Paleoseismology along Earthscope-PBO Dense Array of GPS Stations Across the Interior of the Great Basin

美国西部和太平洋-北美板块边界现在是美国国家科学基金会赞助的主要地球望远镜倡议的重点，该倡议的主要目的是(1)利用全球定位系统和地震仪器等现代观测技术来调查北美大陆的结构和演化，以及(2)有助于减轻地质灾害的风险。太平洋-北美板块运动并不局限于加利福尼亚州的圣安德烈亚斯断层系统。它还包括以盆地式和山脉式变形为特征的大盆地地貌省，并包括西至内华达州雷诺、东至得克萨斯州盐湖城之间、宽度达800公里的区域。大盆地是世界上扩散大陆伸展的典型例子之一。这项野外研究旨在量化大盆地内部主要活动断裂上晚更新世地震位移(古地震学)的发生。这些研究的地点位于预期的地球望远镜--部署地理位置系统仪器，将在整个大盆地形成密集的阵列。实地研究的动机源于这样一种理解，即北美板块边界的运动学和力学将需要测量整个边界在地质时间内的变形速度、样式和演化。因此，当地球望远镜-板块边界观测站地理位置系统仪器测量应变累积时，我们的研究正在测量应变是如何释放的。我们所获得的知识正在被用来理解地震过程的物理过程，整个美国西部的构造和地形的发展，以及当代应变信号本身。此外，这项研究正在支持一名博士生的教育，研究网站被用于大学实地课程，作为研究方法的介绍。还打算将这项了解地震过程物理过程的工作纳入确定地震危险和预测未来地震的地点和规模的工作中。

The western United States and the Pacific-North American plate boundary are now the focus of the major NSF-sponsored initiative Earthscope that is largely aimed at (1) employing modern observational technologies such as Global Positioning Systems and seismic instrumentation to investigate the structure and evolution of the North American continent and (2) contributing to the mitigation of risks from geological hazards. Pacific-North American plate motion is not limited to California's San Andreas fault system. It also encompasses the Great Basin physiographic province which is characterized by Basin and Range style deformation and encompasses an area reaching 800 km in width between about Reno, NV to the west and Salt Lake City, UT to the east. The Great Basin is one of the world's type-examples of diffuse continental extension. This field study is aimed to quantify the late-Pleistocene occurrence of earthquake displacements (paleoseismology) on major range-bounding active faults across the interior of the Great Basin. The locations of the studies are along an anticipated Earthscope-deployment of Geographic Position System instruments that will form a dense array across the Great Basin. The motivation for the field study stems from the understanding that the kinematics and mechanics of the North-American plate boundary will require measurements of the rate, style, and evolution of deformation across the entirety of the boundary through geologic time. Thus while Earthscope-Plate Boundary Observatory Geographic Position System instruments are measuring strain accumulation, our study is measuring how that strain is released. The knowledge we are gaining is being used to understand the physics of the earthquake process, the development of the structure and physiography across the western United States, and the contemporary strain signal itself. Additionally, the research is supporting the education of a Ph.D. student, and study sites are being used in University field classes as introductions to research methods. It is also intended that this work to understand the physics of the earthquake process will be incorporated into efforts to define seismic hazards and forecast the locations and sizes of future earthquakes.