Constraints on fault mechanics and seismic hazard from the integration of high- resolution topography and InSAR datasets

Chelsea P. Scott博士被授予美国国家科学基金会EAR博士后奖学金，在亚利桑那州立大学开展研究和教育活动。这项研究的目的是改善对地质和大地测量数据集估计的断层滑动率的限制。准确的滑动率对于正确估计一个地区未来的地震活动至关重要。斯科特博士将使用一种结合高分辨率地形和卫星雷达数据集的新方法，将近场和远场地面变形的互补约束结合在一起。这项研究提高了对断层力学的认识，将有助于更好地确定地质记录中的断层滑动率，并对古地震滑动率的不确定性进行量化。此外，PI将在nsf赞助的开放地形设施中领导研讨会，在亚利桑那州立大学共同开发本科课程，并与高中女生一起提高计算机编码技能。本研究将着重利用地表应变的大小和分布的近场和远场约束来推断断层滑动的深度变异性。用InSAR数据制作的断层滑动模型通常表明地壳上部几公里的断层滑动很小，这与地形数据不一致。该项目的第一个目标是检查由InSAR和差分地形数据联合反演推断的断层滑动分布。该项目的第二个目标是研究在许多地震周期中应变积累的含义。该研究将改善对发震地壳同震断层滑动相对比例的限制。对断层力学的进一步理解将为该项目的进一步工作提供输入，该项目将侧重于量化沿走向同震断层滑动的长期变化以及在许多模拟地震周期中地表和深度滑动之间的比率。

Dr. Chelsea P. Scott has been granted an NSF EAR Postdoctoral fellowship to carry out research and education activities at Arizona State University. The investigation will aim at improving constraints on fault slip rates estimated from both geologic and geodetic datasets. Accurate slip rates are critical to properly estimate future seismic activity in a region. Dr. Scott will use a novel approach of combining high-resolution topography and satellite radar datasets, bringing together complementary constraints on near- and far- field ground deformation. The improved understanding of fault mechanics from this study will result in better determination of fault slip rates in the geologic record and on quantified uncertainties of paleoseismic slip rates. In addition, the PI will lead workshops at the NSF-sponsored Open Topography facility, co-develop undergraduate courses at ASU, and promote computer-coding skills with high school women.This research will focus on using near- and far- field constraints on the magnitude and distribution of surface strain to infer the depth variability of fault slip. The fault slip models produced with InSAR data typically suggest little fault slip in the upper several kilometers of the crust, which is at odds with the topography data. The first goal of this project is to examine the distribution of fault slip inferred from the joint inversion of InSAR and differential topography data. The second goal of the project is to examine the implications for strain accumulation over many earthquake cycles. The study will improve constraints on the relative proportions of coseismic fault slip in the seismogenic crust. The improved understanding on fault mechanics will serve as input to further work in this project that will focus on quantifying the long-term variation in along-strike coseismic fault slip and the ratio between slip at the surface and at depth over many simulated earthquake cycles.