Patent · US Expired

Method and apparatus for determining formation pressure

US5789669A · kind A · utility

41Cited by
4References
20Claims
0Family size

Inventor

Key dates

Filing dateAug 13, 1997
Grant dateAug 4, 1998
Priority date
Expiry dateAug 13, 2017

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B49/008
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A method is disclosed for determining true formation pressure in formations surrounding a fluid-containing borehole having a mudcake on the surface thereof, including the following steps: with the pressure in the borehole at a first measured borehole pressure, measuring, as a first probe pressure, the pressure in the formation adjacent the mudcake; with the pressure in the borehole at a second measured borehole pressure, measuring, as a second probe pressure, the pressure in the formation adjacent the mudcake; and deriving the true formation pressure from the first and second measured borehole pressures and the first and second probe pressures.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.