Abstract
We report the emergence of anomalous (non-Fickian) transport through a rough-walled fracture as a result of increasing normal stress on the fracture. We show that the origin of this anomalous transport behavior can be traced to the emergence of a heterogeneous flow field dominated by preferential channels and stagnation zones, as a result of the larger number of contacts in a highly stressed fracture. We show that the velocity distribution determines the late-time scaling of particle spreading, and velocity correlation determines the magnitude of spreading and the transition time from the initial ballistic regime to the asymptotic anomalous behavior. We also propose a spatial Markov model that reproduces the transport behavior at the scale of the entire fracture with only three physical parameters. Our results point to a heretofore unrecognized link between geomechanics and particle transport in fractured media.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 46-54 |
| Number of pages | 9 |
| Journal | Earth and Planetary Science Letters |
| Volume | 454 |
| DOIs | |
| State | Published - Nov 15 2016 |
| Externally published | Yes |
Bibliographical note
Funding Information:This work was funded by the U.S. Department of Energy through a DOE CAREER Award (grant DE-SC0003907 ) and a DOE Mathematical Multifaceted Integrated Capability Center (grant DE-SC0009286 ). P.K.K. gratefully acknowledges support from the Korean Ministry of Land, Infrastructure and Transport ( 16AWMP-B066761-04 ). Data used in this manuscript can be obtained from the corresponding author ( juanes@mit.edu ).
Publisher Copyright:
© 2016
Keywords
- anomalous transport
- fracture
- groundwater flow
- roughness
- spatial Markov model