies between 200K and 500K maps. Minor GIS-induced discrepancies were rectified using Google Earth imagery.
Another source that we consulted is a new bedrock geologic map of Mauritania at 1:1,000,000 scale, which was compiled by BRGM (Lahondère and others, 2010) while the present study was underway. The GIS database used to generate that map was not provided to USGS, but a rasterized pdf was.
2011-2012
John Horton
U.S. Geological Survey
GIS Analyst
mailing and physical address
Denver Federal Center, PO Box 25046
MS 973
Denver
CO
80228
303-236-1921
jhorton@usgs.gov
Vector
G-polygon
24417
Transverse Mercator
0.9996
-11.0
0.0
0.0
0.0
coordinate pair
0.6096
0.6096
meters
WGS 1984
WGS_1984
6378137
298.257224
Attribute Table
Table containing attribute information associated with the data set.
Authors
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
ESRI
Coordinates defining the features.
NOTATION
Unique symbol created by the authors to represent the new 1:1 million scale geologic units.
Authors
User defined
SUPER_GROU
Super Group name (in French).
Authors
User defined
GROUPE
Group name (in French).
Authors
User defined
SOUS_GROUP
Sub-Group name (in French).
Authors
User defined
ORIG_NOTAT
The symbols of the original geology (from the 200K and/or 500K geology received from the Mauritania government). Allows user to see what original geologic units were combined for this new 1:1 million scale geologic data.
Authors
User defined
ÈRE
The geologic age of the unit (English equivalent is ERA and/or EON). Terms are in French.
Authors
User defined
SYSTÈME
The geologic age of the unit (English equivalent is Period). Terms are in French.
Authors
User defined
DATE_EN_MA
Numeric age range of geologic unit (if known). Values represented as Ma.
Authors
User defined
LITH_ENG
Lithologic description for each unit (in English).
Authors
User defined
LITH_FRA
Lithologic description for each unit (in French).
Authors
User defined
SIMPCODE
Unique code for each unit used to simplify the geology into specific lithologic groups.
Authors
User defined
SDESC_ENG
Description of each SIMPCODE (in English). Authors created these fields in an attempt to simplify the geology into smaller groups of lithologic units.
Authors
User defined
SDESC_FRA
Description of each SIMPCODE (in French). Authors created these fields in an attempt to simplify the geology into smaller groups of lithologic units.
Authors
User defined
Length
Length of polyline in meters.
ESRI
62.413197
33750918.5822
meters
Area
Area of polygon in meters squared.
ESRI
95.785872
339619277876
square meters
U.S. Geological Survey
mailing address
USGS Information Services
Denver
CO
80225-0046
Box 25286Denver Federal Center
1-888-ASK-USGS (1-888-275-8747)
http://ask.usgs.gov
Downloadable Data
This database, identified as OF 2013-1280, has been approved for release and publication by the U.S. Geological Survey. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the U.S. Government may be held liable for any damages resulting from its authorized or unauthorized use.
Although these data have been processed successfully on a computer System at the U.S. Geological Survey (USGS), no warranty, expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data described and/or contained herein.
Although this information product, for the most part, is in the public domain, it also contains copyrighted material as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.
Shapefilehttp://dx.doi.org/10.3133/ofr20131280http://pubs.usgs.gov/of/2013/1280/None
20150720
John Horton
U.S. Geological Survey
GIS Analyst
mailing and physical address
Denver Federal Center, PO Box 25046
MS 973
Denver
CO
80228
303-236-1921
jhorton@usgs.gov
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time