摘要
南海北缘新生代沉积盆地是全面揭示南海北缘形成演化及与邻区大地构造单元相互作用的重要窗口。通过对盆地沉积构造特征分析,南海北缘新生代裂陷过程显示出明显的多幕性和旋转性的特点。在从北向南逐渐迁移的趋势下,东、西段裂陷过程也具有一定的差异,西部裂陷活动及海侵时间明显早于东部,裂陷中心由西向东呈雁列式扩展。晚白垩世-早始新世裂陷活动应是东亚陆缘中生代构造岩浆演化的延续,始新世中、晚期太平洋板块俯冲方向改变导致裂陷中心南移,印度—欧亚板块碰撞效应是南海中央海盆扩张方向顺时针旋转的主要原因。
Mesozoic basins in the north margin of the South China Sea were developed as a result of the opening of the South China Sea and influenced by the interaction between Eurasian Plate, Pacific Plate and India-Australian Plate during Cenozoic. It is a very important area to study the relationship between the collision of plates and the opening of the South China Sea.Based on the researches of the subsidence, infilling sequence, discordance of sequence interface of the basin and the structural evolution stage, it can be deduced that the rifting process of the north margin of the South China Sea comprised several rifting phases from north to south. The rifting process of the East Asian continent in Meso-Cenozoic with active rifting characteristics was controlled by the thermal-magmatism. The interaction between plates influenced the evolution of basins remarkably and strike-slip was another feature of the basins. The left lateral strike-slip caused by the subduction of the Pacific Plate under the East Asian Plate in middle Jurassic resulted in the late Mesozoic intensive thermal-magmatism and uplift. After intensive thermal-magmatism, NW-SE trend extension occurred in the East Asian continent during late Cretaceous and rifting basins were developed along NE direction faults. During middle-late Eocene, the subduction direction of the Pacific Plate changed from NNW to NWW trend, which caused the Southwest and Northwest Basins of the South China Sea to open. In early Oligocene, influenced by the collision of India-Asian Plate, the SN trend extension occurred and the Central Basin of the South China Sea opened. In middle Miocene, the extension of the South China Sea ceased due to the converging of the Australian Plate and the arc-continental collision in the Taiwan Region and Pliocene rift was related to the collision.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2005年第2期53-61,共9页
Marine Geology & Quaternary Geology
基金
国家自然科学基金项目(40306010
40376012)
中科院知识创新工程重要方向性项目(KZCX2SW117)
中国科学院广州地球化学研究所与南海海洋研究所边缘海地质重点实验室基金(BYH03A06)
