Skip to main content
Log in

Oil and gas in offshore tracts: Bias in estimates of reserves

  • Published:
Journal of the International Association for Mathematical Geology Aims and scope Submit manuscript

Abstract

Two independent data sets show that current means of estimating reserves of oil and gas in offshore fields are biased. The bias which is established here is that small fields (with less than about 10 million barrels of oil equivalent) are overestimated, and larger fields (at least up to 200 MMBOE) are underestimated. This systematic bias occurs with or without a significant overall bias, and in addition to a large scatter. Because bias (as opposed to scatter) has serious implications for national energy policy, and in particular for conduct of offshore lease sales, these results indicate that evaluation methods should be revised, or that ad hoc adjustments (based on historical data) should be applied.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Davis, J. C. and Harbaugh, J. W., 1980, Oil and gas in offshore tracts: Inexactness of resource estimates prior to drilling:Science, v. 201 (4460), p. 1047.

    Google Scholar 

  • Guest, P. M., 1961, Numerical methods of curve fitting: Cambridge University Press, London.

    Google Scholar 

  • Halperin, M., 1964, Interval estimation in linear regression when both variables are subject to error:Jour. Amer. Stat. Assoc., v. 59, p. 1112.

    Google Scholar 

  • National Research Council, 1978, The potential for increasing production of natural gas from existing fields in the near term; report of committee on gas production opportunities: NRC, National Academy of Science, Washington, D.C.

    Google Scholar 

  • Uman, M. F., James, W. R., and Tomlinson, H. A., 1979, Oil and gas in offshore tracts: Estimates before and after drilling:Science, v. 204, p. 489.

    Google Scholar 

  • Uman, M. F., James, W. R., and Tomlinson, H. R., 1980, Reply (to Davis and Harbough):Science, v. 209 (4460), p. 1048.

    Google Scholar 

  • United States Geological Survey, 1976, Principles of the mineral resource classification system of the U.S. Bureau of Mines and U.S. Geological Survey: Bulletin 1450-A, U.S. Geological Survey, Washington, D.C.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Thomsen, L.A., Joggerst, M. Oil and gas in offshore tracts: Bias in estimates of reserves. Mathematical Geology 17, 353–365 (1985). https://doi.org/10.1007/BF01032926

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01032926

Key words

Navigation