Borehole measurements using a fast and high energy resolution gamma ray detector assembly
US7999220B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 30, 2008 |
| Grant date | Aug 16, 2011 |
| Priority date | — |
| Expiry date | Nov 14, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/104
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gamma ray detector assembly for a borehole logging system that requires the measure of gamma radiation with optimized gamma ray energy resolution and with fast emission times required to obtain meaningful measurements in high radiation fields. The detector assembly comprises a lanthanum bromide (LaBr3) scintillation crystal and a digital spectrometer that cooperates with the crystal to maximize pulse processing throughput by digital filtering and digital pile-up inspection of the pulses. The detector assembly is capable of digital pulse measurement and digital pile-up inspection with dead-time less than 600 nanoseconds per event. Pulse height can be accurately measured (corrected for pile-up effects) for 2 pulses separated by as little as 150 nanoseconds. Although the invention is applicable to virtually any borehole logging methodology that uses the measure of gamma radiation in harsh borehole conditions, the invention is particularly applicable to carbon/oxygen logging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.