Fault Architecture and Roughness

Summary Among fault plane geometric attributes, asperities and roughness play an important role on the fault frictional behaviour and further growth. Fault imaging in seismic data has evolved significantly over the past decades, progressing from manual picking of fault traces to the use of seismic attributes, and more recently, to the application of deep learning-based methods. New advances in imaging faults in 3D reflection seismic data has enabled capturing fault plane 3D shape with internal segments. We investigated the structural characteristics of several normal faults in siliciclastic dominated lithology imaged in seismic surveys from the Norwegian Continental Shelf (Barents Sea). Our study followed a four-step workflow: fault imaging and 3D geometry extraction; asperity identification and characterization; throw measurement; and fault roughness analysis. This integrated approach enabled a detailed investigation of the relationship between fault asperities and localized variations in throw and strike along the fault planes. Our results show that fault roughness increases adjacent to asperities, where the throw usually increases and there are sudden changes in the fault segments’ strike.