The Central African Republic Diamond Database (2018) - Surficial Geology

Frequently anticipated questions:

• What does this data set describe?
  1. How might 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?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Chirico, Peter G., DeWitt, Jessica D., and Bergstresser, Sarah E., 2018, The Central African Republic Diamond Database (2018) - Surficial Geology: U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9NFPUEO

   This is part of the following larger work.
   DeWitt, Jessica D., Chirico, Peter G., Bergstresser, Sarah E., and Clark, Inga E., 2018, The Central African Republic Diamond Database – A Geodatabase of Archival Diamond Occurrences and Areas of Recent Artisanal and Small-scale Diamond Mining: U.S. Geological Survey, Reston, VA.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: 14.765624995817
   East_Bounding_Coordinate: 27.421874995312
   North_Bounding_Coordinate: 11.048608926563
   South_Bounding_Coordinate: 2.8548257978545
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 2018

   Currentness_Reference:

   publication date

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

   Geospatial_Data_Presentation_Form: ESRI feature class (polygon) data
   

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?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 1.0. Longitudes are given to the nearest 1.0. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_WVG_1984.
      The ellipsoid used is GRS 1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257223563.
      
7. How does the data set describe geographic features?

   Surficial_Geology

   attribute table for Surficial_geology GIS polygons (Source: unknown)

   USGS_ATT

   USGS attribute describing the major geochronologic epoch of each bedrock unit. (Source: U.S. Geological Survey) Eoarchean, Paleoarchean, Mesoarchean, Neoarchean, Paleoproterozoic, Mesoproterozoic, Neoproterozoic, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous, Paleogene-eogene, Quaternary

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Peter G. Chirico
   • Jessica D. DeWitt
   • Sarah E. Bergstresser
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   Peter G. Chirico

   U.S. Geological Survey

   12201 Sunrise Valley Dr.

   Reston, VA
   

   USA

   703-648-6950 (voice)

   pchirico@usgs.gov

Why was the data set created?

The polygons in this dataset provide country-scale geologic context for the geomorphologic terrain elements, which are the focus of investigations regarding alluvial and fluvial placer diamond deposits.

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 2017 (process 1 of 1)

   Mapped geologic data presented in conference proceedings was digitized and adapted for use in this study. The full citation of this data source is: Lescuyer, J.L., and Milési, J.P., 2004, Africa GIS and SIGAfrique network – Geological and metallogenic information system, tools for sustainable development: France, 20éme Colloque de Géologie Africaine.

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?
   No formal attribute accuracy tests were conducted
2. How accurate are the geographic locations?
   No formal positional accuracy tests were conducted
3. How accurate are the heights or depths?
   No formal positional accuracy tests were conducted
4. Where are the gaps in the data? What is missing?
   Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   No formal logical accuracy tests were conducted

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:

Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. The U.S. Geological Survey requests to be acknowledged as originator of these data in future products or derivative research.

1. Who distributes the data set? (Distributor 1 of 1)
   
   Peter G. Chirico

   U.S. Geological Survey

   12201 Sunrise Valley Dr.

   Reston, VA
   

   USA

   703-648-6950 (voice)

   pchirico@usgs.gov
2. What's the catalog number I need to order this data set?
3. What legal disclaimers am I supposed to read?

   Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. The U.S. Geological Survey requests to be acknowledged as originator of these data in future products or derivative research.

4. How can I download or order the data?
5. What hardware or software do I need in order to use the data set?

   This dataset is formatted as a feature class in a ESRI geodatabase. It requires the user to have geospatial software such as ESRI ArcGIS, Blue Marble Global Mapper, Que GIS, GRASS, or other GIS software

Who wrote the metadata?

Dates:

Last modified: 09-Apr-2018

Metadata author:

Jessica DeWitt

U.S. Geologic Survey

12201 Sunrise Valley Dr.

Reston, VA

USA

703-648-6926 (voice)

jdewitt@usgs.gov

Metadata standard:

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