Flow-to-Friction Transition in Simulated Calcite Gouge: Experiments and Microphysical Modeling

Autor: Berend A. Verberne, Jianye Chen, André Niemeijer
Přispěvatelé: Experimental rock deformation
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Materials science
010504 meteorology & atmospheric sciences
Nucleation
earthquake nucleation
Slip (materials science)
01 natural sciences
Structural Geology
Physics::Geophysics
Fractures and Faults
Geochemistry and Petrology
Fault gouge
Earth and Planetary Sciences (miscellaneous)
Earthquake rupture
Rheology and Friction of Fault Zones
Transient response
flow-to-friction transition
Research Articles
0105 earth and related environmental sciences
Deformation (mechanics)
microphysical model
Dynamics and Mechanics of Faulting
calcite friction
Mechanics
brittle‐to‐ductile transition
brittle-to-ductile transition
Tectonophysics
Geophysics
Shear (geology)
Space and Planetary Science
flow‐to‐friction transition
Shear band
Chemistry and Physics of Minerals and Rocks/Volcanology
Research Article
rock deformation mechanisms
Zdroj: Journal of Geophysical Research: Solid Earth, 125(11)
Journal of Geophysical Research. Solid Earth
JGR Solid Earth, 125(11)
ISSN: 2169-9313
Popis: A (micro)physical understanding of the transition from frictional sliding to plastic or viscous flow has long been a challenge for earthquake cycle modeling. We have conducted ring‐shear deformation experiments on layers of simulated calcite fault gouge under conditions close to the frictional‐to‐viscous transition previously established in this material. Constant velocity (v) and v‐stepping tests were performed, at 550°C, employing slip rates covering almost 6 orders of magnitude (0.001–300 μm/s). Steady‐state sliding transitioned from (strong) v‐strengthening, flow‐like behavior to v‐weakening, frictional behavior, at an apparent “critical” velocity (v cr) of ~0.1 μm/s. Velocity‐stepping tests using v
Key Points We present a transition from flow to friction with increasing slip rate for a simulated carbonate fault sheared at 550°CA microphysically based model reproduces the lab‐observed flow‐to‐friction transition, including the transient frictional/flow behaviorsFaults exhibit semi‐brittle flow by creep cavitation prior to earthquake rupture nucleation at the BDT zone
Databáze: OpenAIRE