コンビーナ:佐藤 比呂志(東京大学地震研究所地震予知研究センター)、David A Okaya(University of Southern California)、Eh Tan(Institute of Earth Sciences, Academia Sinica)、石川 正弘(横浜国立大学大学院環境情報研究院)

Subduction over time modifies the overriding plate by fractionation, accretion, and tectonic deformation. This can lead to processes such as tectonic shortening (orogeny), regional uplift, weakening by back-arc spreading and volcanism, basin formation, and/or destabilization of the lithosphere. In turn, the composition, strength, and morphology of the overlying plate, which may be the product of a long geological history and have significant along-strike variations, can affect current large-scale subduction dynamics such as slab dip, and ultimately broad-scale plate kinematics in two and three dimensions. Examples of geological settings that bear witness to these processes are found along the Pacific Rim, including Japanese arcs, Taiwan, Hikurangi, northwestern North America, and Tethys margin, including Himalaya and the Mediterranean mobile belt. We seek contributions from all geoscience disciplines that document the structure and tectonic evolution of overlying plate deformation and their feedbacks onto subduction processes. We welcome studies on topics such as: geologic and tectonic geomorphological deformation of the overlying plate and its relation to the subduction; geodetic deformation of the overlying plate; active and passive imaging of the overlying plate and crustal structure; rheological features obtained by laboratory and earthquake seismology; basin development and mountain building processes; numerical geodynamical modeling of overlying plate deformation; and backarc opening proceses. Comparisons of the Nankai and Japan Trench subduction systems to other global subduction zones are of particular interest. This session is supported by ILP (International Lithosphere Program).