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

沿着横跨大盆地内部的 Earthscope-PBO 密集 GPS 站阵列进行古地震学研究

• 批准号: 0509672
• 负责人: Steven Wesnousky
• 金额: $ 30.31万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0509672&HistoricalAwards=false
• 关键词: Paleoseismology; along; Earthscope; PBO; Dense

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.

美国西部和太平洋-北美板块边界现在是国家科学基金会赞助的主要倡议“地球镜”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调查北美大陆的结构和演变;（2）帮助减轻地质灾害的风险。太平洋-北美板块的运动并不局限于加州的圣安德烈亚斯断层系统。它还包括大盆地自然地理省，其特征是盆地和山脉式变形，包括西部内华达州里诺和东部犹他湖城之间宽度达800 km的区域。大海盆是世界上分散大陆伸展的典型例子之一。这项实地研究的目的是量化晚更新世发生的地震位移（古地震学）的主要范围界定活动断层在大盆地内部。研究的地点是沿着一个预期的地球定位系统仪器，将形成一个密集的阵列在大盆地部署。实地研究的动机源于对北美板块边界的运动学和力学的理解，这将需要测量整个地质时期边界的变形速率、样式和演变。因此，当地球板块边界观测站地理定位系统仪器测量应变积累时，我们的研究正在测量应变是如何释放的。我们获得的知识被用来了解地震过程的物理学，美国西部的结构和自然地理学的发展，以及当代应变信号本身。此外，该研究还支持博士教育。学生和研究地点被用于大学的野外课程，作为研究方法的介绍。还打算将这项了解地震过程物理学的工作纳入界定地震危险和预测未来地震的地点和规模的工作中。