Method for determining formation density and formation photo-electric factor with a multi-detector-gamma-ray tool
US5912460A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1997 |
| Grant date | Jun 15, 1999 |
| Priority date | — |
| Expiry date | Mar 6, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/125
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An advanced method for determining formation density in an array-detector density tool uses three or more detectors to yield an improved accuracy and precision of the formation density measurement even in the presence of a large standoff between the tool and the formation. A more accurate photoelectric factor is determined through a new single detector algorithm. Use of the information on the photoelectric effect and the density from the three detectors allows the measurement of a photoelectric effect compensated for stand off and the photoelectric factor of the mudcake. The use of the multi-detector density answers allows for a consistency check and therefore a much improved quality control of the density measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.