Combination of epithermal and inelastic neutron scattering methods to locate coal and oil shale zones
US3947683A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1974 |
| Grant date | Mar 30, 1976 |
| Priority date | — |
| Expiry date | Feb 15, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/102
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pulsed source of high energy neutrons is used to irradiate the earth formations in the vicinity of a well borehole. Gamma rays produced by the inelastic scattering of the fast neutrons are observed in four energy regions of the gamma ray energy spectrum corresponding to the inelastic scattering of neutrons by carbon, oxygen, silicon and calcium. Signals representative of the carbon/oxygen, calcium/silicon and carbon plus oxygen gamma rays observed are developed. By appropriately combining these signals with a separately derived hydrogen index log the quality of coal bearing formations or oil shale regions penetrated by the borehole may be determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.