The Effect of Fluid Flow in Relay Ramps on Seismic Images
C. Botter, N. Cardozo, I. Lecomte, A. Rotevatn and G. Paton
Event name: Fourth International Conference on Fault and Top Seals
Session: Geophysical Approaches
Publication date: 20 September 2015
Info: Extended abstract, PDF ( 858.15Kb )
Price: € 20
Using an integrated workflow from an outcrop model in the Arches National Park, Utah, fluid flow simulation to seismic modelling, we intend to study the impact of a relay ramp system and its fluid composition on seismic images. Faulting in porous sandstone is associated to deformation bands that decrease the porosity and permeability locally. Based on those modified petrophysical properties, we run a fluid flow simulation and a ray-based pre-stack depth migration (PSDM) simulation to evaluate the impact of parameters such as illumination or wave frequency. We study the relay ramp at two stages of the fluid flow simulation: at the beginning and at the end. Only the changes in porosity around the faults are visible at the beginning, while fluid contacts affect also the model at the end. Resultant seismic images are able to show reflection and diffraction for the two faults when constant fluid saturation at the beginning. However, the thin layer of water at the top of model has a much stronger impact at the end and the faults can hardly be interpreted. Our methodology provides ways to better understand how faulting impact seismic, and therefore to tune acquisition and processing parameters for fault characterization.