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Title: Tuned borehole gravity gradiometer

Abstract

A tuned borehole gravity gradiometer is described for detecting variations in gravity gradient which consists of: a suspended dipole mass system having symmetrically distributed dipole masses and suspension means for suspending the dipole masses such that the gravity gradient to be measured produces an angular displacement about a rotation axis of the dipole mass system from a reference position; and tuning means with the dipole mass system for selectively varying the sensitivity to angular displacements with respect to the rotation axis of the dipole mass system to variations in gravity gradient, wherein the tuning means includes means for selectively varying the metacentric height of the dipole mass system.

Inventors:
;
Publication Date:
OSTI Identifier:
5563613
Patent Number(s):
US 4581932
Assignee:
Standard Oil Co., Chicago, IL NOV; EDB-86-114405
Resource Type:
Patent
Resource Relation:
Patent File Date: Filed date 20 Dec 1984
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; 47 OTHER INSTRUMENTATION; GRAVITY LOGGING; WELL LOGGING EQUIPMENT; PETROLEUM DEPOSITS; BOREHOLES; DIPOLES; GRAVITY SURVEYS; INCIDENCE ANGLE; ROTATION; SENSITIVITY; TUNING; CAVITIES; EQUIPMENT; GEOLOGIC DEPOSITS; GEOPHYSICAL SURVEYS; MINERAL RESOURCES; MOTION; MULTIPOLES; RESOURCES; SURVEYS; WELL LOGGING; 020200* - Petroleum- Reserves, Geology, & Exploration; 440400 - Well Logging Instrumentation

Citation Formats

Lautzenhiser, T.V., and Nekut, A.G. Jr. Tuned borehole gravity gradiometer. United States: N. p., 1986. Web.
Lautzenhiser, T.V., & Nekut, A.G. Jr. Tuned borehole gravity gradiometer. United States.
Lautzenhiser, T.V., and Nekut, A.G. Jr. Tue . "Tuned borehole gravity gradiometer". United States. doi:.
@article{osti_5563613,
title = {Tuned borehole gravity gradiometer},
author = {Lautzenhiser, T.V. and Nekut, A.G. Jr.},
abstractNote = {A tuned borehole gravity gradiometer is described for detecting variations in gravity gradient which consists of: a suspended dipole mass system having symmetrically distributed dipole masses and suspension means for suspending the dipole masses such that the gravity gradient to be measured produces an angular displacement about a rotation axis of the dipole mass system from a reference position; and tuning means with the dipole mass system for selectively varying the sensitivity to angular displacements with respect to the rotation axis of the dipole mass system to variations in gravity gradient, wherein the tuning means includes means for selectively varying the metacentric height of the dipole mass system.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Apr 15 00:00:00 EST 1986},
month = {Tue Apr 15 00:00:00 EST 1986}
}
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