Pulsed neutron porosity logging system
US4122340A · kind A · utility
21Cited by
4References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1977 |
| Grant date | Oct 24, 1978 |
| Priority date | — |
| Expiry date | Apr 20, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/105
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved pulsed neutron porosity logging system is provided in the present invention. A logging tool provided with a 14 MEV pulsed neutron source, an epithermal neutron detector, and a fast neutron detector is moved through a borehole. Repetitive bursts of neutrons irradiate the earth formations and, during the bursts, the fast neutron population is sampled. During the interval between bursts the epithermal neutron population is sampled along with background gamma radiation due to lingering thermal neutrons. The fast and epithermal neutron population measurements are combined to provide a measurement of formation porosity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.