New GPS Constraints on Africa-Arabia-Eurasia Plate Kinematics

GPS 对非洲-阿拉伯-欧亚大陆板块运动学的新约束

• 批准号: 1450922
• 负责人: Robert King
• 金额: $ 17.5万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1450922&HistoricalAwards=false
• 关键词: New; GPS; Constraints; Africa; Arabia

The active plate boundary interactions in the Mediterranean are complex and pose significant earthquake hazards for the populations living in that region. In this study, MIT researchers in conjunction with a large multi-national team will carry out analyses of GPS data, which track the directions and speeds of the plates, for this region that have been collected over the past 20 years in an effort to better understand the plate interactions in this region as well as the motion of earthquake generating faults such as the North Anatolian fault. The range of active geodynamic processes that characterize this plate system (continental collision, subduction/slab rollback, lithospheric delamination, continental transform faults and triple junctions, volcanism, ocean and continental rifting), when studied through the lens of the new GPS data, affords new insights into active continental tectonics with broader implications for earthquake, tsunami, and volcanic natural hazards. The potential for the proposed activity to benefit society or advance desired societal outcomes lies primarily in the following: (1) improved well-being of individuals in society through improved basis of earthquake hazard estimation along the Africa-Arabia-Eurasia plate boundary system; (2) increased partnerships through a substantial international collaboration; and (3) enhanced infrastructure for research by archiving a large amount of data from international partner data in the UNAVCO database for open access.In collaboration with many international institutions, a new secular velocity field for the Africa-Arabia-Eurasia plate system based on continuous and survey observations for the period 1994-2014 has been generated. The velocity field includes major densification and improved resolution around active structures (North and East Anatolian, Dead Sea, and Main Caucasus Thrust faults, Hellenic arc, Gulf of Corinth rift, Zagros Fold and Thrust belt, Red Sea, Gulf of Aden, and East African rifts, Danakil and Afar depression) and areas characterized by low internal strain rates (East Turkey/Iranian High Plateau, central Anatolia, south-central Aegean/Peloponnese, Arabian Plate). This project, carried in collaboration with researchers from France, Turkey, and Australia, utilizes this new velocity to explore the behavior of various components of the Arabia-Africa-Eurasia plate system. Research on the Aegean and western/central Anatolia deformation focuses on block and continuum deformation models, and estimating slip rates on major faults. Work on the North Anatolian fault slip rates and locking depths will provide improved constraints on slip rates and locking depths along the full, approximately 1200 km extent of the fault and constrain possible variations in rates and locking depths that may be related to the time since the last earthquake, and/or spatial variations in other fault characteristics. Finally, study of Africa-Arabia-Eurasia intra- and inter-plate deformation and dynamics investigates kinematic models for the system. The full data set used for the 1994-2014 velocity field plus any new observations will be archived in the UNAVCO database for open access.

地中海活跃的板块边界相互作用是复杂的，对生活在该地区的居民构成重大地震危险。在这项研究中，麻省理工学院的研究人员将与一个大型多国团队一起，对过去20年来收集的该地区跟踪板块方向和速度的GPS数据进行分析，以努力更好地了解该地区的板块相互作用以及北安纳托利亚断层等地震发震断层的运动。当通过新的GPS数据的透镜研究该板块系统的一系列活动地球动力学过程(大陆碰撞、俯冲/板条退回、岩石圈拆沉、大陆转换断层和三重接合、火山作用、海洋和大陆裂谷)时，可以对活动大陆构造提供新的见解，对地震、海啸和火山自然灾害具有更广泛的影响。拟议活动造福社会或推动预期社会成果的潜力主要在于：(1)通过改进非洲-阿拉伯-欧亚板块边界系统地震危险估计的基础，改善社会个人的福祉；(2)通过大量的国际合作增加伙伴关系；(3)通过将来自国际伙伴的大量数据归档到联安办事处数据库以供开放查阅，加强研究基础设施。速度场包括活动构造(北安纳托利亚和东安纳托利亚、死海和主要高加索逆冲断层、希腊弧形、科林斯湾裂谷、扎格罗斯褶皱和冲断带、红海、亚丁湾和东非裂谷、达纳基尔和阿法尔凹陷)以及以内部应变率低为特征的地区(土耳其东部/伊朗高高原、安纳托利亚中部、爱琴海中南部/伯罗奔尼撒板块、阿拉伯板块)周围的主要致密化和提高的分辨率。这个项目是与法国、土耳其和澳大利亚的研究人员合作进行的，利用这种新的速度来探索阿拉伯-非洲-欧亚板块系统的各种组成部分的行为。对爱琴海和安纳托利亚西部/中部变形的研究主要集中在块体和连续变形模型，以及主要断裂上的滑动速率估计。关于北安纳托利亚断层滑动速率和锁定深度的工作将改善对整个断层约1200公里范围内滑动速率和锁定深度的约束，并限制可能与上次地震以来的时间有关的速率和锁定深度的变化，和/或其他断层特征的空间变化。最后，对非洲-阿拉伯-欧亚板块内和板块间的变形和动力学进行了研究，探讨了该系统的运动学模型。1994-2014年速度场所用的全部数据集以及任何新的观测数据都将存档在联安部队数据库中，以供开放使用。