Publication Details |
| Category | Text Publication |
| Reference Category | Journals |
| DOI | 10.1016/j.gete.2024.100600 |
| Title (Primary) | Shear-induced fluid localization, episodic fluid release and porosity wave in deformable low-permeability rock salt |
| Author | Wang, Y.; Shao, H.; Kuhlman, K.L.; Jove-Colon, C.F.; Kolditz, O.
|
| Source Titel | Geomechanics for Energy and the Environment |
| Year | 2024 |
| Department | ENVINF |
| Volume | 40 |
| Page From | art. 100600 |
| Language | englisch |
| Topic | T8 Georesources T5 Future Landscapes |
| Keywords | Nuclear waste disposal; Rock salt; Low-permeability medium; Brine migration; Hydromechanical coupling; Nonlinear dynamics |
| Abstract | Understanding
fluid distribution and migration in deformable low-permeability rock
salt is critical for geologic disposal of nuclear waste. Field
observations indicate that fluids in a salt formation are likely
compartmentalized into relatively isolated patches and fluid release
from such a formation is generally episodic. The underlying mechanism
for these phenomena remains poorly understood. In this paper, a
hydrological-mechanical model is formulated for fluid percolation in a
rock salt formation under a deviatoric stress. Using a linear stability
analysis, we show that a porosity wave (a train of alternating high and
low porosity pockets) can emerge from positive feedbacks among
intergranular wetting, grain boundary weakening and shear-induced
material dilatancy. Fluid localization or episodic release can be viewed
as a stationary or propagating porosity wave respectively. Fluid
pockets transported via a porosity wave remain relatively isolated with
minimal mixing between neighboring pockets. We further show that the
velocity of fluid flow can be significantly enhanced by the emergence of
a porosity wave. The concept and the related model presented in this
paper provide a unified consistent explanation for the key features
observed in fluid flow in rock salt. The similar process is expected to
occur in other deformable low-permeability media such as shale and
partially molten rocks under a deviatoric stress. Thus, the result
presented here has an important implication to hydrocarbon expulsion
from shale source rocks, radioactive waste isolation in a tight rock
repository, and caprock integrity of a subsurface gas (CO2, H2 or CH4)
storage system. It may also help develop a new engineering approach to
fluid injection into or extraction from unconventional reservoirs. |
| Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=30133 |
| Wang, Y., Shao, H., Kuhlman, K.L., Jove-Colon, C.F., Kolditz, O. (2024): Shear-induced fluid localization, episodic fluid release and porosity wave in deformable low-permeability rock salt Geomech. Energy Environ. 40 , art. 100600 10.1016/j.gete.2024.100600 |
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