GNGTS 2018 - 37° Convegno Nazionale

524 GNGTS 2018 S essione 2.3 of the ICHESE (International Commission on Hydrocarbon Exploration and Seismicity in the Emilia region; ICHESE, 2014) concluded that it is highly unlikely that the activity in the Cavone oil field was able to produce stress variations to “induce” the 2012 Emilia sequence; furthermore, they concluded that with the available data it is not possible to test nor to exclude a contribution of the hydrocarbon exploitation for “triggering” the activity. In another study, which includes geomechanical field studies performed after the ICHESE report, Astiz et al. (2014) concluded that except within a few hundred meters of the injector well, the fluid pressure within the reservoir is dominated by the net depletion of the field due to oil production, and that the 2012 Emilia sequence was purely correlated to tectonic stress release, rather than triggered by industrial activities performed at the Cavone oil field. Our interest in this case study is to deeply analyse the microseismicity in the surroundings of this field; to perform this task, we have availability of a catalog of about 1000 events recorded in this zone between 2010 and 2017 (thus including the 2012 Emilia seismic sequence) by the Cavone oil field network (Fig. 1). The ultimate goal of our analysis is the implementation of methods for time-dependent probabilistic hazard assessment. An adequate method for non-stationary probabilistic seismic hazard analysis, associated with performance-based criteria to assess potential impacts of induced seismicity (if any), may constitute the base for the implementation of objective mitigation actions. In this framework, of ultimate objective is to propose possible alternatives to the “classical traffic light” methods (for example Bommer et al, 2006) which are based on fixed thresholds of magnitude exceeded during industrial operations. Acknowledgements. 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