Method for analyzing cement integrity in cased wells using sonic logging
US10705056B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2016 |
| Grant date | Jul 7, 2020 |
| Priority date | — |
| Expiry date | May 27, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2636
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods are provided for identifying a cementation status of a multi-string cased wellbore utilizing sonic tools with monopole and/or dipole transmitters and with an array of sonic receivers axially displaced from the transmitter(s). The sonic tool is used to record waveforms. The waveforms are then processed to generate slowness and/or attenuation dispersions. The slowness and/or attenuation dispersions are projected onto a slowness and/or attenuation axis, and the results are compared to a data set of projected slowness and/or attenuation dispersions representing a plurality of different multi-string cased wellbore cement status scenarios in order to select the scenario most closely associated with the results. The presence or lack of eccentering of a casing is similarly obtained where the data set includes projected dispersions representing properly centered and ec-centered casings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.