Identifying and visually presenting formation slowness based on low-frequency dispersion asymptotes
US10775525B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2017 |
| Grant date | Sep 15, 2020 |
| Priority date | — |
| Expiry date | Jan 31, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V2210/74
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Techniques for estimating and visually presenting formation slowness are disclosed herein. The techniques include receiving acoustic signal responses from adjacent formations at a plurality of depths in a borehole environment, mapping a distribution of the acoustic signal responses at each depth according to slowness and a frequency values, determining at least one confidence interval to define a coherence threshold for the distribution of the acoustic signal responses at each depth, generating a variable density log for each depth based on the distribution of acoustic signals responses that satisfy the confidence interval for one or more frequency ranges, determining a formation slowness value for each depth based on the variable density log for the each depth, and presenting a semblance map that includes a slowness axis, a depth axis, the formation slowness value for each depth, and at least a portion of the distribution of acoustic signal responses at each depth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.