Method and apparatus for determining elemental concentrations for .gamma. r a
US5471057A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 9, 1994 |
| Grant date | Nov 28, 1995 |
| Priority date | — |
| Expiry date | Sep 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/101
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining the elemental concentrations in an underground formation by irradiating the formation with neutrons, detecting the .gamma. ray spectrum arising from neutron capture by the formation and analyzing the spectrum to determine elemental concentrations. This method avoids the need for activation measurements or natural radiation measurements and which is made possible by modifying the detected yield of iron (Fe) in the spectrum to compensate for the absence of aluminum (Al) and for the absence of potassium (K) when not measured directly. Apparatus for performing this method can comprise a neutron source, such as a broad energy chemical source, e.g. AmBe, or a pulsed accelerator source, a .gamma. ray detector for detecting capture .gamma. rays and means for analyzing the spectra detected by the detector for determining the elemental concentrations in the formation. This apparatus does not require an activation source nor does it require natural radiation or activation detectors and analysis circuitry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.