JpGU-AGU 2020 meeting session of interest

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 processes. 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).

Conveners:

Hiroshi Sato, Univ Tokyo/ERI, Japan

David Okaya, Univ. Southern California, USA

Eh Tan, Academia Sinica, Taiwan

Masahiro Ishikawa, Yokohama National University, Japan