Method and apparatus for measurement of borehole size and the resistivity of surrounding earth formations
US6384605B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 10, 1999 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Sep 10, 2019 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/085
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining the size or diameter of boreholes extending to a wide range of dimensions and/or the resistivity of the surrounding earth formations utilizing a well tool disposed in the borehole. The method involves generating model data representative of the well tool responses to different borehole diameters contrasted with formation and borehole fluid resistivity values, determining the borehole fluid resistivity, transmitting electromagnetic energy into the formation, measuring the energy shed back into the borehole at arbitrary sensor stations on the tool and generating resistivity signal data associated with the measured energy, and matching the signal data and the fluid resistivity against the modeled response data to determine the borehole caliper and/or formation resistivity. The apparatus forms part of a system for calculating a borehole caliper and/or the surrounding formation resistivity. The apparatus being coupled to a multi-sensor well tool and adapted to respond to signal data generated by the tool. The apparatus further adapted to receive the signal data; to receive a borehole fluid parameter; to store modeled well tool response data; and to…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.