Well logging apparatus and method for determining formation resistivity at a shallow and a deep depth
US4899112A · kind A · utility
159Cited by
19References
67Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1987 |
| Grant date | Feb 6, 1990 |
| Priority date | — |
| Expiry date | Oct 30, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Well logging techniques and apparatus are disclosed for determining formation resistivity at different radial depths of investigation and with greater accuracy than prior techniques, for determining the existence, locations and properties of beds and caves, and for determining changes in the size of a borehole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.