Scholarly record
INTEGRATED LWD METHODS IDENTIFY BOREHOLE BREAKOUTS IN HOSTILE ENVIRONMENTS
Abstract
Borehole instability issues account for approximately 18% of the non-productive time during drilling. The data needed for the planning of optimized wellbore trajectories and mud weight windows can come from multiple sources, notably Logging-While-Drilling (LWD) and wireline measurements. In particular, in-situ tectonic stresses can be inferred from the identification and characterization of breakouts (some of the most common processes that infringe upon the stability of boreholes). Two techniques can help to distinguish the breakouts: (1) determining borehole ovalization and (2) identifying the breakouts on borehole geophysical images. Multi-arm caliper logs from wireline imaging tools provide a direct measure of the borehole size but are not always available. Borehole shape can, however, be inferred from LWD geophysical imaging logs, notably from acoustic and density logs, which are very sensitive to standoff. Synthetic caliper curves can be computed from the standoff curves and converted into an oriented caliper image, displayed as a borehole wireframe. Sections through this borehole wireframe provide ovalization information and eliminate the uncertainty of breakouts direction estimation from resistivity images, which may show sometimes artifacts related to the presence of bad hole conditions or to very high formations true resistivity / mud resistivity ratios. This paper presents the application of LWD imaging data for better characterization of a borehole cross-section and easier breakouts detection in hostile environments (borehole excavations and rugosity, resistivity image artifacts, presence of fractures and faults). The proposed method enables detecting breakouts in real time or in memory mode. Determining the magnitude and orientation of borehole breakouts enables the validation or adjustment of geomechanical models and the selection of optimal parameters for the drilling mud.
Publication Impact Profile
Publication details
References3
Zoback M.D., Reservoir Geomechanics, Cambridge University Press, New York, U.S.A., 2007.
Chen J., Haramboure C., Pate L., Martin J., Barnett C., Responses and Field Tests from an LWD Microimaging Tool Using Discrete Energy Pulsing, International Petroleum Technology Conference, Doha, Qatar, paper IPTC-18275-MS, 2015.
Rider M., The Geological Interpretation of Well Logs, 2nd ed., Rider-French Consulting Ltd., Sutherland, Scotland, 2002.
Citing literature
Number of times cited according to Crossref: 1
View or Download full articleAccess options
SWS access login
Login as SWS Scientific CommitteeLogin as SWS Scientific PartnerLogin as SWS AuthorAuthors and approved SWS contributors will read and export their own linked papers after identity matching by SWS profile, email and SGEM GlobalID.
For librarian assistance: [email protected]
Purchase Instant Access
- Article can be downloaded after successful payment.
- Article may be used according to SWS library access terms.
- Article cannot be redistributed.
