The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 29, 1992
Filed:
Jun. 28, 1991
Applicant:
Inventors:
Assignee:
Chinetsu Gijutsu Kaihatsu Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01V / ; G01V / ; E21B / ;
U.S. Cl.
CPC ...
324346 ; 73155 ; 166254 ; 324325 ; 324339 ;
Abstract
A three-dimensional detection system for detecting fractures and their distributions in the earth crust utilizing an artificial magnetic field which comprises: a magnetic particle tracer being injected into the fractures of the earth crust, having high magnetic permeability and specific weight of the same degree with a fluid substance existing in the fractures; and inner borehole magnetic field detecting devices being hung in boreholes which are dug in the earth crust and having transmitters and/or receivers operating at a predetermined frequency.