Apparatus and methods for determining gas saturation and porosity of a formation penetrated by a gas filled or liquid filled borehole
US6207953A · kind A · utility
Inventor
Key dates
| Filing date | Apr 24, 1998 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Apr 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V5/104
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus are disclosed for determining gas saturation, liquid saturation, porosity and density of earth formations penetrated by a well borehole. Determinations are made from measures of fast neutron and inelastic scatter gamma radiation induced by a pulsed, fast neutron source. The system preferably uses two detectors axially spaced from the neutron source. One detector is preferably a scintillation detector responsive to gamma radiation, and a second detector is preferably an organic scintillator responsive to both neutron and gamma radiation. The system can be operated in cased boreholes which are filled with either gas or liquid. Techniques for correcting all measurements for borehole conditions are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.