Arthur J Thompson

US Patent:

46482610, Mar 10, 1987

Filed:

Nov 12, 1985

Appl. No.:

6/797107

Inventors:

Arthur H. Thompson - Spring TX
Alan J. Katz - Houston TX

Assignee:

Exxon Production Research Co. - Houston TX

International Classification:

G01N 1508

US Classification:

73 38

Abstract:

A method for determining pore-dependent properties, such as electrical conductivity and absolute permeability, of a porous sample by use of capillary pressure measurements. Capillary pressure data are obtained by performing nonwetting fluid intrusion measurements on a sample. The lowest applied pressure at which the intruding fluid forms a connected path spanning the sample (the "threshold capillary pressure") is determined. The sample's conductivity or absolute permeability, or both, may be determined in a preferred embodiment from the characteristic pore diameter corresponding to the threshold capillary pressure, an other parameters extracted from the measured capillary pressure data. The invention does not require use of any arbitrary, empirically adjustable parameter to predict conductivity or permeability. The method may be performed to characterize small samples of porous rock such as those obtained during borehold drilling operations.