A coupled phase-field and reactive-transport framework for fracture
propagation in poroelastic media
Abstract
We present a novel approach to model hydro-chemo-mechanical responses in
rock formations subject to fracture propagation within chemically active
rock formations. The developed framework integrates the mechanisms of
reactive transport, fluid flow and transport in porous media, and
fracture propagation in poroelastic media using the phase-field model.
The solution approach integrates the geochemical package PHREEQC with a
finite-element open-source platform, FEniCs. Thereby, the PHREEQC solver
is used to calculate the localized chemical reaction, including solid
dissolution/precipitation. The resulting solid weakening by chemical
damage is estimated from the reaction-induced porosity change. The
proposed coupled model was verified with previous numerical results and
applied to a synthetic case exhibiting hydraulic fracturing enhanced
with chemical damage. Simulation results suggest that mechanical failure
could be accelerated in the presence of ongoing chemical processes due
to rock weakening and porosity changes, allowing the nucleation, growth,
and development of fractures.