Method and an apparatus for detecting fracture with significant residual width from previous treatments
US7774140B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 30, 2004 |
| Grant date | Aug 10, 2010 |
| Priority date | — |
| Expiry date | Jun 10, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/008
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A refracture-candidate diagnostic test is an injection of compressible or slightly compressible fluid at pressures in excess of minimum in-situ stress and formation fracture pressure with pressure decline following injection test recorded to detect a fracture retaining residual width from previous stimulation treatments. The diagnostic consists of small volume injections with injection time being a small fraction of time required for compressible or slightly compressible reservoir fluid to exhibit pseudoradial flow. The fracture-injection portion of a test can be considered as occurring instantaneously. Data measurements are transformed into a constant rate equivalent pressure transformation to obtain adjusted pressures or adjusted pseudovariables which are analyzed to identify dual unit-slope before and after closure periods confirming a residual retaining width.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.