title: Slip-rate measurements on the Karakorum Fault may imply secular variations in fault motion.
abstract: Beryllium-10 surface exposure dating of offset moraines on one branch of the Karakorum Fault west of the Gar basin yields a long-term (140- to 20-thousand-year) right-lateral slip rate of approximately 10.7 +/- 0.7 millimeters per year. This rate is 10 times larger than that inferred from recent InSAR analyses ( approximately 1 +/- 3 millimeters per year) that span approximately 8 years and sample all branches of the fault. The difference in slip-rate determinations suggests that large rate fluctuations may exist over centennial or millennial time scales. Such fluctuations would be consistent with mechanical coupling between the seismogenic, brittle-creep, and ductile shear sections of faults that reach deep into the crust.
authors.affiliation: Laboratoire de Tectonique, Mécanique de la Lithosphère, Unité Mixte de Recherche (UMR) 7578, CNRS, Institut de Physique du Globe de Paris, 75252 Paris Cedex 05, France.
authors.forename: M-L
authors.initials: ML
authors.lastname: Chevalier
authors.forename: F J
authors.initials: FJ
authors.lastname: Ryerson
authors.forename: P
authors.initials: P
authors.lastname: Tapponnier
authors.forename: R C
authors.initials: RC
authors.lastname: Finkel
authors.forename: J
authors.initials: J
authors.lastname: Van Der Woerd
authors.forename: Li
authors.initials: L
authors.lastname: Haibing
authors.forename: Liu
authors.initials: L
authors.lastname: Qing