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发起的主要倡议Earthscope的重点，该倡议主要旨在(1)利用现代观测技术，如全球定位系统和地震仪器来调查北美大陆的结构和演变；(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州的圣安德烈亚斯断层系统。它还包括以盆地和山脉类型变形为特征的大盆地地理省，包括西部内华达州里诺市和东部犹他州盐湖城之间宽度达800公里的地区。大盆地是世界上弥漫性大陆伸展的典型例子之一。本研究旨在量化大盆地内部主要活动断层晚更新世地震位移（古地震学）的发生情况。这些研究的地点沿着预期的地球范围部署地理定位系统仪器，这些仪器将在大盆地形成密集的阵列。实地研究的动机源于这样一种认识，即北美板块边界的运动学和力学将需要通过地质时间测量整个边界的变形速率、样式和演化。因此，当地球镜-板块边界观测站地理位置系统仪器测量应变积累时，我们的研究是测量应变如何释放。我们所获得的知识正在被用来理解地震过程的物理学，美国西部的结构和地形的发展，以及当代应变信号本身。此外，这项研究支持博士生的教育，研究地点被用于大学实地课程，作为研究方法的介绍。我们还打算将这项了解地震过程的物理学的工作纳入定义地震危害和预测未来地震的位置和大小的工作中。

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.