Method to estimate cement acoustic wave speeds from data acquired by a cased hole ultrasonic cement evaluation tool
US9784875B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 2015 |
| Grant date | Oct 10, 2017 |
| Priority date | — |
| Expiry date | Dec 4, 2035 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/14
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Embodiments of the disclosure may include systems and methods for estimating an acoustic property of an annulus in a cement evaluation system. In one embodiment, a casing arrival signal is acquired at acoustic receivers a cement evaluation tool. A spectral amplitude ratio is calculated based on the casing arrival signal. The spectral amplitude ratio is scanned to detect and identify discontinuities. If discontinuities are detected, the frequency at the discontinuity may be used to estimate a wavespeed of the annulus. If discontinuities are not detected, attenuation dispersions are calculated and estimated, and an estimated wavespeed and parameters are updated until the calculated and estimated attenuation dispersions match.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.