Method and apparatus for acoustic well logging
US4685091A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1984 |
| Grant date | Aug 4, 1987 |
| Priority date | — |
| Expiry date | May 10, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S367/912
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method and apparatus for acoustic wave generation and transmission into a subsurface earth formation. A logging sonde adapted to be suspended in a borehole within the formation houses a generator means for simultaneously generating a plurality of acoustic waves traveling in the direction of and spaced substantially evenly about the logitudinal axis of the sonde. An acoustic energy reflector means within the housing reflects the waves radially outwards of the axis and into the formation at angles generally perpendicular to the axis. Detectors within the housing spaced longitudinally from the generator and reflector detect acoustic energy in the formation resulting from the reflected waves. In a preferred embodiment, the generator means comprises four cylindrical magnetostrictively energized elements disposed about the central axis of the sonde, each having an axis parallel to the central axis, so that the four axes of the elements, when viewed in the direction of the central axis, define four corners of a square. The elements are designed so that upon energization, a given element vibrates longitudinally out of phase relative to the two elements adjacent thereto, vibration of the fo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.