EP 1088152 A1 20010404 - METHOD OF DETERMINING AZIMUTH OF A BOREHOLE
Title (en)
METHOD OF DETERMINING AZIMUTH OF A BOREHOLE
Title (de)
VERFAHREN ZUR BOHRLOCHAZIMUTBESTIMMUNG
Title (fr)
PROCEDE DE DETERMINATION DE L'AZIMUT D'UN TROU DE FORAGE
Publication
Application
Priority
- EP 99927912 A 19990614
- EP 9903940 W 19990614
- EP 98304821 A 19980618
Abstract (en)
[origin: WO9966173A1] A method is provided of determining an azimuth angle of a borehole formed in an earth formation using a magnetometer tool arranged in a drill string extending in the borehole, the magnetometer tool having a selected orientation relative to the drill string. The method comprises a) selecting at least two locations along the borehole at which the borehole has selected different borehole inclinations, b) for each selected location, arranging the drill string in the borehole such that the magnetometer tool is positioned at the selected location and operating the magnetometer tool so as to measure a local magnetic field including the earth magnetic field and a drill string magnetisation field having a component in a substantially vertical plane through the longitudinal axis of the drill string at the selected location, c) determining from the measured magnetic field and from the selected borehole inclinations, said component of the drill string magnetisation field, d) correcting the measured magnetic field for said component of the drill string magnetisation field, and e) determining from the corrected magnetic field, the borehole azimuth.
IPC 1-7
IPC 8 full level
E21B 47/022 (2006.01)
CPC (source: EP)
E21B 47/022 (2013.01)
Citation (search report)
See references of WO 9966173A1
Designated contracting state (EPC)
DE DK ES FR GB NL
DOCDB simple family (publication)
WO 9966173 A1 19991223; AU 4509399 A 20000105; AU 748917 B2 20020613; BR 9911307 A 20010313; CA 2334920 A1 19991223; CA 2334920 C 20080429; CN 1305565 A 20010725; DE 69923179 D1 20050217; DE 69923179 T2 20060105; EP 1088152 A1 20010404; EP 1088152 B1 20050112; ES 2237113 T3 20050716; NO 20006450 D0 20001218; NO 20006450 L 20010216; NO 320686 B1 20060116
DOCDB simple family (application)
EP 9903940 W 19990614; AU 4509399 A 19990614; BR 9911307 A 19990614; CA 2334920 A 19990614; CN 99807513 A 19990614; DE 69923179 T 19990614; EP 99927912 A 19990614; ES 99927912 T 19990614; NO 20006450 A 20001218