Methods and apparatus for borehole measurement of formation stress
US5517854A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1994 |
| Grant date | May 21, 1996 |
| Priority date | — |
| Expiry date | Apr 29, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/008
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A modular sonde may be configured in various ways for measurements in open or cased boreholes. The sonde is conveyed on an electric wireline with or without a coiled tubing for conveying hydraulic energy from the surface. Modules common to the configurations include telemetry electronics, orientation, hydraulic energy accumulator, fluid chambers, hydraulic power, pumpout, and flow control. Each configuration has a stress/rheology module suited to the borehole situation. An open-hole sonde configuration has a stress/rheology module with an instrumented, inflatable packer module, an orienting module, and a probe module. A second open-hole sonde configuration has a stress/rheology module with an instrumented straddle-packer assembly. A cased-hole sonde configuration has a gunblock assembly, a gunblock orienting module hydraulics for formation pretest and hydraulics for stressing the formation to obtain data related to formation stress characteristics. A second cased-hole sonde configuration has a straddle-packer assembly, a casing perforation device in the straddle interval, and hydraulics for stressing the formation to obtain data related to formation stress characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.