Depth-dependent mud density determination and processing for horizontal shear slowness in vertical transverse isotropy environment using full-waveform sonic data
US10989824B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2019 |
| Grant date | Apr 27, 2021 |
| Priority date | — |
| Expiry date | Oct 26, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V2210/6224
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An acoustic logging method that may comprise acquiring waveforms for multiple acoustic wave modes as a function of tool position in a borehole; deriving position-dependent mode dispersion curves from the waveforms; accessing a computed library of dispersion curves for a vertical shear slowness (s) and a Thomsen gamma (γ) of a given acoustic wave mode as a function of frequency; interpolating dispersion curves in the computed library to an assumed known compressional wave slowness, a borehole radius, a formation density, a mud density, and a mud slowness; computing an adaptive weight; and inverting dispersion curve modes jointly for a shear wave anisotropy, a vertical shear wave slowness, an inverted mud slowness, and an inverted mud density as a function of depth. An acoustic logging system may comprise a logging tool, a conveyance attached to the logging tool, at least one sensor, and at least one processor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.