Landslide Process Revealed by Mineralogical Properties of Landslide Deposits in the Sa Pa District, Vietnam
Takanari Yamasaki*1, Go Sato*1,, Takashi Kimura*2, Hoang Viet Hung*3, Nguyen Duc Manh*4, Takatsugu Ozaki*5, Osamu Yokoyama*6, Shinichi Tosa*6, and Akihiko Wakai*5
*1Graduate School of Environmental Informations, Teikyo Heisei University
4-21-2 Nakano, Nakano-ku, Tokyo 164-8530, Japan
*2Graduate School of Agriculture, Ehime University, Ehime, Japan
*3Faculty of Civil Engineering, Thuyloi University, Hanoi, Vietnam
*4Department of Geotechnical Engineering, University of Transport and Communications, Hanoi, Vietnam
*5Graduate School of Science and Technology, Gunma University, Gunma, Japan
*6Japan Conservation Engineers & Co., Ltd., Tokyo, Japan
Hau Thao Village is located in Sa Pa Prefecture, in northern Vietnam. The village contains one of the most picturesque landscapes with terraced paddy fields located in landslide topography formed on a gentle slope. However, the creation of the topography has not been sufficiently clarified. In this study, samples of soil and stone are taken from two landslide areas in Hau Thao Village for mineral composition analysis, clarifying that the sauce rock of the deposits comprising the landslide areas is made up of granitoids, forming the upper slope above the fault located in the hinterland. The landslides occurring in Hau Thao Village are caused by the remobilization of the secondary deposits transported from the upper part of the slope by debris flow.
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