Method for simultaneous measurement of borehole and formation neutron lifetimes
US4424444A · kind A · utility
31Cited by
6References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 1, 1982 |
| Grant date | Jan 3, 1984 |
| Priority date | — |
| Expiry date | Jul 1, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2223/616
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention concerns methods for measuring simultaneously the formation and borehole components of thermal neutron lifetime as decay time. The borehole and formation are irradiated with pulsed 14 MEV neutrons. During the interval between neutron pulses the capture gamma radiation is measured in at least four, non-overlapping, contiguous time gates. A background radiation measurement is also periodically made. The background corrected capture gamma radiation measurements are combined to derive simultaneously, the formation and borehole neutron lifetime components which are then recorded as a function of borehole depth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.