Method for determining fracture closure pressure and fracture volume of a subsurface formation
US5050674A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 1990 |
| Grant date | Sep 24, 1991 |
| Priority date | — |
| Expiry date | Oct 9, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/006
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In one aspect of the present invention, a method is provided for determining the fracture closure pressure of a fractured formation. The method includes the steps of injecting a fracturing fluid into a subsurface formation to create a fracture, measuring the pressure response of the formation after injection has ceased, and determining the pressure at the onset of constant volume behavior as the fracture closure pressure. In another embodiment of the present invention, the fracture volume, leak-off volume and efficiency are determined by integrating the fracture closure rate over time, and then iterating with a fluid volume equation. Still another embodiment of the present invention determines the fracture volume, leak-off volume and efficiency by extrapolating the apparent system volume back to the moment when injection is stopped.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.