Peer-reviewed articles 17,970 +



Title: INTEGRATED LWD METHODS IDENTIFY BOREHOLE BREAKOUTS IN HOSTILE ENVIRONMENTS

INTEGRATED LWD METHODS IDENTIFY BOREHOLE BREAKOUTS IN HOSTILE ENVIRONMENTS
C.L. CIUPERCA;B. M. NICULESCU;P. Kravets
1314-2704
English
19
1.2
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.
conference
19th International Multidisciplinary Scientific GeoConference SGEM 2019
19th International Multidisciplinary Scientific GeoConference SGEM 2019, 30 June - 6 July, 2019
Proceedings Paper
STEF92 Technology
International Multidisciplinary Scientific GeoConference-SGEM
Bulgarian Acad Sci; Acad Sci Czech Republ; Latvian Acad Sci; Polish Acad Sci; Russian Acad Sci; Serbian Acad Sci & Arts; Slovak Acad Sci; Natl Acad Sci Ukraine; Natl Acad Sci Armenia; Sci Council Japan; World Acad Sci; European Acad Sci, Arts & Letters; Ac
929-936
30 June - 6 July, 2019
website
cdrom
5163
borehole imaging;breakouts;geophysical well logs;hostile environments;Logging-While-Drilling