| 英文摘要: | 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. |