Collaborative Research: Understanding Fault Zone Compliance by Seismic Probing of InSAR Anomalies

合作研究：通过 InSAR 异常地震探测了解断层带顺应性

• 批准号: 0440005
• 负责人: Yong-Gang Li
• 金额: $ 14.47万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0440005&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; Fault; Zone

This project aims to measure how much weaker are the rocks in fault zones than the surrounding, unbroken rocks. The consortium of institutions will deploy seismometers to record explosions and earthquakes. The experiment will first decipher the structure of the crust in terms of P, S, and surface wave speeds, then interpret the wavespeed maps in terms of rock strength and crack density. The group will also measure the ground deformation over several years with GPS. These structures will be compared with the features noted with satellite deformation monitoring. The insights gatheredwill help understand why fault systems form as they do. More specifically, the spacing of faults and the frequency of earthquakes across the fault system in California is ripe for a deeper understanding, and this project will strive for progress in this direction.The investigators propose to integrate the expertise at UCLA, UCSD, and USC to systematically map the structural cross-section of the Calico and Pinto Mountain fault zones across profiles that exhibited anomalous strain in response to the Landers and Hector Mine earthquakes. They will deploy portable seismographs in both an active-source experiment to map the shallow fault structure and a passive-source experiment to image deeper structure. Their observations will test and extend previous InSAR modeling to better resolve the amplitude, width and depth of fault zone anomalies. This project will explore the structure and evolution of seismogenic faults in the Mojave using a variety of methods. The results will constrain the size of fault zone weakness and variations in strength across the earthquake cycle and lead to improved understanding of fault mechanics.This project supports educational programs at three universities, including graduate student research and field programs for undergraduates. Collaboration between institutions will be promoted by regular meetings of the PIs, students and postdocs to discuss relevant science and the state of the project. Results of this research will be widely disseminated through publications, conference presentations and media contacts, including a project website. This research will provide a better understanding of fault behavior, leading eventually to improved earthquake forecasting and reduced casualties and damage.

该项目旨在测量断层带中的岩石比周围未破碎的岩石脆弱多少。 该机构联盟将部署地震仪来记录爆炸和地震。 该实验将首先根据 P、S 和表面波速解读地壳结构，然后根据岩石强度和裂缝密度解释波速图。该小组还将使用 GPS 测量数年的地面变形。 这些结构将与卫星变形监测记录的特征进行比较。 收集到的见解将有助于理解断层系统为何形成。 更具体地说，对加州断层系统的断层间距和地震频率进行更深入的了解已经成熟，该项目将努力在这个方向上取得进展。研究人员建议整合加州大学洛杉矶分校、加州大学圣地亚哥分校和南加州大学的专业知识系统地绘制了卡利科和平托山断层带的结构横截面图，这些断层带在响应兰德斯和赫克托矿地震时表现出异常应变。 他们将在主动源实验中部署便携式地震仪来绘制浅层断层结构图，并在被动源实验中部署更深层次的结构图像。他们的观测结果将测试和扩展之前的 InSAR 模型，以更好地解决断层带异常的幅度、宽度和深度。该项目将采用多种方法探索莫哈韦地震断层的结构和演化。研究结果将限制断层带弱点的大小和整个地震周期的强度变化，并提高对断层力学的理解。该项目支持三所大学的教育项目，包括研究生研究和本科生实地项目。 PI、学生和博士后定期举行会议讨论相关科学和项目状况，将促进机构之间的合作。这项研究的结果将通过出版物、会议演示和媒体联系（包括项目网站）广泛传播。 这项研究将更好地了解断层行为，最终改善地震预报并减少人员伤亡和损失。