Method and apparatus for geophysical formation evaluation measurements behind casing
US11994642B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 2019 |
| Grant date | May 28, 2024 |
| Priority date | — |
| Expiry date | May 5, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V2210/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus, methods, and systems for determining acoustic velocity behind casing or tubing in a subterranean wellbore. A method may include obtaining a plurality of waveform data sets corresponding to a plurality of propagation path regimes and obtaining a total wavefield across the receiver array. The method may also include determining a Green's function representing each of the plurality of propagation path regimes and determining a noise wavefield by convolving the Green's functions and a known transmitted pressure signal corresponding to the plurality of waveform data sets. The method may also include generating a reduced-noise wavefield by subtracting the noise wavefield from the total wavefield and estimating the acoustic velocity of a formation behind the casing or tubing from the reduce-noise wavefield.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.