Analysis And Characterization Of EI-Reno Subsurface Strike-slip Fault Zone Using 3D Seismic Attributes In The Anadarko Basin

Fault damage-zones may significantly affect subsurface fluid migration and the development of unconventional resources.Most analyses of fault damage-zones are based on direct field observations,and we expand these analyses to the subsurface by investigating the damage-zone structure of a 32-km long right-lateral strike-slip fault in Oklahoma based on seismic attributes including volumetric coherence,variance,dip azimuth,and curvature.We used the 3D seismic attribute of coherence to first define its regional and background levels,and then evaluated the damage-zone dimensions at multiple sites.We found damage-zone thickness of ?1615m at a segment that is dominated by subsidiary faults,and is slightly thicker at a segment with a pull-apart basin.The damage-zone intensity decays exponentially with distance from the fault core,in agreement with field observations and distribution of seismic events.The coherence map displays a strong asymmetry of the damage-zone between the two sides of the fault and is related to the subsidiary structures of the fault-zone.We discuss the effects of heterogeneous stress field on damage-zone evolution through the detected subsidiary structures.