Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources
Abstract
Methods and apparatus are provided for measuring the acoustically modulated electronic properties of geological formations and cement layers adjacent to cased boreholes. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. Voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the leakage current conducted into formation in the vicinity of those electrodes. Simultaneously subjecting the casing and formation to an acoustic source acoustically modulates the leakage current measured thereby providing a measure of the acoustically modulated electronic properties of the adjacent formation. Similarly, methods and apparatus are also described which measure the leakage current into formation while simultaneously subjecting the casing to an applied magnetic field which therefore allows measurement of the magnetically modulated electronic properties of the casing and the adjacent formation. 9 figures.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 7083345
- Patent Number(s):
- 5043669
- Application Number:
- CNN: 5088-212-1664; PPN: US 7-438268
- Assignee:
- Para Magnetic Logging, Inc., Woodinville, WA (United States)
- DOE Contract Number:
- FG06-84ER13294; FG22-88BC14243
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 16 Nov 1989
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION; 58 GEOSCIENCES; RESISTIVITY LOGGING; WELL LOGGING EQUIPMENT; DESIGN; OPERATION; ACOUSTICS; ELECTRICAL PROPERTIES; MAGNETIC FIELDS; MODULATION; RESERVOIR ROCK; WELL CASINGS; WELLS; ELECTRIC LOGGING; EQUIPMENT; PHYSICAL PROPERTIES; WELL LOGGING; 440400* - Well Logging Instrumentation; 580000 - Geosciences
Citation Formats
Vail, III, W B. Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources. United States: N. p., 1991.
Web.
Vail, III, W B. Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources. United States.
Vail, III, W B. Tue .
"Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources". United States.
@article{osti_7083345,
title = {Methods and apparatus for measurement of the resistivity of geological formations from within cased wells in presence of acoustic and magnetic energy sources},
author = {Vail, III, W B},
abstractNote = {Methods and apparatus are provided for measuring the acoustically modulated electronic properties of geological formations and cement layers adjacent to cased boreholes. Current is passed from an electrode in electrical contact with the interior of the borehole casing to an electrode on the surface of the earth. Voltage measuring electrodes in electrical contact with the interior of the casing measure the voltage at various points thereon. The voltage differences between discrete pairs of the voltage measuring electrodes provide a measurement of the leakage current conducted into formation in the vicinity of those electrodes. Simultaneously subjecting the casing and formation to an acoustic source acoustically modulates the leakage current measured thereby providing a measure of the acoustically modulated electronic properties of the adjacent formation. Similarly, methods and apparatus are also described which measure the leakage current into formation while simultaneously subjecting the casing to an applied magnetic field which therefore allows measurement of the magnetically modulated electronic properties of the casing and the adjacent formation. 9 figures.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1991},
month = {8}
}