This paper presents an algorithm for the automaticdetection of borehole breakouts and breakoutparameters (orientation, width) from wellbore images,and experience gained from different case studies. Thecreation of borehole breakouts depends on the in-situEarth stresses, the wellbore geometry, the annularpressure and the strength of the formation rock.Therefore, breakout analysis provides a means toconstrain stress magnitudes and orientation as well asthe rock strength, which are necessary prerequisites topredict wellbore stability.The algorithm is suitable for implementation in realtimewellbore stability systems and allows to monitoronly the breakout existence or non-existence andorientation (fast algorithm) and also to calculate thebreakout width (complex algorithm) to re-calibrate thepressure window (in particular, the shear failuregradient) if necessary.We show examples of electrical and density imageswith different resolution on which the algorithm wasapplied. The algorithm’s capabilities as well asoperating constraints are highlighted. Test runs provethat the breakout existence or non-existence andorientation can be delivered even from low-resolutionlogging while drilling (LWD) images, whichsignificantly improves real-time wellbore monitoringcapabilities. Still challenging is the calculation of thebreakout width by mathematical functions. Signalprocessing routines such as filtering and intelligentaveraging algorithms help to assign higher certainties tothe automatically calculated width.
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