(19)

(11)

EP 1 687 505 A1

(12)

(43) Date of publication: 09.08.2006 Bulletin 2006/32 (21) Application number: 04817283.7 (22) Date of filing: 27.10.2004

(51) International Patent Classification (IPC):  E21B 7/18(2006.01) E21B 10/60(2006.01) (86) International application number: PCT/EP2004/052677 (87) International publication number: WO 2005/040546 (06.05.2005 Gazette 2005/18)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR (30) Priority: 29.10.2003 EP 03104007 08.07.2004 WO PCT/EP2004/051407 (71) Applicant: SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V. 2596 HR The Hague (NL)	(72) Inventor: BLANGE' , Jan-Jette NL-2288 GS Rijswijk (NL)