Southern California Earthquake Center: Research Program in Earthquake System Science, 2017-2022

该合作协议资助南加州地震中心（SCEC），为期5年，从2017年2月1日至2022年1月31日（SCEC5）。该中心是一个大型机构联盟，分布在全国各地，并日益扩大到世界各地。目前，有1000多名地震专业人员参与了SCEC项目。该研究项目由研究人员主导，支持地震学、构造大地测量学、地震地质学和计算科学的核心研究和教育。SCEC社区通过收集地震和大地测量传感器、地质现场观测和实验室实验的信息来推进地震系统科学；通过系统级、基于物理的建模综合地震现象知识；传播对地震灾害的认识，以减少地震风险，促进社区恢复能力。南加州数据丰富，城市化人口超过2000万，是全国地震风险最大的地区。最近的研究对圣安德烈亚斯断层系统当前的地震危险提出了关键问题。SCEC5科学计划的战略框架以地震科学的五个基本问题的形式呈现：(1)断层在不同的时空尺度上是如何负荷的？(2)离断层非弹性变形对应变积累、动力破裂和辐射地震能量的作用是什么？(3)断裂带和围岩的构造、组成和物理性质的演化如何影响其抗地震和地震滑动的剪切能力？(4)强地震动如何依赖于动力地震系统的复杂性和非线性？(5)针对系统的研究可以通过哪些方式增强对地震可预见性的一般认识？这些问题涵盖了推动加州地震研究的关键问题，它们为衡量拟议的SCEC5研究活动的智力价值提供了基础。SCEC的长期科学愿景是开发地震过程的动力学模型，这些模型是全面的、综合的、经过验证的、可预测的，并根据观测结果进行验证。SCEC5核心项目的科学目标是提供可以提高地震系统模型可预测性的新概念，测试模型的新数据，以及更好地理解模型的不确定性。SCEC验证工作将基础地震研究与概率地震危害分析、业务地震预报、地震早期预警和快速地震响应的实际需求紧密结合起来。此外，降低风险的问题？这需要由有用信息驱动的行动？地震力学与地震工程紧密结合。SCEC与工程组织的合作面向端到端、基于物理的建模能力，涵盖从断裂到椽子的系统过程。SCEC通过其向利益相关者传达权威信息的使命与社会科学相联系，从而降低风险并增强复原力。SCEC的愿景是让最终用户和广大公众参与以社区为中心的持续对话，讨论如何通过采取具体行动来管理特定风险。SCEC的沟通、教育和外联项目将在多个层面上促进这种对话，并继续建立组织合作伙伴网络，使各年龄层和社会经济阶层的数百万人为不可避免的地震灾害做好准备。

This cooperative agreement funds the Southern California Earthquake Center (SCEC) for the 5-year period from 1 Feb 2017 to 31 Jan 2022 (SCEC5). The Center is a large consortium of institutions with a national, and increasingly worldwide, distribution. Currently, over 1000 earthquake professionals are participating in SCEC projects. This research program is investigator-driven and supports core research and education in seismology, tectonic geodesy, earthquake geology, and computational science. The SCEC community advances earthquake system science by gathering information from seismic and geodetic sensors, geologic field observations, and laboratory experiments; synthesizing knowledge of earthquake phenomena through system-level, physics-based modeling; and communicating understanding of seismic hazards to reduce earthquake risk and promote community resilience. Southern California is data-rich and, with an urbanized population exceeding 20 million, comprises the lion's share of national earthquake risk. Recent research has posed crucial questions about the current earthquake hazard of the San Andre-as fault system. The strategic framework for the SCEC5 Science Plan has been cast in the form of five basic questions of earthquake science: (1) How are faults loaded on different temporal and spatial scales? (2) What is the role of off-fault inelastic deformation on strain accumulation, dynamic rupture, and radiated seismic energy? (3) How do the evolving structure, composition and physical properties of fault zones and surrounding rock affect shear resistance to seismic and aseismic slip? (4) How do strong ground motions depend on the complexities and nonlinearities of dynamic earthquake systems? (5) In what ways can system-specific studies enhance the general understanding of earthquake predictability? These questions cover the key issues driving earthquake research in California, and they provide a basis for gauging the intellectual merit of proposed SCEC5 research activities. SCEC's long-range science vision is to develop dynamical models of earthquake processes that are comprehensive, integrative, verified, predictive, and validated against observations. The science goal of the SCEC5 core program is to provide new concepts that can improve the predictability of the earth-quake system models, new data for testing the models, and a better understanding of model uncertain-ties. SCEC validation efforts tightly couple basic earthquake research to the practical needs of probabilistic seismic hazard analysis, operational earthquake forecasting, earthquake early warning, and rapid earthquake response. Moreover, the risk-reduction problem?which requires actions motivated by useful information?strongly couples SCEC science to earthquake engineering. SCEC collaborations with engineering organizations are directed towards end-to-end, physics-based modeling capabilities that span system processes from ?ruptures-to-rafters.? SCEC connects to the social sciences through its mission to convey authoritative information to stakeholders in ways that result in lowered risk and enhanced resilience. SCEC's vision is to engage end-users and the public at large in on-going, community-centric conversations about how to manage particular risks by taking specific actions. The SCEC Communication, Education, and Outreach (CEO) program will promote this dialog on many levels and continue to build networks of organizational partners that can act in concert to prepare millions of people of all ages and socioeconomic levels for inevitable earthquake disasters.