Japan Geoscience Union Meeting 2016

Presentation information


Symbol M (Multidisciplinary and Interdisciplinary) » M-TT Technology & Techniques

[M-TT27] New frontier of data analysis in geoscience: Data-driven approach

Sun. May 22, 2016 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall HALL6)

Convener:*Tatsu Kuwatani(Japan Agency for Marine-Earth Science and Technology), Takeshi Komai(none), Hideaki Miyamoto(The University Museum, The University of Tokyo), Katsuaki Koike(Laboratory of Environmental Geosphere Engineering, Department of Urban Management, Graduate School of Engineering, Kyoto University), Takane Hori(R&D Center for Earthquake and Tsunami, Japan Agency for Marine-Earth Science and Technology), Hiromichi Nagao(Earthquake Research Institute, The University of Tokyo)

5:15 PM - 6:30 PM

[MTT27-P01] Classification of sediments in the Nankai Trough accretionary prism by Principal Component Analysis

*Kuniyo Kawabata1, Yujin Kitamura2 (1.The Kagoshima University Museum, 2.Graduate School of Science and Engineering, Kagoshima University)

Keywords: the Nankai Trough accretionary prism, Chemical composition, Principal Component Analysi

The Nankai Trough has been studied extensively for understanding the plate boundary process as the society is threatened by upcoming great earthquake. Nankai Trough Seismogenic Zone Experiments (NanTroSEIZE) in the framework of the Integrated Ocean Drilling Program (IODP) have been obtained seismological and geological data from direct sampling and in-situ measurement by drilling into the shallow accretionary prism. The feature of sediments forming the accretionary prism have been figured out based on analyses of drilled core and drill cuttings. Classification of the sediments by defining lithological units has been performed by mainly synthesis of observational results and log data. Analyses of mineral and chemical composition and gas composition were also important auxiliary data.
Here we try to classify the sediments based on the chemical composition using Principal Component Analysis (PCA), and estimate chemical processes relate to the depositional and diagenetic process of sediments and the formation process of the accretionary prism. We used major chemical compositions data of 6 IODP drill sites situated in Kumano forearc Basin, Slope sediment, Frontal thrust zone and Subduction input in the Nankai accretionary prism. The PCA results show that the sediments from the Kumano forearc Basin and accretionary prism were obviously distinguished in terms of chemical composition. Classification of the sediments is firstly sensitive to LOI, CaO and SiO2 contents, and secondary relate to metallic elements such as MgO, Fe2O3 and TiO2. It implies that the abundance in LOI and CaO is linked to diagenesis of sediments, and so does metallic components to their depositional source.