Carbonation of Serpentinite in Creeping Faults of California

Several large strike slip faults in central and northern California accommodate plate motions through aseismic creep. Although there is no consensus regarding the underlying cause of creep, aqueous fluids mechanically weak, velocity-strengthening minerals appear to play a role. This study integrates field observations thermodynamic modeling examine possible relationships between occurrence serpentinite, silica-carbonate rock, CO2-rich creeping California. Our models predict that carbonation serpentinite leads formation talc magnesite, followed by rock. While abundant exposures rock indicate complete carbonation, serpentinite-hosted spring are strongly supersaturated with at elevated temperatures. Hence, likely ongoing parts San Andres Fault system operates conjunction other modes may further enhance potential for thereby limiting earthquakes.