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USGS · 70012658

Well bore breakouts and in situ stress

Mark D. Zoback·Daniel Moos·Larry Mastin·Roger N. Anderson
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Abstract

The detailed cross-sectional shape of stress induced well bore breakouts has been studied using specially processed ultrasonic borehole televiewer data. Breakout shapes are shown for a variety of rock types and introduce a simple elastic failure model which explains many features of the observations. Both the observations and calculations indicate that the breakouts define relatively broad and flat curvilinear surfaces which enlarge the borehole in the direction of minimum horizontal compression. Refs.

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Mark D. Zoback, Daniel Moos, Larry Mastin, Roger N. Anderson. 2012-09-20. Well bore breakouts and in situ stress. https://doi.org/10.1029/jb090ib07p05523

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