Method and apparatus for multipole acoustic logging
US4951267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1986 |
| Grant date | Aug 21, 1990 |
| Priority date | — |
| Expiry date | Oct 15, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/44
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for shear wave borehole logging has a source section 30, a spacer section 32, a detector section 34 and a coupling section 36, adjacent sections being linked by isolation joints 38. The source section 30 has a slotted steel housing 48 containing a source 42 with two transducers 44a/44b and 44c/44d each arranged to produce acoustic radiation with a dipole radiation pattern. The transducers are oriented so that their radiation patterns are transverse to one another and to the borehole axis. The detector section 34 also has a slotted steel housing 80 and contains six detectors 82 each with two transducers 84a/84b and 84c/84d arranged similarly to the source transducers. The isolation joint 38 between adjacent sections comprises lengths of steel wire 76 secured at each end to one of the sonde sections and bridging a gap between the sections. In use each of the source transducers is energized in turn as the apparatus is drawn up the borehole, and the waveforms of signals received by the twelve detector transducers are digitized and recorded. Various analyses of the recordings enable the formation shear slowness to be derived, even in `slow` formations, and permit information t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.