Estimation of horizontal stresses and nonlinear constants in anisotropic formations such as interbedded carbonate layers in organic-shale reservoirs
US11015443B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2017 |
| Grant date | May 25, 2021 |
| Priority date | — |
| Expiry date | Jul 21, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V2210/626
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and systems are provided that identify relatively large anisotropic horizontal stresses in a formation based on (i) azimuthal variations in the compressional and shear slownesses or velocities of the formation measured from ultrasonic data acquired by at least one acoustic logging tool as well as (ii) cross-dipole dispersions of the formation measured from sonic data acquired by the at least one acoustic logging tool. In addition, the azimuthal variations in the compressional and shear slownesses or velocities of the formation and dipole flexural dispersions of the formation can be jointly inverted to obtain the elastic properties of the rock of the formation in terms of linear and nonlinear constants and the magnitude of maximum horizontal stress of the formation. A workflow for estimating the magnitude of the maximum horizontal stress can employ estimates of certain formation properties, such as overburden stress, magnitude of minimum horizontal stress, and pore pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.