EAR-PF: Dynamic Rupture Modeling on Major San Andreas Fault Intersections

Julian C. Lozos博士获得了美国国家科学基金会地球科学博士后奖学金，在斯坦福大学和美国地质调查局门洛帕克校区开展研究和推广计划。该项目旨在提高我们对物理过程的理解，这些物理过程决定了地震破裂如何在主要断层之间协商连接，并通过扩展，我们对断层分割的理解。Lozos博士将进行动态破裂模型，为圣安德烈亚斯断层和其他三个断层（分别是圣哈辛托断层、加洛克断层和卡拉维拉斯断层）之间的连接处制造一套情景地震。这些连接点中的每一个都代表着不同类型的几何、地质和应力复杂性，并且每一个都对其周围地区构成重大的地震危险。因此，对圣安德烈亚斯系统的关注将提高对一般断层物理的理解，以及对加州地震危险的理解。以前的研究主要集中在这些断层上，或者集中在这些连接所代表的几何类型的概括和简化上。本研究将通过将许多类型的复杂性纳入模型输入，对研究区域进行更现实和详细的建模。复杂的断层几何形状、速度结构和初始应力将通过断层地质学和地震活动文献以及静态应力建模来了解。一旦情景建模完成，Lozos博士将把结果与古地震和历史数据进行比较，既约束建模结果与已知的过去断层行为，又提供对过去这些断层交界处地震的大小和程度的洞察。许多人居住在研究区域附近，因此，该项目包括一个教育和推广计划，重点是向公众宣传地震的基本科学知识、相关危害以及如何做好准备。洛佐斯博士将在他研究区域附近的社区进行一系列公开演讲。通过斯坦福大学，他将帮助带领K-12学生到当地断层带进行实地考察，并通过美国地质勘探局，他将参加额外的公共宣传活动。除了公共宣传外，Lozos博士还将协助斯坦福大学开发断层物理学的研究生课程，这将有助于他为未来的学术生涯做好准备。

Dr. Julian C. Lozos has been granted a NSF Earth Sciences Postdoctoral Fellowship to carry out a research and outreach plan at Stanford University and the USGS Menlo Park campus. This project aims to improve our understanding of the physical processes that determine how seismic rupture negotiates a junction between major faults, and by extension, our understanding of fault segmentation. Dr. Lozos will conduct dynamic rupture models to produce a suite of scenario earthquakes for the junctions between the San Andreas Fault and three other faults: the San Jacinto Fault, the Garlock Fault, and the Calaveras Fault respectively. Each of these junctions represents different types of geometrical, geological, and stress complexity, and each poses a significant seismic hazard to its surrounding area. Thus, the focus on the San Andreas system will improve understanding of general fault physics, as well as of seismic hazard in California. Previous studies have focused on these faults individually, or on generalizations and simplifications of the types of geometries represented by these junctions. This study will consist of more realistic and detailed modeling of the study areas, by incorporating many types of complexity into the model inputs. Complex fault geometry, velocity structure, and initial stresses will be informed by fault geology and seismicity literature, as well as by static stress modeling. Once the scenario modeling is completed, Dr. Lozos will compare the results to paleoseismic and historical data, both to constrain the modeling results against known past fault behavior, and to provide insight into the sizes and extents of earthquakes at these fault junctions in the past. Many people live in the vicinity of the study areas, and thus, this project includes an education and outreach program focused on informing the public of the basic science of earthquakes, the related hazard, and on how to prepare for them. Dr. Lozos will give a series of public talks in communities near his study areas. Through Stanford, he will help lead field trips for K-12 students to local fault zones, and through the USGS, he will participate in additional public outreach events. In addition to public outreach, Dr. Lozos will also assist in developing a graduate-level course on fault physics at Stanford, which will help prepare him for a future career in academia.