Microseismic event location provides a plethora of information about underground processes such as hydraulic fracturing, steam injection or mining and volcano activities. Nevertheless, accuracy is limited by acquisition geometry and errors in the velocity model and time picks. Although microseismic events can happen anywhere, they tend to re-occur in the same zone. This thesis describes a post-processing technique to relocate events originated in the same source region based on the double-difference method. This technique includes a crosscorrelation procedure to detect similar events and correct time picking errors. The performance of the algorithm is tested on synthetic data and a set of microseismic events recorded in a mine. The method significantly improves locations of similar events, compared to a conventional grid-search algorithm, revealing seismicity patterns likely associated with routine mining operations. The method also includes plots used for quality control of time picking and event location, facilitating geological interpretations.
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