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FORSPAN Model Users Guide

By T.R. Klett, and Ronald R. Charpentier


U.S. Geological Survey Open-File Report 03-354

Version 1.0
The USGS FORSPAN model is designed for the assessment of continuous accumulations of crude oil, natural gas, and natural gas liquids (collectively called petroleum). Continuous (also called “unconventional”) accumulations have large spatial dimensions and lack well defined down-dip petroleum/water contacts. Oil and natural gas therefore are not localized by buoyancy in water in these accumulations. Continuous accumulations include “tight gas reservoirs,” coalbed gas, oil and gas in shale, oil and gas in chalk, and shallow biogenic gas.

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OFR-03-354 PDF file (1.79 MB)

Basic input-data form for the FORSPAN model
Data worksheet
Completed FORSPAN basic input data form

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