T. Khachkova
M. Novikov
V. Lisitsa
Y. Zhang M. Lebedev

: 81st EAGE Conference and Exhibition 2019 Embrace Change - Creativity for the Future (London, United Kingdom, 3-6 June 2019)

Chemical reaction caused by CO2 injection into host rock may significantly change its physical properties. In particular, CO2-enriched brine presence within the fracture-porous carbonate reservoirs results in weakening of fracture material and increases its permeability and porosity as wel as tortuosity. In our study, we estimate numerically the material parameters of a limestone using its CT-images. Next we apply obtained physical properties of the material in the numerical modeling of seismic wave propagation in fractured-porous media with different connectivity degree of the fractures. Results show, that the partial dissolution of the fracture-filling material leads to stronger overall seismic attenuation due to the wave-induced fluid flow and velocity drop. However, this attenuation mechanism impact within connected fractures remains local, and fracture-to-fracture fluid flow give no significant contribution to the overall attenuation.