Short- and long-term earthquake triggering along the strike-slip Kunlun fault, China: Insights gained from the Ms 8.1 Kunlun earthquake and other modern large earthquakes

Following the 2001 M(s)8.1 Kunlun earthquake, earthquake records of more than 10 years, in addition to more than one century's records of large earthquakes, provide us with a chance to examine short-term (days to a few years) and long-term (years to decades) seismic triggering following a magnitude similar to 8 continental earthquake along a very long strike-slip fault, the Kunlun fault system, located in northern Tibet, China. Based on the calculations of coseismic Coulomb stress changes (Delta CFS) from the larger earthquake and post-seismic stress changes due to viscoelastic stress relaxation in the lower crust and upper mantle, we examined the temporal evolution of seismic triggering. The ETAS (epidemic type aftershocks sequence) model shows that the seismic rate in the aftershock area over similar to 10 years was higher than the background seismicity before the mainshocic. Moreover, we discuss long-term (years to decades) triggering and the evolution of stress changes for the sequence of five large earthquakes of M >= 7.0 that ruptured the Kunlun fault system since 1937. All subsequent events of M 7.0 occurred in the regions of positive accumulated Delta CFS. These results show that short-term (up to 200 days in our case) triggering along the strike-slip Kunlun fault is governed by coseismic stress changes, while long-term triggering is somewhat due to post-seismic Coulomb stress changes resulting from viscoelastic relaxation. (c) 2014 Elsevier B.V. All rights reserved.