Seismic sources
Abstract
Apparatus is described for placement in a borehole in the earth, which enables the generation of closely controlled seismic waves from the borehole. Pure torsional shear waves are generated by an apparatus which includes a stator element fixed to the borehole walls and a rotor element which is electrically driven to rapidly oscillate on the stator element to cause reaction forces transmitted through the borehole walls to the surrounding earth. Longitudinal shear waves are generated by an armature that is driven to rapidly oscillate along the axis of the borehole, to cause reaction forces transmitted to the surrounding earth. Pressure waves are generated by electrically driving pistons that press against opposite ends of a hydraulic reservoir that fills the borehole. High power is generated by energizing the elements for more than about one minute. 9 figs.
- Inventors:
- Issue Date:
- Research Org.:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- OSTI Identifier:
- 7098834
- Patent Number(s):
- 6039887
- Assignee:
- LBNL; ERA-14-001601; EDB-88-186314
- Patent Classifications (CPCs):
-
A - HUMAN NECESSITIES A47 - FURNITURE A47J - KITCHEN EQUIPMENT
- DOE Contract Number:
- AC03-76SF00098
- Resource Type:
- Patent
- Resource Relation:
- Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION; 58 GEOSCIENCES; SEISMIC SOURCES; DESIGN; BOREHOLES; INVENTIONS; P WAVES; S WAVES; SEISMIC SURVEYS; SEISMIC WAVES; CAVITIES; GEOPHYSICAL SURVEYS; PARTIAL WAVES; SURVEYS; 440400* - Well Logging Instrumentation; 580203 - Geophysics- Geophysical Survey Methods- (1980-1989)
Citation Formats
Green, M A, Cook, N G.W., McEvilly, T V, Majer, E L, and Witherspoon, P A. Seismic sources. United States: N. p., 1987.
Web.
Green, M A, Cook, N G.W., McEvilly, T V, Majer, E L, & Witherspoon, P A. Seismic sources. United States.
Green, M A, Cook, N G.W., McEvilly, T V, Majer, E L, and Witherspoon, P A. Mon .
"Seismic sources". United States.
@article{osti_7098834,
title = {Seismic sources},
author = {Green, M A and Cook, N G.W. and McEvilly, T V and Majer, E L and Witherspoon, P A},
abstractNote = {Apparatus is described for placement in a borehole in the earth, which enables the generation of closely controlled seismic waves from the borehole. Pure torsional shear waves are generated by an apparatus which includes a stator element fixed to the borehole walls and a rotor element which is electrically driven to rapidly oscillate on the stator element to cause reaction forces transmitted through the borehole walls to the surrounding earth. Longitudinal shear waves are generated by an armature that is driven to rapidly oscillate along the axis of the borehole, to cause reaction forces transmitted to the surrounding earth. Pressure waves are generated by electrically driving pistons that press against opposite ends of a hydraulic reservoir that fills the borehole. High power is generated by energizing the elements for more than about one minute. 9 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 20 00:00:00 EDT 1987},
month = {Mon Apr 20 00:00:00 EDT 1987}
}