ASSESSING SUBMARINE LANDSLIDE STATUS BY USING SEABED TOPOGRAPHY 3D MODEL AND FAULT STRUCTURE ON SOUTH CENTRAL VIETNAM’S CONTINENTAL SHELF

Phi Truong Thanh, Tran Tuan Dung

Abstract


This paper presents some results of assessing submarine landslide status by using seabed topography 3D model and fault structure on South Central Vietnam’s continental shelf. On the 3D model, landslide evidences occur as narrow and straight steps along continental slope at the depths of 700 - 800 m, 1.200 - 1.300 m and 1.500 - 1.700 m; some landside blocks occur as different dome forms on the middle slope and slope foot. The landslide evidences are also identified on the perpendicular seismic profile  to slope surface and it is especially clear in the new-multibeam data of marine survey in 2013 of national  project KC09.11/11-15. Besides, the results of analyzing structural map of fault and reflected seismic profiles also show that, circular failure modes can occur along the continental slope in study. The boundary of failure blocks can be fault on the crest of slope and  unconformable surfaces. The different analytical results from the fault structure map in Quaternary also show that it is hard for plane failure mode on the fault surfaces to occur in this area, because the  dip angle of fault is always higher than slope angle. However, the occurrence of perpendicular faults to slope surface can break slope surface and increasingly cause submarine landslide in this area.

Keywords


3D model, continental slope, lanslide evidences, submarine landslide, circular failure.

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References


Greene, H. G., Murai, L. Y., Watts, P., Maher, N. A., Fisher, M. A., Paull, C. E., and Eichhubl, P., 2006. Submarine landslides in the Santa Barbara Channel as potential tsunami sources. Natural Hazards and Earth System Science, 6(1): 63-88.

Lopez-Venegas, A. M., ten Brink, U. S., and Geist, E. L., 2008. Submarine landslide as the source for the October 11, 1918 Mona Passage tsunami: Observations and modeling. Marine Geology, 254(1): 35-46.

Tappin, D. R., Watts, P., McMurtry, G. M., Lafoy, Y., and Matsumoto, T., 2001. The Sissano, Papua New Guinea tsunami of July 1998-offshore evidence on the source mechanism. Marine Geology, 175(1): 1-23.

Ten Brink, U. S., Lee, H. J., Geist, E. L., and Twichell, D., 2009. Assessment of tsunami hazard to the US East Coast using relationships between submarine landslides and earthquakes. Marine Geology, 264(1): 65-73.

Mercado, A., and McCann, W., 1998. Numerical simulation of the 1918 Puerto Rico tsunami. Natural Hazards, 18(1): 57-76.

Tinti, S. (Ed.), 1993. Tsunamis in the World (Vol. 1). Springer. 236 p.

Locat, J., Lee, H., ten Brink, U. S., Twichell, D., Geist, E., and Sansoucy, M., 2009. Geomorphology, stability and mobility of the Currituck slide. Marine Geology, 264(1): 28-40.

Kokusho, T., and Takahashi, T., 2008. Earthquake-induced submarine landslides in view of void redistribution. Proceedings of the 2nd international conference on geotechnical engineering for disaster mitigation and rehabilitation (GEOMAR08), Liu, Deng and Chu (eds.), p. 1-12.




DOI: https://doi.org/10.15625/1859-3097/14/4/5821 Display counter: Abstract : 54 views. PDF : 62 views.

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