Larger imageMelissa Nunley

On the 14th of November 2001, a massive earthquake with a magnitude of 7.8 shook the Kokoxilli portion of the Kunlun fault in Northern Tibet. In a portion of the Kunlun fault (about 70 km) two parallel surface ruptures were mapped with strike-slip and dip-slip motion; because of the faults’ close proximity to each other, it has been proposed that the two are part of a slip partitioning fault system. Slip partitioned faults are difficult to model because of their complex branch geometry and dynamics. Adding to the already difficult task of modeling our complex faults, field observations have proven that both faults ruptured concurrently. In our project we want to explore all possible influences for simultaneous rupture and decipher what could cause them, so we can attempt to gain a better understanding of other complex branch system. In using our 3-D finite dynamic model, our rupture was unable to propagate to the more favorable dipping fault. We concluded that there is some force acting upon the branched system to cause simultaneous rupture. One possible explanation for the concurrent rupture we have explored is using barriers to force rupture propagation. By placing the barrier towards the bottom of the strike-slip fault rupture is caused to begin on the dipping fault while still propagating on the strike-slip. We have also examined the effects of slip hardening toward the surface. It seems that this only diminishes the amount of slip and does not promote concurrent rupture.

View field notes from other SURE Interns:   Select an intern... Alex Wilk Alexandra Millar Christina Velasquez Hannah Waterhouse Joshua Soble Lauren Steinberg Nathan Williams Patrick Dooling Trevor Thomas Tyanna Schlom