Rifting characteristics of eastern subbasin of South China Sea and its spreading pattern
Rifting characteristics of eastern subbasin of South China Sea and its spreading pattern
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发表时间：
2002
影响因子：
1.4
通讯作者：
Li;Jiabiao;Jin;Xianglong;Gao;Jinyao
中科院分区：
文献类型：
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作者：
Li;Jiabiao;Jin;Xianglong;Gao;Jinyao
通过对南海东部25 000 km全覆盖多波束条带数据的处理和解释，发现东海盆中部（14° <$17 ° N）存在北东向和北西向的陡坎、地垒和地堑等线状地貌特征。通过与反射地震剖面的对比，认为这些北东向线性构造地貌是海底基底构造的代表，并可划分为3个线性构造带。中心带走向为NE 45 ° <$50 °，位于绝灭扩张中心周围;第二带走向为NE 70 ° <$78 °，位于中心带两侧;这三条NE向线性带是在东海盆NW-SE向海底扩张晚期沿着NW向线性断裂形成的，根据形态构造与磁线理异常的对比，分别对应于17.0 ~ 19.0 Ma（5d-5e）、19.0 ~ 21.0 Ma（5e-6a）和21.0 ~ 24.2 Ma（6a-6c）三个扩张幕。
With processing and interpretation of 25 000 km full-coverage multibeam swath data from the eastern South China Sea, it is found that NE-trending and NW-trending linear morphological features such as scarps, horsts and grabens, govern the central part (14°∼17° N) of eastern subbasin. Compared with reflection seismic profiles, these NE-trending linear morpho-structures are considered to be the representation of basement structures on seabed and can be divided into three linear structural zones. The trend of the central zone is NE45°∼50° occurring around extinct spreading center, the trend of the second zone is NE70°∼78° on both sides of the central one and the trend of the third zone is about NE60° just on the north of the second one. These three NE-trending linear zones are formed in late-stage NW- SE-trending seafloor spreading of the eastern subbasin along NW-trending linear faults, and respectively correspond to three spreading episodes: 17.0∼19.0 Ma (5d-5e), 19.0∼21.0 Ma (5e-6a) and 21.0∼24.2 Ma (6a-6c) based on the contrast of morpho-structures to magnetic lineation anomalies.