Japan Geoscience Union Meeting 2014

Presentation information

Print

Oral

Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS32_30AM1] Drilling Earth Science

Wed. Apr 30, 2014 9:00 AM - 10:45 AM 416 (4F)

Convener:*Saneatsu Saito(Japan Agency for Marine-Earth Science and Technology), Ken Ikehara(Institute of Geology and Geoinformation, National Institute of Advanced Industrial Science and Technology), Tetsuro Hirono(Department of Earth and Space Science, Graduate School of Science, Osaka University), Keita Umetsu(Japan Agency for Marine-Earth Science and Technology), Chair:Arito Sakaguchi(Yamaguchi Univ.), Junichiro Kuroda(Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology)

9:15 AM - 9:30 AM

[MIS32-02] Ultra-deep riser drilling into the Nankai accretionary prism: Preliminary results of IODP Expedition 348

*Takehiro HIROSE1, Harold TOBIN2, Demian SAFFER3, Sean TOCZKO1, Lena MAEDA1, Yusuke KUBO1, Kyuichi KANAGAWA4, Gaku KIMURA4, EXPEDITION 348, Scientists 5 (1.JAMSTEC, 2.University of Wisconsin-Madison, 3.Pennsylvania State University, 4.Chiba University, 5.IODP Expedition 348)

Keywords:IODP, NanTroSEIZE, Nankai Trough, accretionary prism

The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is a multi-disciplinary scientific project designed to investigate fault mechanics and seismogenesis along subduction megathrusts through seismic imaging, direct sampling, in situ measurements, and long-term monitoring in conjunction with laboratory and numerical modeling studies. As part of the NanTroSEIZE program, International Ocean Discovery Program (IODP) Expedition 348 started on 13 September 2013 and was completed on 29 January 2014. During Expedition 348, the drilling vessel Chikyu advanced the ultra-deep riser hole at Site C0002, located 80 km offshore from the Kii Peninsula, from a depth of 860 meters below sea floor (mbsf) to 3058.5 mbsf, the world record for the deepest scientific ocean drilling, and cased it for future access. The drilling operation successfully obtained data on formation physical properties from logging while drilling (LWD) tools, as well as from lithological analyses of cuttings and core from the interior of the active accretionary prism at the Nankai Trough. IODP Site C0002 is the currently only borehole to access the deep interior of an active convergent margin. We will present preliminary scientific results as well as key aspects of riser-drilling operations, including two sidetrack borehole drilling operations conducted in this never-before accessed tectonic environment.