HR: 1340h
AN: OS53A-0974    [Abstracts]
TI: Insights from new bathymetric, gravimetric and magnetic data of the continental margin of the northern South China Sea
AU: Chen, K
EM: kuan620@gmail.com
AF: National Central University, 300, Chung-Da Road, Chung-Li, 32001, Taiwan
AU: * Hsu, S
EM: hsu@ncu.edu.tw
AF: National Central University, 300, Chung-Da Road, Chung-Li, 32001, Taiwan
AU: Huang, C
EM: iamdavid45@gmail.com
AU: Lee, C
EM: leecs@ntou.edu.tw
AF: National Taiwan Ocean University, 2, Peining road, Keelung, 20224, Taiwan
AU: Huang, Y
EM: janushuang711@gmail.com
AU: Tsai, C
EM: s0642002@gmail.com
AU: Doo, W
EM: wenbindoo@gmail.com
AU: Ku, C
EM: ChiaYen.KU@gmail.com
AU: Yeh, Y
EM: yichingyeh@gmail.com
AB: The opening of the South China Sea Basin is suggested to be started from Late Eocene (ca. 37 Ma). The sea floor spreading began from the northern South China Sea. After the spreading, the oceanic crust was in fact intruded by post-spreading volcanism. The obvious evidence is that sea mounts are distributed in the northern South China Sea. To better understand the transition from continental crust to oceanic crust, we have conducted a marine geophysical survey in the continental margin of the northern South China Sea by using R/V Marion Dufresnes. New bathymetric data show that the margin in the southwest is relatively steeper than in the northeast. Several canyons have cut through the continental slope. In contrast, the slope is quite diffusive in the northern portion. However, the sea mounts are concentrated near the Tung-Sha (Pratas) island. The presence of the sea mounts in this area suggests that the post-spreading volcanism had occurred in the continental-ocean transition zone. Is the continental margin of the northern South China Sea an active margin or a passive margin? It is still controversial. The mechanism and distribution of the volcanism in the northern South China Sea need to be further explored. That will improve our understanding about the formation or break-up of the South China Sea continental margin.
DE: 3000 MARINE GEOLOGY AND GEOPHYSICS
DE: 3040 Plate tectonics (8150, 8155, 8157, 8158)
DE: 3045 Seafloor morphology, geology, and geophysics
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting