Oligocene-Miocene carbonates in the Reed Bank area, South China Sea, and their tectono-sedimentary evolution
Oligocene-Miocene carbonates in the Reed Bank area, South China Sea, and their tectono-sedimentary evolution
复制标题
南海芦苇滩地区渐新统-中新统碳酸盐岩及其构造沉积演化
DOI：
10.1007/s11001-014-9237-5
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发表时间：
2015
影响因子：
1.4
通讯作者：
Fang Yinxia
中科院分区：
文献类型：
--
作者：
Ding Weiwei;Li Jiabiao;Dong Congzhi;Fang Yinxia
We have analyzed two recently acquired multi-channel seismic profiles across the Reed Bank area, South China Sea. A detailed seismic interpretation coupled with drilling data has proved the occurrence of a wide carbonate platform, developed between the Late Oligocene and the Early Miocene (32–20 Ma). The top of these carbonates is an important regional unconformity, corresponding to a strong and continuous seismic reflector. An age of about 20 Ma is inferred for this reflector, acting as a regional unconformity marking the cessation of seafloor spreading with an erosional/non-depositional hiatus, spanning 3 or 4 m.y. The time interval during which the carbonate platforms formed is concurrent with the opening of the South China Sea. The reconstruction of the tectonic subsidence in this area has shown a decrease in rate of subsidence during the drifting stage (32–17 Ma), indicating that the whole Reed Bank area was in a tectonically stable and shallow water environment for more than 10 m.y., favoring the development of shallow water carbonates. With a sharply increased subsidence rate after the end of spreading (17 Ma) and a continuously increased sea level, the carbonate platforms were drowned and died, except some structural highs with reef buildups, where the carbonate sedimentation continued to Middle Miocene. We suggest that delayed tectonic subsidence in Reed Bank area might have been related to a secondary mantle convection under the rift lasting more than about 10 m.y.
