HR: 1340h
AN: T43A-1367    [Abstracts]
TI: DEM Simulated Results And Seismic Interpretation of the Red River Fault Displacements in Vietnam
AU: * BUI, H T
EM: huyen@earth.kumst.kyoto-u.ac.jp
AF: Engineering Geology Laboratory, Dept. of Civil and Earth Resources Engineering, Kyoto Univ., Yoshida Hon-machi, Sakyo-ku, Kyoto, 6068501 Japan
AU: YAMADA, Y
T43A-1367 AF: Engineering Geology Laboratory, Dept. of Civil and Earth Resources Engineering, Kyoto Univ., Yoshida Hon-machi, Sakyo-ku, Kyoto, 6068501 Japan
AU: MATSUOKA, T
T43A-1367 AF: Engineering Geology Laboratory, Dept. of Civil and Earth Resources Engineering, Kyoto Univ., Yoshida Hon-machi, Sakyo-ku, Kyoto, 6068501 Japan
AB: The Song Hong basin is the largest Tertiary sedimentary basin in Viet Nam. Its onset is approximately 32 Ma ago since the left-lateral displacement of the Red River Fault commenced. Many researches on structures, formation and tectonic evolution of the Song Hong basin have been carried out for a long time but there are still remained some problems that needed to put into continuous discussion such as: magnitude of the displacements, magnitude of movement along the faults, the time of tectonic inversion and right lateral displacement. Especially the mechanism of the Song Hong basin formation is still in controversy with many different hypotheses due to the activation of the Red River fault. In this paper PFC2D based on the Distinct Element Method (DEM) was used to simulate the development of the Red River fault system that controlled the development of the Song Hong basin from the onshore to the elongated portion offshore area. The numerical results show the different parts of the stress field such as compress field, non-stress field, pull-apart field of the dynamic mechanism along the Red River fault in the onshore area. This propagation to the offshore area is partitioned into two main branch faults that are corresponding to the Song Chay and Song Lo fault systems and said to restrain the east and west flanks of the Song Hong basin. The simulation of the Red River motion also showed well the left lateral displacement since its onset. Though it is the first time the DEM method was applied to study the deformation and geodynamic evolution of the Song Hong basin, the results showed reliably applied into the structural configuration evaluation of the Song Hong basin.
DE: 8111 Continental tectonics: strike-slip and transform
SC: Tectonophysics [T]
MN: Fall Meeting 2005