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

该项目旨在测量断裂带中的岩石比周围未破碎的岩石脆弱多少。这个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和表面波速度破译地壳结构，然后根据岩石强度和裂缝密度解释波速图。该小组还将用GPS测量几年来的地面变形。这些结构将与卫星变形监测所记录的特征进行比较。所收集的见解将有助于理解断层系统形成的原因。更具体地说，断层的间距和加利福尼亚断层系统的地震频率已经成熟，可以更深入地了解，这个项目将努力朝着这个方向取得进展。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Calico和Pinto山断裂带的结构横截面，这些断裂带在兰德斯和赫克托矿地震中表现出异常应变。他们将在一个主动震源实验中部署便携式地震仪来绘制浅层断层结构，在一个被动震源实验中部署便携式地震仪来绘制深层断层结构。他们的观测结果将测试和扩展以前的InSAR模型，以更好地解决断裂带异常的幅度、宽度和深度。该项目将使用多种方法探索莫哈韦地震发震断层的结构和演化。研究结果将限制断裂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。通过pi、学生和博士后的定期会议，讨论相关科学和项目进展，促进机构之间的合作。这项研究的结果将通过出版物、会议发言和媒体接触，包括项目网站，广泛传播。这项研究将提供对断层行为的更好理解，最终导致改进地震预报，减少人员伤亡和损失。

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.