(19)
(11) EP 0 211 935 A1

(12)

(43) Date of publication:
04.03.1987 Bulletin 1987/10

(21) Application number: 86901587.0

(22) Date of filing: 07.02.1986
(51) International Patent Classification (IPC): 
E21B 43/ 26( . )
 E21B 47/ 12( . )
(86) International application number:
PCT/US1986/000262
(87) International publication number:
WO 1986/004636 (14.08.1986 Gazette 1986/18)
(84) Designated Contracting States:
AT BE CH DE FR GB IT LI LU

(30) Priority: 11.02.1985 US 19850700352

(71) Applicant: COMDISCO RESOURCES, INC.
Mountain View, CA 94901 (US)

(72) Inventors:
  • TITCHENER, Paul, F.
    Menlo Park, CA 94025 (US)
  • WALSH, Michael, J. M.
    Kentwood, CA 94904 (US)

   


(54) METHOD AND APPARATUS FOR DATA TRANSMISSION IN A WELL BORE CONTAINING A CONDUCTIVE FLUID