(19)

(11)

EP 1 381 752 A1

(12)

(43) Date of publication: 21.01.2004 Bulletin 2004/04 (21) Application number: 01980489.7 (22) Date of filing: 10.10.2001

(51) International Patent Classification (IPC)7: E21B 36/02, E21B 43/24 (86) International application number: PCT/EP2001/011730 (87) International publication number: WO 2002/086283 (31.10.2002 Gazette 2002/44)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR Designated Extension States: AL LT LV MK RO SI (30) Priority: 24.04.2001 WO PCT/EP01/04641 (71) Applicant: SHELL INTERNATIONALE RESEARCHMAATSCHAPPIJ B.V. 2596 HR Den Haag (NL)	(72) Inventors: COLES, John, Matthew Katy, TX 77450 (US) KARANIKAS, John, Michael Houston, TX 77027 (US) MENOTTI, James, Louis Dickinson, TX 77539 (US) DE ROUFFIGNAC, Eric Houston, TX 77005 (US) VINEGAR, Harold, J. Houston, TX 77096 (US) WELLINGTON, Scott, Lee Bellaire, TX 77401 (US)