Microphysical Modeling of Carbonate Fault Friction at Slip Rates Spanning the Full Seismic Cycle

Autor: André Niemeijer, Jianye Chen, Christopher J. Spiers
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Rheology of the Lithosphere and Mantle
Informatics
010504 meteorology & atmospheric sciences
Earthquake Source Observations
Nucleation
high‐velocity friction
010502 geochemistry & geophysics
01 natural sciences
Structural Geology
Fault friction
Rheology: General
Ionospheric Physics
Earth and Planetary Sciences (miscellaneous)
Seismology
Earthquake Interaction
Forecasting
and Prediction

superplastic flow
Exploration Geophysics
Gravity Methods
Ocean Predictability and Prediction
Mechanics
Grain size
Seismic Cycle Related Deformations
Tectonic Deformation
Oceanography: General
Policy
Geophysics
Time Variable Gravity
Estimation and Forecasting
Seismicity and Tectonics
Space Weather
Shear band
Mathematical Geophysics
frictional heating
Geology
Probabilistic Forecasting
Research Article
Lithosphere
Satellite Geodesy: Results
Slip (materials science)
Plasticity
high-velocity friction
Radio Science
Physics::Geophysics
Earthquake Dynamics
Geochemistry and Petrology
Magnetospheric Physics
Rheology and Friction of Fault Zones
Geodesy and Gravity
Ionosphere
Monitoring
Forecasting
Prediction

0105 earth and related environmental sciences
Grain Boundary Sliding
Gravity anomalies and Earth structure
Continental Crust
seismic cycle
Dynamics and Mechanics of Faulting
earthquake/rupture modeling
Policy Sciences
dynamic fault weakening
Interferometry
Tectonophysics
Deformation mechanism
Space and Planetary Science
Subduction Zones
Hydrology
Transient Deformation
Prediction
Natural Hazards
Chemistry and Physics of Minerals and Rocks/Volcanology
Forecasting
Zdroj: Journal of Geophysical Research: Solid Earth, 126(3), 1
Journal of Geophysical Research. Solid Earth
ISSN: 2169-9313
Popis: Laboratory studies suggest that seismogenic rupture on faults in carbonate terrains can be explained by a transition from high friction, at low sliding velocities (V), to low friction due to rapid dynamic weakening as seismic slip velocities are approached. However, consensus on the controlling physical processes is lacking. We previously proposed a microphysically based model (the “Chen–Niemeijer–Spiers” [CNS] model) that accounts for the (rate‐and‐state) frictional behavior of carbonate fault gouges seen at low velocities characteristic of rupture nucleation. In the present study, we extend the CNS model to high velocities (1 mm/s ≤ V ≤ 10 m/s) by introducing multiple grain‐scale deformation mechanisms activated by frictional heating. As velocity and hence temperature increase, the model predicts a continuous transition in dominant deformation mechanisms, from frictional granular flow with partial accommodation by plasticity at low velocities and temperatures, to grain boundary sliding with increasing accommodation by solid‐state diffusion at high velocities and temperatures. Assuming that slip occurs in a localized shear band, within which grain size decreases with increasing velocity, the model results capture the main mechanical trends seen in high‐velocity friction experiments on room‐dry calcite‐rich rocks, including steady‐state and transient aspects, with reasonable quantitative agreement and without the need to invoke thermal decomposition or fluid pressurization effects. The extended CNS model covers the full spectrum of slip velocities from earthquake nucleation to seismic slip rates. Since it is based on realistic fault structure, measurable microstructural state variables, and established deformation mechanisms, it may offer an improved basis for extrapolating lab‐derived friction data to natural fault conditions.
Key Points We extend a microphysical friction model from earthquake nucleation to seismic slip velocitiesThe extended model predicts steady‐state and transient frictionModel results reproduce high‐velocity friction experiments on simulated calcite fault gouges
Databáze: OpenAIRE