Method and apparatus for measuring the thermal neutron absorption rate in earth formations
US4385235A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 17, 1980 |
| Grant date | May 24, 1983 |
| Priority date | — |
| Expiry date | Nov 17, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/108
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Circuitry is provided for establishing the points in time at which radiation is detected following neutron bursts in pulsed neutron logging. Means are provided to generate a signal indicative of the average time measurement of a predetermined number of detected pulses within a detection gate interval. A first counter circuit establishes a time position for each detected pulse within the detection interval. The time measurement signal is loaded into a down counter which transfers the individual time to a third accumulator circuit where the times signals for a predetermined number of detected pulses are compiled. The total time signal is averaged by dividing the accumulated value by the predetermined number of processed pulses. The resultant value is used to establish the macroscopic thermal neutron capture cross-section of the formation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.