Solid Earth Sciences (S)
Session Sub-categorySeismology (SS)
Session IDS-SS06
TitleNankai Trough Seismogenic Zone Experiment: Logging and sampling the seismogenic megathrust
Short TitleNanTroSEIZE
Main Convener NameKyuichi Kanagawa
AffiliationGraduate School of Science, Chiba University
Co-Convener 1NameDemian M Saffer
AffiliationPennsylvania State University
Co-Convener 2NameMasataka Kinoshita
AffiliationEarthquake Research Institute, University of Tokyo
Session LanguageE
ScopeThe Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is a multidisciplinary investigation of fault mechanics and seismogenesis along the megathrust at the Nankai Trough subduction zone, and includes reflection and refraction seismic imaging, direct sampling by drilling, in situ measurements, and long-term monitoring in conjunction with laboratory and numerical modeling studies. During the past 12 IODP expeditions off Kii Peninsula since 2007, 15 sites have been drilled by D/V "Chikyu" down to depths from 100s of meters to more than 3000 meters below seafloor, where the inner and outer wedge of the Nankai margin has been logged and sampled extensively, and three state-of-the-art real-time downhole observatories are now in operation. The final NanTroSEIZE expedition aiming to log and sample the seismogenic megathrust at ~5200 meters below seafloor is now ongoing from October, 2018 to March, 2019.
In this session, we expect presentations not only on scientific outcomes from the past NanTroSEIZE expeditions, but also on the exciting preliminary results of the final NanTroSEIZE expedition. We welcome presentations on, but are not limited to, seismic imaging, borehole logging and monitoring, chemical analyses of pore water and mud gas, lithology, structures, physical properties and laboratory experiments of cuttings and core samples, and theoretical and numerical modeling.
Presentation FormatOral and Poster presentation
Invited AuthorsHarold Tobin (Department of Earth and Space Sciences, University of Washington)
Yusuke Yokota (Institute of Industrial Science, The University of Tokyo)
Yohei Hamada (Japan Agency for Marine-Earth Science and Technology Kochi Institute for Core Sample Research)
TimePresentation NoTitlePresenterAbstract
Oral Presentation May 28 PM1
13:45 - 14:00SSS06-01Geoscientific information about plate boundary along the Nankai Trough provided by the GNSS-AYusuke Yokota
14:00 - 14:15SSS06-02Deep Drilling at the Nankai Trough: IODP NanTroSEIZE Expedition 358 Summary and First ResultsHarold Tobin
14:15 - 14:30SSS06-03Coexistence of soft and hard sediments at deep Nankai accretionary prism, NanTro SEIZE Project, IODP Exp.358Arito Sakaguchi
14:30 - 14:45SSS06-04Active and passive seismic experiment during the IODP Exp. 358 deep riser drilling in the Nankai Trough, JapanToshinori Kimura
14:45 - 15:00SSS06-05Microfabric analysis of damaged zone of principal shear zone in the frontal megathrust in the Nankai TroughGaku Kimura
15:00 - 15:15SSS06-06Seismic Imaging of Mud Diapirs in Northern Kumano Basin, Nankai TroughGregory F Moore
Presentation NoTitlePresenterAbstract
Poster Presentation May 28 PM2
SSS06-P01Crustal structure in the Nankai Trough seismogenic zone based on renewed depth images and seismic attribute analysisKazuya Shiraishi
SSS06-P02Along-strike variations in protothrust zone characteristics at the Nankai Trough subduction marginHannah Tilley
SSS06-P03Temporal change in seismic velocity in the Nankai subduction zone from cross-correlation analysis of ambient noiseTatsunori Ikeda
SSS06-P04Strength profile of the Nankai accretionary prism evaluated from drilling parametersYohei Hamada
SSS06-P05Paleotemperature anomalies deduced from thermal-maturity parameters within the décollement, off Cape of Muroto, JapanNana Kamiya
SSS06-P06Modelling thermal maturity of an accretionary wedgeMasataka Kinoshita