4D attenuation analysis for permeability estimates in hydraulically induced fractures

David Cho, Bill Goodway, Marco A. Perez, Andrew Iverson, Gary F. Margrave

The effect of wave induced fluid motion between fractures and pores results in complex elastic stiffness coefficients that ultimately gives rise to frequency-dependent attenuation. Therefore, permeability estimates are obtainable through a spectral analysis of the seismic wavefield. In this study, we analyze the attenuation response associated with a time-lapse seismic survey acquired before and after hydraulic fracturing to investigate the permeability within the stimulated zone. The results obtained from the attenuation analysis were in qualitative agreement with microseismic observations and 4D seismic amplitude and traveltime anomalies, suggesting that a permeable fault diverted the energy from the hydraulic fracture treatment to re-stimulate a specific portion of the reservoir.