Methods for determining in situ shale strengths, elastic properties, pore pressures, formation stresses, and drilling fluid parameters
US5205164A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1990 |
| Grant date | Apr 27, 1993 |
| Priority date | — |
| Expiry date | Aug 31, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining drilling fluid density for stabilizing a wellbore including obtaining shale cuttings from a wellbore. In one embodiment of a method according to this invention, shale cuttings are obtained from a wellbore and their index properties, including but not limited to surface area, is measured; mean effective stress around the wellbore is calculated using the geostatic overburden in situ stress, the field pore pressure, and the total stress around the wellbore; the in situ shale strength is determined using a correlation between surface area, mean effective stress and shale strength; and drilling fluid density is determined using the shale strength. Methods for determining in situ shale strengths, elastic properties, pore pressures, and formation stresses of low permeability rocks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.