As a thick residual deposition depression of the Mesozoic strata, the Chaoshan Depression is an important area for oil and gas exploration in the South China Sea (SCS). A lot of multiple-channel seismic (MCS) reflection studies have been conducted in this area, as well as refraction and ocean bottom seismometer (OBS) surveys, but joint P-wave and S-wave studies have not yet been done. Applying the joint exploration of P-wave and S-wave, the complex subsurface crustal structure can be obtained, which is helpful for oil and gas exploration. Based on the P-wave velocity structure of the Mesozoic sediments in the Chaoshan Depression of the profile OBS2006-3, we carried ray tracing and travel-time simulation of converted S-wave. The results reveal that the Mesozoic sediment in the Chaoshan Depression is remarkably thick with the maximum of 8 km, and the P-wave velocity increases downward from 4.4 km·s–1 at the top to 5.3 km·s–1 at the bottom. Accordingly, the S-wave velocity and Poisson’s ratio are 2.6?3.0km·s–1 and 0.24?0.26, respectively, which may imply the composition of Mesozoic strata are sandstone, mudstone and volcanic rocks. According to the geophysical characteristics and previous research in the Chaoshan Depression, this paper analyzes the exploration potential in the Chaoshan Depression.
WEI Xiao-Dong
,
DIAO Meng-Hui
,
RUAN Ai-Guo
,
QIU Hua-Lin
,
XIONG Hou
,
ZHANG Jia-Zheng
. Joint P-wave and S-wave velocity structure of the Mesozoic sediments in the Chaoshan Depression[J]. Journal of Tropical Oceanography, 2012
, 31(3)
: 58
-64
.
DOI: 10.11978/j.issn.1009-5470.2012.03.008
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