Back to Search Start Over

Stability of submarine slopes in the northern South China Sea: a numerical approach

Authors :
Liang Zhang
Xiwu Luan
Source :
Chinese Journal of Oceanology and Limnology. 31:146-158
Publication Year :
2013
Publisher :
Springer Science and Business Media LLC, 2013.

Abstract

Submarine landslides occur frequently on most continental margins. They are effective mechanisms of sediment transfer but also a geological hazard to seafloor installations. In this paper, submarine slope stability is evaluated using a 2D limit equilibrium method. Considerations of slope, sediment, and triggering force on the factor of safety (FOS) were calculated in drained and undrained (I broken vertical bar=0) cases. Results show that submarine slopes are stable when the slope is 13A degrees with earthquake peak ground acceleration (PGA) of 0.5 g; whereas with a weak layer, a PGA of 0.2 g could trigger instability at slopes > 10A degrees, and > 3A degrees for PGA of 0.5 g. The northern slope of the South China Sea is geomorphologically stable under static conditions. However, because of the possibility of high PGA at the eastern margin of the South China Sea, submarine slides are likely on the Taiwan Bank slope and eastern part of the Dongsha slope. Therefore, submarine slides recognized in seismic profiles on the Taiwan Bank slope would be triggered by an earthquake, the most important factor for triggering submarine slides on the northern slope of the South China Sea. Considering the distribution of PGA, we consider the northern slope of the South China Sea to be stable, excluding the Taiwan Bank slope, which is tectonically active.

Details

ISSN :
19935005 and 02544059
Volume :
31
Database :
OpenAIRE
Journal :
Chinese Journal of Oceanology and Limnology
Accession number :
edsair.doi...........f83d483871f6ad1941082462251f6a73
Full Text :
https://doi.org/10.1007/s00343-013-2060-z