Natural and Experimental Evidence of Melt Lubrication of Faults During Earthquakes

Melt produced by friction during earthquakes may act either as a coseismic fault lubricant or as a viscous brake. Here we estimate the dynamic shear resistance ([tau][subscript f]) in the presence of friction-induced melts from both exhumed faults and high-velocity (1.28 meters per second) frictiona...

Full description

Saved in:
Bibliographic Details
Published in:Science (American Association for the Advancement of Science) 2006-02, Vol.311 (5761), p.647-649
Main Authors: Di Toro, Giulio, Hirose, Takehiro, Nielsen, Stefan, Pennacchioni, Giorgio, Shimamoto, Toshihiko
Format: Article
Language:English
Subjects:
Aluminum
Earth sciences
Earth, ocean, space
Earthquakes
Earthquakes, seismology
Exact sciences and technology
Experimental data
Fault zones
Friction
Internal geophysics
Lubrication
Marine
Melting
Outcrops
Seismology
Shear stress
Sliding
Specimens
Tectonics. Structural geology. Plate tectonics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Melt produced by friction during earthquakes may act either as a coseismic fault lubricant or as a viscous brake. Here we estimate the dynamic shear resistance ([tau][subscript f]) in the presence of friction-induced melts from both exhumed faults and high-velocity (1.28 meters per second) frictional experiments. Exhumed faults within granitoids (tonalites) indicate low [tau][subscript f] at 10 kilometers in depth. Friction experiments on tonalite samples show that [tau][subscript f] depends weakly on normal stress. Extrapolation of experimental data yields [tau][subscript f] values consistent with the field estimates and well below the Byerlee strength. We conclude that friction-induced melts can lubricate faults at intermediate crustal depths.
ISSN:0036-8075
1095-9203
DOI:10.1126/science.1121012