Method of acoustically detecting fractures in a borehole
US4799200A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1985 |
| Grant date | Jan 17, 1989 |
| Priority date | — |
| Expiry date | Oct 21, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
According to the method an acoustic transmitter/receiver tool is lowered in measured manner down a borehole. The tool possesses separate transducers for transmitting and receiving sound waves and includes at least one pair of spaced apart transmitter and receiver spacing. As it is lowered, the tool is caused to repetitively transmit sound waves and on each occasion the waveforms of the echoes received by the tool are recorded in relation to the spacing. Fractures are detected by processing portions of the waveforms which are representative of at least one of two different local effects corresponding to fractures, which effects are amplitude peaks due to a local increase in acoustic coupling, and criss-cross patterns due to mode conversion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.