Three-component borehole wall-locking seismic detector
Abstract
A seismic detector for boreholes is described that has an accelerometer sensor block for sensing vibrations in geologic formations of the earth. The density of the seismic detector is approximately matched to the density of the formations in which the detector is utilized. A simple compass is used to orient the seismic detector. A large surface area shoe having a radius approximately equal to the radius of the borehole in which the seismic detector is located may be pushed against the side of the borehole by actuating cylinders contained in the seismic detector. Hydraulic drive of the cylinders is provided external to the detector. By using the large surface area wall-locking shoe, force holding the seismic detector in place is distributed over a larger area of the borehole wall thereby eliminating concentrated stresses. Borehole wall-locking forces up to ten times the weight of the seismic detector can be applied thereby ensuring maximum detection frequency response up to 2,000 hertz using accelerometer sensors in a triaxial array within the seismic detector.
- Inventors:
-
- Helotes, TX
- Issue Date:
- Research Org.:
- Southwest Research Institute, San Antonio, TX (United States)
- OSTI Identifier:
- 869235
- Patent Number(s):
- 5302782
- Assignee:
- Southwest Research Institute (San Antonio, TX)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01V - GEOPHYSICS
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- DOE Contract Number:
- AC22-89BC14473
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- three-component; borehole; wall-locking; seismic; detector; boreholes; described; accelerometer; sensor; block; sensing; vibrations; geologic; formations; earth; density; approximately; matched; utilized; simple; compass; orient; surface; shoe; radius; equal; located; pushed; actuating; cylinders; contained; hydraulic; drive; provided; external; force; holding; distributed; larger; wall; eliminating; concentrated; stresses; forces; times; weight; applied; ensuring; maximum; detection; frequency; response; 000; hertz; sensors; triaxial; array; sensor block; hydraulic drive; approximately equal; seismic detector; borehole wall; sensing vibrations; frequency response; geologic formations; axial array; /181/
Citation Formats
Owen, Thomas E. Three-component borehole wall-locking seismic detector. United States: N. p., 1994.
Web.
Owen, Thomas E. Three-component borehole wall-locking seismic detector. United States.
Owen, Thomas E. Sat .
"Three-component borehole wall-locking seismic detector". United States. https://www.osti.gov/servlets/purl/869235.
@article{osti_869235,
title = {Three-component borehole wall-locking seismic detector},
author = {Owen, Thomas E},
abstractNote = {A seismic detector for boreholes is described that has an accelerometer sensor block for sensing vibrations in geologic formations of the earth. The density of the seismic detector is approximately matched to the density of the formations in which the detector is utilized. A simple compass is used to orient the seismic detector. A large surface area shoe having a radius approximately equal to the radius of the borehole in which the seismic detector is located may be pushed against the side of the borehole by actuating cylinders contained in the seismic detector. Hydraulic drive of the cylinders is provided external to the detector. By using the large surface area wall-locking shoe, force holding the seismic detector in place is distributed over a larger area of the borehole wall thereby eliminating concentrated stresses. Borehole wall-locking forces up to ten times the weight of the seismic detector can be applied thereby ensuring maximum detection frequency response up to 2,000 hertz using accelerometer sensors in a triaxial array within the seismic detector.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1994},
month = {1}
}