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1995 National Oil and Gas Assessment Conventional Plays within the Iowa Shelf Province

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?
  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 should this data set be cited?

   United States Geological Survey (USGS), 1996, 1995 National Oil and Gas Assessment Conventional Plays within the Iowa Shelf Province: U.S. Geological Survey Digital Data Series DDS-30, USGS Central Energy Team, Denver, Colorado.

   Online Links:

   • <http://energy.cr.usgs.gov/oilgas/noga/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -96.63970999

   East_Bounding_Coordinate: -90.14005822

   North_Bounding_Coordinate: 44.71380462

   South_Bounding_Coordinate: 40.3754371

3. What does it look like?

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

   Calendar_Date: 1996

   Currentness_Reference: 1996

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

   Geospatial_Data_Presentation_Form: vector digital 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. It contains the following vector data types (SDTS terminology):

      • Complete chain
      • Entity point
      • GT-polygon composed of chains
      • Point

   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 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees.

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222.
      

7. How does the data set describe geographic features?

   pr"playnum"g.pat or pr"playnum"g.dbf

   Polygon Attribute Table. For each play, "playnum" is replaced with the actual play number in either a file, pr"playnum"g.pat, or a table, pr"playnum"g.dbf. (Source: U.S. Geological Survey)

   REG_NUM

   Region Number (Source: U.S. Geological Survey Energy Resource Regions)

   Value	Definition
   7	Midcontinent

   REG_NAME

   Region Name (Source: U.S. Geological Survey Energy Resource Regions)

   Value	Definition
   Midcontinent

   PROV_NUM

   Province Number (Source: U.S. Geological Survey Energy Resource Provinces)

   Value	Definition
   52	Iowa Shelf

   PROV_NAME

   Province Name (Source: U.S. Geological Survey Energy Resource Provinces)

   Value	Definition
   Iowa Shelf

   PLAY_NUM

   Play Number (Source: U.S. Geological Survey Energy Resource Plays)

   Value	Definition
   5201	Middle Ordovician

   PLAY_NAME

   Play Name (Source: U.S. Geological Survey Energy Resource Plays)

   Value	Definition
   Middle Ordovician

   OIL_F95

   95% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F90

   90% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F75

   75% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F50

   50% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F25

   25% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F10

   10% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F5

   5% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_F1

   1% Fractile estimates for the distribution of volume of undiscovered oil for the entire play (in millions of barrels) (Source: USGS DDS-36)

   stored as a floating-point value

   OIL_MEAN

   The mean estimate of volume of undiscovered oil (in millions of barrels). (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F95

   95% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F90

   90% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F75

   75% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F50

   50% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F25

   25% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F10

   10% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F5

   5% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_F1

   1% Fractile estimates for the distribution of volume of undiscovered associated-dissolved gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGAS_MEAN

   The mean estimate of volume of undiscovered associated-dissolved gas (in billions of cubic feet). (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F95

   95% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F90

   90% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F75

   75% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F50

   50% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F25

   25% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F10

   10% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F5

   5% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASL_F1

   1% Fractile estimates for the distribution of volume of undiscovered associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   ADGASLMEAN

   The mean estimate of volume of undiscovered associated gas liquids (in millions of barrels of natural gas liquids). (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F95

   95% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F90

   90% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F75

   75% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F50

   50% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F25

   25% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F10

   10% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F5

   5% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_F1

   1% Fractile estimates for the distribution of volume of undiscovered non-associated gas for the entire play (in billions of cubic feet) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGAS_MEAN

   The mean estimate of volume of undiscovered non-associated gas (in billions of cubic feet). (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F95

   95% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F90

   90% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F75

   75% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F50

   50% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F25

   25% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F10

   10% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F5

   5% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASL_F1

   1% Fractile estimates for the distribution of volume of undiscovered non-associated gas liquids for the entire play (in millions of barrels of natural gas liquids) (Source: USGS DDS-36)

   stored as a floating-point value

   NAGASLMEAN

   The mean estimate of volume of undiscovered non-associated gas liquids (in millions of barrels of natural gas liquids). (Source: USGS DDS-36)

   stored as a floating-point value

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • United States Geological Survey (USGS)

2. Who also contributed to the data set?

3. To whom should users address questions about the data?
   Christopher J. Schenk
   USGS
   Geologist
   U.S. Geological Survey MS939, Box25046
   Denver, Colorado 80225
   USA
   

   (303) 236-5796 (voice)
   schenk@usgs.gov
   

Why was the data set created?

The purpose of these files is to illustrate the geologic boundary of the play as defined for the 1995 U.S. National Assessment. The play was used as the fundamental assessment unit.

How was the data set created?

1. From what previous works were the data drawn?

   USGS DDS-30, Release 2 (source 1 of 3)

   U.S. Geological Survey, Gautier, D.L. (ed.), Dolton, G.L. (ed.), Takahashi, K.I. (ed.), and Varnes, K.L. (ed.), 1996, 1995 National Assessment of United States Oil and Gas Resources--Results, Methodology, and Supporting Data: U.S. Geological Survey Digital Data Series DDS-30.

