Method for determining hydrocarbon/water contact level for oil and gas wells
US5621169A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1996 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Sep 10, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/008
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for predicting the hydrocarbon/water contact level for oil and gas wells which relates porosity .phi., water saturation S.sub.w, air permeability k.sub.a, and capillary pressure P.sub.c. Such contact level may be estimated without actual capillary pressure measurements. The method relies on a worldwide correlation of permeability and porosity to a function of capillary pressure. The hydrocarbon/water contact levels are predicted through regression analysis using porosity .phi., water saturation S.sub.w, and air permeability k.sub.a from well log and core analysis information. Relationships used in this method include ##EQU1## where P.sub.c is mercury capillary pressure, F.sub.g is pore geometrical factor, S.sub.w is water saturation, P.sub.d is mercury displacement pressure, k.sub.a is air permeability, and .phi. is porosity. The constants set forth in equations (b) and (c) above may be adjusted to fit measured data from rock samples within the reservoir.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.