[S07-P] Poster

[S07-P-10] Segmentation of slow slip events in south central Alaska possibly controlled by a subducted oceanic plateau

^○Haotian Li^{1, 2}, Meng Wei², Shiyong Zhou¹, Duo Li³, Yajing Liu³, Younghee Kim⁴ (1.Peking University, Beijing, China, 2.University of Rhode Island, United States, 3.McGill University, Canada, 4.Seoul National University, South Korea)

GPS data in south central Alaska show possible segmentation of slow slip behavior along the subduction zone. We hypothesize that the subducted Yakutat plateau created such segmentation through modification of stress or friction property of the fault zone. To test this hypothesis, we simulate the SSEs in the framework of rate and state friction. We use non-planar fault model to incorporate the geometric effect on SSE behavior. We also systematically explore the parameter space to find the most likely scenario and rule out some possibilities. The goal is to identify how such segmentation can be related to the subducted plateau in a physics model. Simulations show different effective normal stress could create such segmentation even though other mechanism exists. This is consistent with an idea that subducted plateau caused elevated effective normal stress in the fault zone, producing larger SSEs above it. The buoyant plateau provides additional normal stress on the fault interface, which results in larger SSEs in the east segment. Our results indicate that geological features have a long-lived impact on slip behavior of subduction faults. We also explored the interactions between the two SSE patches, as shown in the 2008-2013 slip events. Simulations show that the closeness of these two patches creates additional complexity in the behavior of SSEs.