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Open-File Report 2007–1404

Database for Assessment Unit-Scale Analogs (Exclusive of the United States)

By Ronald R. Charpentier, T.R. Klett, and Emil D. Attanasi

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Open-File Report
2007-1404 PDF (3.6 MB)

This publication presents a database of geologic analogs useful for the assessment of undiscovered oil and gas resources. Particularly in frontier areas, where few oil and gas fields have been discovered, assessment methods such as discovery process models may not be usable. In such cases, comparison of the assessment area to geologically similar but more maturely explored areas may be more appropriate. This analog database consists of 246 assessment units, based on the U.S. Geological Survey 2000 World Petroleum Assessment. Besides geologic data to facilitate comparisons, the database includes data pertaining to numbers and sizes of oil and gas fields and the properties of their produced fluids.

Version 1.0

Posted January 2008

  • Downloads Directory
  • Database files for download. Please refer to Appendix 2 within the report for more information.

Suggested citation:

Charpentier, R.R., Klett, T.R., and Attanasi, E.D., 2008, Database for assessment unit-scale analogs (exclusive of the United States): U.S. Geological Survey Open-File Report 2007–1404, 61 p.




Sources of Data

Sizes of Discovered Fields

2000 World Petroleum Assessment


Small-Field Extrapolation

Additional Calculations

Global Distributions

Use of Database

Classification Variables

Methods of Searching

Utility Variables

Variables Related to Number of Fields

Variables Related to Field Size Distribution

Variables Related to Maturity of Exploration

Variables Related to Coproduct Ratios

Variables Related to Ancillary Data

Data Analysis Tools

Distributions for Small Analog Sets

Distributions for Large Analog Sets

Example of Use with USGS Assessment Methodology

Selection of Analogs

Numbers of Fields

Sizes of Fields

Coproduct Ratios


Appendix 1. 1995 Methodology for Small-Field Extrapolation

For the Pareto Distribution

Relation Between Pareto and Log-Geometric Distributions

Changes to Small-Field Extrapolation Methodology

Sensistivity Tests

Unresolved Issues

Appendix 2. Database Files

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