This paper presents an algorithm for the automatic detection of borehole breakouts and breakout parameters (orientation, width) from wellbore images, and experience gained from different case studies. The creation of borehole breakouts depends on the in-situ Earth stresses, the wellbore geometry, the annular pressure and the strength of the formation rock. Therefore, breakout analysis provides a means to constrain stress magnitudes and orientation as well as the rock strength, which are necessary prerequisites to predict wellbore stability. The algorithm is suitable for implementation in real- time wellbore stability systems and allows to monitor only the breakout existence or non-existence and orientation (fast algorithm) and also to calculate the breakout width (complex algorithm) to re-calibrate the pressure window (in particular, the shear failure gradient) if necessary. We show examples of electrical and density images with different resolution on which the algorithm was applied. The algorithm’s capabilities as well as operating constraints are highlighted. Test runs prove that the breakout existence or non-existence and orientation can be delivered even from low-resolution logging while drilling (LWD) images, which significantly improves real-time wellbore monitoring capabilities. Still challenging is the calculation of the breakout width by mathematical functions. Signal processing routines such as filtering and intelligent averaging algorithms help to assign higher certainties to the automatically calculated width.
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