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Physical Sciences and Mathematics Commons™
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Full-Text Articles in Physical Sciences and Mathematics
Nanoscale Evidence For Temperature-Induced Transient Rheology And Postseismic Fault Healing, Alexis K. Ault, Jordan L. Jensen, Robert G. Mcdermott, F.-A. Shen, B. R. Van Devener
Nanoscale Evidence For Temperature-Induced Transient Rheology And Postseismic Fault Healing, Alexis K. Ault, Jordan L. Jensen, Robert G. Mcdermott, F.-A. Shen, B. R. Van Devener
Geosciences Faculty Publications
Friction-generated heat and the subsequent thermal evolution control fault material properties and thus strength during the earthquake cycle. We document evidence for transient, nanoscale fault rheology on a high-gloss, light-reflective hematite fault mirror (FM). The FM cuts specularite with minor quartz from the Pleistocene El Laco Fe-ore deposit, northern Chile. Scanning and transmission electron microscopy data reveal that the FM volume comprises a2+ suboxides. Sub–5-nm-thick silica films encase hematite grains and connect to amorphous interstitial silica. Observations imply that coseismic shear heating (temperature >1000 °C) generated transiently amorphous, intermixed but immiscible, and rheologically weak Fe-oxide and silica. Hematite regrowth in …
Strike-Slip Fault Terminations At Seismogenic Depths: The Structure And Kinematics Of The Glacier Lakes Fault, Sierra Nevada United States, J. D. Kirkpatrick, Z. K. Shipton, James P. Evans, S. Micklethwaite, S. J. Lim, Peter R. Mckillop
Strike-Slip Fault Terminations At Seismogenic Depths: The Structure And Kinematics Of The Glacier Lakes Fault, Sierra Nevada United States, J. D. Kirkpatrick, Z. K. Shipton, James P. Evans, S. Micklethwaite, S. J. Lim, Peter R. Mckillop
Geosciences Faculty Publications
[1] Structural complexity is common at the terminations of earthquake surface ruptures; similar deformation may therefore be expected at the end zones of earthquake ruptures at depth. The 8.2 km long Glacier Lakes fault (GLF) in the Sierra Nevada is a left-lateral strike-slip fault with a maximum observed displacement of 125 m. Within the fault, pseudotachylytes crosscut cataclasites, showing that displacement on the GLF was accommodated at least partly by seismic slip. The western termination of the GLF is defined by a gradual decrease in the displacement on the main fault, accompanied by a 1.4 km wide zone of secondary …