Collaborative Research: Self-Consistent Kinematics and Dynamics of the U.S.

研究人员建议使用最近的GPS/VLBI/SLR观测，第四纪断层滑动速率，大地水准面，地壳厚度变化和地形数据来量化北美西部的应变率张量场和垂直平均偏应力张量场。迄今为止的结果表明，重力势能（GPE）的差异控制着大的断层正常压缩观察沿着加州海岸以及在瓦萨奇范围内的扩展。盆地和山脉的变形部分是由重力势能差驱动的，但那里的延伸方向受到板块相互作用应力的强烈影响。该分析将扩展到调查阿拉斯加北部和南部的应力状态，以包括里维拉三重接合点。分析领域将包括GPE差异对大西洋中脊的影响。耦合分析将调查的自洽运动学使用的观测GPS，VLBI，SLR和第四纪断层滑动速率。建议的联合运动学和动力学建模是重要的，因为它提供了一个全面的了解大地测量观测（GPS，VLBI，SLR），岩石圈应变率和岩石圈应力之间的关系。将使用正演模拟方法研究动力学的精细模型，并根据运动学模型确定速度边界条件。他们还将研究基础牵引力在影响动力学方面的可能作用。这项工作应提供重要的投入，以加强拟议的板块边界观测站和USAray倡议的规划和实施。

EAR-0001160Holt, William E.The investigators propose to use recent GPS/VLBI/SLR observations, Quaternary fault slip rates, the geoid, crustal thickness variations, and topography data to quantify both the strain rate tensor field and the vertically averaged deviatoric stress tensor field within western North America. Results to date indicate that gravitational potential energy (GPE) differences control the large fault-normal compression observed along the California coast as well as the extension at the Wasatch Range. Deformation in the Basin and Range is driven, in part, by gravitational potential energy differences but the extension directions there are strongly modified by plate interaction stresses. The analysis will be extended to investigate the state of stress north to Alaska, and south to include the Rivera Triple Junction. The area of analysis will include the effects of GPE differences out to the Mid-Atlantic Ridge. A coupled analysis will investigate the self-consistent kinematics using observations from GPS, VLBI, SLR, and Quaternary fault slip rates. The proposed joint kinematic and dynamic modeling is important because it provides a comprehensive understanding of the relationship between geodetic observations (GPS, VLBI, SLR), lithospheric strain rates, and lithospheric stress. Refined models of the dynamics will be investigated using forward modeling methods with velocity boundary conditions determined from the kinematic modeling. They will also investigate the possible role of basal tractions in affecting the dynamics. This work should provide important input to enhance the planning and implementation of the proposed Plate Boundary Observatory and USArray initiatives.