Geodetic Expressions of Plate Boundary Zone Dynamics from EarthScope Facilities

该奖项是根据2009年《美国复苏和再投资法》(公法111-5)资助的。我们正在使用来自EarthScope设施的新的连续GPS和地震数据产品，以调查地壳垂直运动和岩石圈结构之间可能的动态联系。我们正在将PBO和PBO核数据与来自全球分布的大型台站网络的GPS数据结合在一起，并使用最新的大地测量模型(包括IGS绝对相位中心)分析合并后的数据集。我们的目标是创建整个EarthScope焦点区域垂直速度场的高精度区域尺度图像。为了表征和提高GPS垂直速率估计的精度，我们正在开发新的时间序列分析方法。为了解释垂直速度场，我们正在发展基于弹性板弯曲的新的反分析方法。我们正在研究的模型参数包括垂直载荷和加载率，以及大陆岩石圈的强度(可能与时间有关)。地球望远镜地震部署提供了构成变形的板块边界带的大陆岩石圈结构的图像，增加了对地震速度、密度、衰减和各向异性结构的限制。大地测量和地震学数据集的组合应该对瞬时地幔流动、持续的震后应力松弛和其他过程的模型有影响。试点研究地区包括南加州和犹他州中部，以及目前数据集最强的类似地区。最终，我们预计这项技术将应用于整个美国西部毗邻的地区。我们正在建立的垂直运动、岩石圈结构和动力学之间的联系只是需要精确限制地壳垂直运动的许多重要科学调查途径之一。我们预计，我们生成的垂直运动数据产品和分析工具将在我们为期两年的项目的同时和之后得到广泛的应用。我们的研究团队包括一名职业早期的女性研究科学家和一名女性博士生。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).We are using new continuous GPS and seismic data products from EarthScope facilities to investigate possible dynamic links between vertical crustal motions and lithospheric structure. We are combining PBO and PBO NUCLEUS data with GPS data from a large network of globally distributed stations and analyzing the combined data set using the latest geodetic models, including IGS absolute phase centers. Our goal is to create high-precision regional-scale images of the vertical velocity field throughout the EarthScope focus area. In order to characterize and improve the precision of the GPS vertical rate estimates, we are developing new time series analysis methods. To interpret the vertical velocity field, we are developing new inverse analysis methods based on the flexure of elastic plates. The model parameters that we are investigating include vertical loads and load rates and (possibly time dependent) strength of the continental lithosphere. EarthScope seismic deployments are providing images of the structure of the continental lithosphere composing the deformed plate boundary zone, adding constraints on seismic velocity, density, attenuation, and anisotropy structure. The combination of geodetic and seismologic data sets should have implications for models of instantaneous mantle flow, ongoing postseismic stress relaxation, and other processes. Pilot study regions include southern California and central Utah, and similar areas where data sets are currently the strongest. Ultimately we anticipate applying the technique across the entire western conterminous US region. The associations between vertical motions, lithosphere structure, and dynamics that we are establishing constitute only one of many important avenues of scientific investigation that require precise constraints on vertical crustal motions. We anticipate that the vertical motion data products and analysis tools that we generate will have wide application concurrent with and beyond our two-year project. Our research team includes an early career female research scientist and a female PhD student.