Method for estimating permeability of earth formations by processing stoneley waves from an acoustic wellbore logging instrument
US5784333A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1997 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | May 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining the permeability of earth formations penetrated by a wellbore from acoustic signals measured by an acoustic wellbore logging instrument. The method includes separating components from the measured acoustic signals which represent Stoneley waves propagating through the earth formations. Signals representing Stoneley waves propagating through the same earth formations are synthesized. The separated acoustic signal components and the synthesized Stoneley wave signals are compared. The permeability is determined from differences between the synthesized Stoneley wave signals and the separated acoustic signal components. In a preferred embodiment, the step of calculating the permeability includes inversion processing a wave center frequency shift and a wave travel time delay with respect to the permeability of the earth formations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.