Method and apparatus for determining permeability of subsurface formations
US5463549A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1993 |
| Grant date | Oct 31, 1995 |
| Priority date | — |
| Expiry date | Oct 15, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/38
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Characteristics of invasion profiles exhibiting effects of gravity, and particularly their manifestations on resistivity logs of a plurality of different radial depths of investigation, are used to determine formation characteristics, including vertical permeability. One embodiment includes the following steps: suspending a logging tool in the borehole; producing a plurality of resistivity measurements, having respectively different radial depths of investigation, as the logging device is moved through the borehole, to obtain a plurality of resistivity logs; determining the presence of a buoyancy marker in the resistivity logs in a formation bed invaded with filtrate from the drilling mud, and the extent of the buoyancy marker; and determining permeability of the formations as a function of the extent of the buoyancy marker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.