Carbonates and Evaporites

, Volume 16, Issue 1, pp 71–92 | Cite as

Petrophysical facies of the ordovician red river formation, Williston basin, USA

  • Lillian Hess Tanguay
  • Gerald M. FriedmanEmail author


A petrophysical facies is a mappable rock unit of similar petrophysical characteristics, imparted by the depositional and diagenetic environment. Capillary-pressure curves are the basis for delineating a petrophysical facies.

Important parameters that affect the shape of a capillary-pressure curve are sorting of the pore-throat size distribution, the maximum threshold-entry radius, and percent recovery efficiency. Curve types based on these parameters are spatially clustered both laterally and vertically within the Red River Formation. The ordering of petrophysical facies, vertically up-hole, is related to the maximum threshold-entry radius which range from very small radii ‘A’ to very large radii ‘F’, with ‘C’ and ‘D’ of moderate size as defined in the construction of curve type designation. In the Red River depositional sequences, petrophysical facies are ordered by ‘B-C-D-C-B’, where either ‘A’, ‘E’, ‘F’, or PS is found at the bottom or top of the sequence, defining a sandwiched sequence of pore throats with the optimum reservoir facies in the center.

The maximum-threshold entry radius, apparent porosity, and recovery efficiency are logged for each lithologic unit. Large maximum threshold-entry radii are associated with poorly sorted pore-throat size distributions and/or little to no porosity. Recovery efficiency is only meaningful for dolostones with moderate to high porosity.


Dolostone Anhydrite Recovery Efficiency Pore Throat Mercury Porosimetry 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. CLEMENT, J.H., 1978, Depositional sequences and characteristics of Ordovician Red River producing zones, Pennel Field, Cedar Creek Anticline, Fallon County, Montana (Abstract)in Montana Geological Society Guidebook: Williston Basin Symposium, p. 97.Google Scholar
  2. DULLIEN, F.A.L. and DHAWAN, G.K., 1974, Characterization of pore structure by a combination of quantitative photomicrography and mercury porosimetry:Journal of Colloid and Interface Science, v. 47, p. 337–349.CrossRefGoogle Scholar
  3. DULLIEN, F.A.L. and DHAWAN, G.K., 1975, New network permeability model of porous media:American Institute of Chemical Engineering Journal, v. 21, p. 299–307.CrossRefGoogle Scholar
  4. FRIEDMAN, G.M., RUZYLA, K., and REECKMANN, A., 1981, Effects of porosity type, pore geometry and diagenetic history on Tertiary recovery of petroleum from carbonate reservoirs: U. S. Department of Commerce, National Technical Information Service, 217 p.Google Scholar
  5. RUZYLA, K., 1980, The relationship of diagenesis to porosity development and pore geometry in the Red River Formation (Upper Ordovician), Cabin Creek Field, Montana: Unpublished Doctoral Thesis, Rensselaer Polytechnic Institute, Troy, New York, 200 p.Google Scholar
  6. RUZYLA, K. and FRIEDMAN, G.M., 1982, Geological heterogeneities important to future enhanced recovery in Carbonate reservoirs of Upper Ordovician Red River Formation at Cabin Creek Field, Montana:Society of Petroleum Engineers Journal, v. 22, p. 429–444.CrossRefGoogle Scholar
  7. RUZYLA, K. and FRIEDMAN, G.M., 1985, Factors controlling porosity in dolomite reservoirs of the Ordovician Red River Formation, Cabin Creek Field, Montana, in Carbonate Petroleum Reservoirs: Springer-Verlag, New York, p. 40–58.Google Scholar
  8. TANGUAY, L.H. and FRIEDMAN, G.M., 2001, Petrophysical characteristics and facies of Carbonate reservoirs: the Red River Formation (Ordovician), Williston Basin:American Association of Petroleum Geologists Bulletin, v. 85, p. 491–523.Google Scholar
  9. WARDLAW, N.C., 1976, Pore geometry of carbonate rocks as revealed by pore casts and capillary pressure:American Association of Petroleum Geologists Bulletin, v. 60, p. 245–257.Google Scholar

Copyright information

© Springer 2001

Authors and Affiliations

  1. 1.Department of Earth and Environmental ScienceC.W. Post Campus of Long Island UniversityBrookville
  2. 2.Department of GeologyBrooklyn College and Graduate School of the City University of New YorkBrooklyn
  3. 3.Northeastern Science Foundation, Inc., affiliated with Brooklyn CollegeRensselaer Center of Applied GeologyTroy

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