Combining inelastic and capture gamma ray spectroscopy for determining formation elemental
US10429540B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 19, 2012 |
| Grant date | Oct 1, 2019 |
| Priority date | — |
| Expiry date | Dec 30, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/101
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining weight fractions of a plurality of elements in a subsurface formation penetrated by a wellbore includes determining weight fractions of a first plurality of elements using measurements of capture gamma rays made in the wellbore. The capture gamma rays result from bombardment of the formations with high energy neutrons. A weight fraction of a second plurality of elements is determined using measurements of inelastic gamma rays made in the wellbore resulting from bombardment of the formations with high energy neutrons. The weight fraction for the second plurality is determined by setting a transformation factor for those elements common to both the first and second plurality to result in a statistically equivalent weight fraction for the common elements as determined for the first plurality of elements. Weight fractions of elements in the second plurality not common to the first plurality of elements is determined using the set transformation factor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.