Carbonate permeability
AssigneeSchlumberger Technology Corporation
InventorMichael M. Herron
Life of this patent
Estimating the term…
Abstract
A modification to the Coates-Timur relationship to produce a more coherent relationship applicable to carbonate formations is disclosed. In this method, permeability may be determined using porosity and the ratio of bound fluid volume to (1—bound fluid volume). This method also allows for improved estimation of irreducible water saturation of a carbonate formation using the ratio of kc and (eφf+kc). Likewise, the bound fluid volume of a carbonate formation may be determined using the ratio of φkc and (eφf+kc). In these relationships, e, x, and f are constants according to the following relationships e=xc, f=bc+1, x is between 1 and 100 mD (preferably 10 mD).
Claims19
A method to determine the permeability of a carbonate formation, comprising:
- a. obtaining data representative of said carbonate formation;
- b. determining the porosity (φ) of said carbonate formation from said data and at least one of the group consisting of bound fluid volume (BFV) and irreducible water saturation (Swirr) of said carbonate formation from said data;
- and
- c. estimating the permeability (k) of said carbonate formation using the porosity and the ratio of (1—BFV) and BFV.
A method to determine the irreducible water saturation of a carbonate formation, comprising:
- a. obtaining data representative of said carbonate formation;
- b. determining the porosity (φ) and permeability (k) of said carbonate formation from said data;
- and
- c. estimating the irreducible water saturation of said carbonate formation using the ratio of kc and (eφf+kc), wherein c, e, and f are constants.
A method to determine the bound fluid volume of a carbonate formation, comprising:
- a. obtaining data representative of said carbonate formation;
- b. determining the porosity (φ) and permeability (k) of said carbonate formation from said data;
- and
- c. estimating the bound fluid volume of said carbonate formation using the ratio of φkc and (eφf+kc), wherein c, e, and f are constants.
Dependencies are inferred from the claim text.