tailieunhanh - Some study results of Cam Ranh - Binh Thuan mud eruption strip

The research should help understand more clearly the nature of the mud eruption in order to provide the local decision-makers with reasonable solutions for hazard mitigation, on the one hand, and effective use of the mud materials, on the other. | Vietnam Journal of Earth Sciences 38(3), 256-276 Vietnam Academy of Science and Technology Vietnam Journal of Earth Sciences (VAST) Some study results of Cam Ranh - Binh Thuan mud eruption strip Bui Van Thom*1, Phan Trong Trinh1, Ngo Tuan Tu2, Nguyen Anh Duong1, Nguyen Dang Manh1 1 Institute of Geological Sciences, Vietnam Academy Science and Technology 2 Division of planning and investigation of water resources in central region Received 25 April 2016. Accepted 11 June 2016 ABSTRACT Most of the mud eruption locations are distributed in a stretching strip, running in NE-SW direction from Cam Ranh - Ninh Thuan - Binh Thuan NE-SW tectonic fault zone and coinciding with a tectonically crushed zone. The erupted mud consists of sand, mud, clay. The clay contains alkaline montmorillonite, formed following chemical weathering and re-sedimentation processes from rocks containing alkaline minerals in a semi-arid climate area, located in a low terrain or a tectonic subsiding zone with a large fluctuation in groundwater level. The mud eruption has a close relation to factors (of) climate, topography, geomorphology, hydrogeology, , petrography and tectonic activities in the area. Among these, tectonic factors are the most important for they create not only soil and rock crushed zone, paving favorable conditions for strong weathering process at depth, but also to form canals to bring hot groundwater and minerals from certain depths upward, and by the effects of pressurized groundwater and partly due to the expansion in volume of bentonite clay pushing the muddy clay material through the tectonic cracks to the surface of the current terrain. The mud eruption process is not deep; but it may occur from a shallow level, about 418 m below, under the impact of the above elements. Keywords: Mud eruption; bentonite clay; tectonic fault zone; Ninh Thuan mud eruption. ©2016 Vietnam Academy of Science and Technology 1. Introduction* In recent .