   Type_of_Source_Media: CD-ROM

   Source_Contribution: U.S. National Oil and Gas Assessment

   USGS DDS-35 (source 2 of 3)

   U.S. Geological Survey, Beeman, W.R. (compiler), Obuch, R.C. (compiler), and Brewton, J.D. (compiler), 1996, Digital Map Data, Text, and Graphical Images in Support of the 1995 National Assessment of United States Oil and Gas Resources: U.S. Geological Survey Digital Data Series DDS-35.

   Type_of_Source_Media: CD-ROM

   Source_Contribution:

   digital map data in support of the 1995 U.S. National Oil and Gas Assessment

   USGS DDS-36 (source 3 of 3)

   U.S. Geological Survey, Charpentier, R.R. (compiler), Klett, T.R. (compiler), Obuch, R.C. (compiler), and Brewton, J.D. (compiler), 1996, Tabular Data, Text, and Graphical Images in Support of the 1995 National Assessment of United States Oil and Gas Resources: U.S. Geological Survey Digital Data Series DDS-36.

   Type_of_Source_Media: CD-ROM

   Source_Contribution:

   digital tabular data in support of the 1995 U.S. National Oil and Gas Assessment

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

   Date: Apr-2001 (process 1 of 1)

   We ran lins2cov.aml on the .lin files (from USGS DDS-35) to create the play coverages. The lins2cov.aml takes files from the NOGA 95 Spatial Data Disk (DDS-35), and reformats into Arc/Info Generate format (ASCII) files. They are then imported into ArcInfo coverages using the GENERATE command; subsequently they are cleaned to remove any potential overlap of polygons (using .000001 weed and fuzzy tolerances). Region/province/play numbers and names and the fractile estimates from the assessment of conventional undiscovered accumulations are appended to the file using lookup information acquired from tables on the NOGA 95 Tabular Information Disk (DDS-36). Plays with insufficient data or that were given low probability of containing an accumulation of minimum size, were not quantitatively assessed during the 1995 National Oil and Gas Assessment. Plays that were not quantitatively assessed contain only the attributes defining region/province/play names and numbers. The coverage is then converted to a shape file.

   Data sources used in this process:

   • USGS DDS-30, Release 2
   • USGS DDS-35
   • USGS DDS-36

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 main attribute for the play in this coverage is the play number, in which the first two digits represent the province number, and the next two digits represent the play number. Other attributes include the play name, and the region and province names and numbers. Also included are the output fractiles for the distribution of volume of undiscovered resource for the conventional plays (in millions of barrels of oil, billions of cubic feet of gas, or millions of barrels of natural gas liquids). Only accumulations greater than or equal to 1 million barrels of oil or 6 billion cubic feet of natural gas are included in this part of the assessment.

2. How accurate are the geographic locations?

   The play boundary was meant to delineate the gross boundary of the geologic elements that define the play.

3. How accurate are the heights or depths?

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

   The play was mapped in part on the data contained in the PI WHCS database for wells (1990 update), and the Nehring Significant Oil and Gas Field File (1992 update). Plays with insufficient data or that were given low probability of containing an accumulation of minimum size, were not quantitatively assessed during the 1995 National Oil and Gas Assessment. Plays that were not quantitatively assessed contain only the attributes defining region/province/play names and numbers.

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

   The play boundaries were defined on the basis of the surface and subsurface geology of the play, and the oil and gas production within the play. The province geologist was required to defend the geologic boundary of the play in a formal play review meeting.

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: none

1. Who distributes the data set? (Distributor 1 of 1)
   U.S. Geological Survey, Central Energy Team
   GIS Coordinator
   U.S. Geological Survey MS939, Box 25046
   Denver, Colorado 80225
   USA
   

   (303) 236-7773 (voice)
   lbiewick@usgs.gov
   

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

3. What legal disclaimers am I supposed to read?

   Although the data has been processed on the computer system at the U.S. Geological Survey, U.S. Department of the Interior, no warranty, expressed or implied, is made by the Geological Survey regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.

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

     Data format:	Assessment data for plays in format ArcView shapefile (version 1.0)
     Network links:	<http://energy.cr.usgs.gov/oilgas/noga/>

     Data format:	Assessment data for plays in format ArcInfo export (version 8.0)
     Network links:	<http://energy.cr.usgs.gov/oilgas/noga/>

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 17-Apr-2001
Last Reviewed: 30-Apr-2001

Metadata author:

U.S. Geological Survey, Central Energy Team
c/o Laura R.H. Biewick
GIS Coordinator
U.S. Geological Survey MS939, Box 25046
Denver, Colorado 80225
USA

(303) 236-7773 (voice)
lbiewick@usgs.gov

Metadata standard:

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