  Reservoir simulations for subsurface processes play an important role in
successful deployment of geoscience applications such as geothermal energy
extraction and geo-storage of fluids. These simulators provide time-laps
dynamics of the coupled poro-mechanical processes within the reservoir and its
over-, under-, and side-burden environments. For more reliable operations, it
is crucial to connect these reservoir simulation results with the seismic
surveys (i.e., observation data). However, despite being crucial, such
integration is challenging due to the fact that the reservoir dynamics alters
the seismic parameters. In this work, a coupled reservoir simulation and
time-lapse seismic methodology is developed for multiphase flow operations in
subsurface reservoirs. To this end, a poromechanical simulator is designed for
multiphase flow and connected to a forward seismic modeller. This simulator is
then used to assess a novel methodology of seismic monitoring by isolating the
reservoir signal from the entire reflection response. This methodology is shown
to be able to track the development of the fluid front over time, even in the
presence of a highly reflective overburden with strong time-lapse variations.
These results suggest that the proposed methodology can contribute to a better
understanding of fluid flow in the subsurface. Ultimately, this will lead to
improved monitoring of reservoirs for underground energy storage or production.
