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民都洛岛、巴拉望岛北部和礼乐滩(西南菲律宾群岛)一起构成了一个陆块,即北巴拉望断块,它位于岛弧-大洋构造背景之内。这些地区的二叠纪到早第三纪岩石反映了这个断块具有与菲律宾群岛其余部分截然不同的地质成因和历史。这些岩石还表明,北巴拉望断块在漂移前一度曾处于同华南陆地相邻的位置上。在中国大陆的沿岸和岸外地区,以及在台湾和北巴拉望断块,识别出了四个明显的晚第三纪以前的区域性不整合。这些不整合的同时性以及不整合沉积单元的岩相关系有力地表明,所有这些地区都具有一部共同的晚第三纪以前的历史。相反,在整个巴拉望地区出现于中中新统顶部的一个重要区域不整合在亚洲陆地却完全缺失。自中生代以来分隔北巴拉望断块和亚洲大陆的南中国海盆地的引张作用,从西到东大体是一致的。然而,有明显的证据表明,这种引张作用是由间隔短暂的大陆地壳减薄阶段和近代海底扩张阶段造成的。根据先前的观察,並利用南中国海最新的扩张磁异常资料,编绘出了一套复原图,它们展示了南中国海从晚三叠世到上新世的演化。这些复原图说明:(1)在体罗纪和白垩纪的大部分时期内,北巴拉望断块位于会聚大陆边缘的背景内;(2)菲律宾岛弧系开始形成于晚白垩世;(3)后来从晚始新世起,该弧系发生了逆时针转动;(4)古新世到中中新世,南中国海张开;(5)早到中中新世,在北巴拉望断块和巴拉望俯冲系之间发生了碰撞。
Mindoro Island, northern Palawan Island and Reed Beach (Southwest Philippines) together form a landmass, the North Palawan block, which is located within the island arc-oceanic tectonic setting. The Permian to Early Tertiary rocks in these areas reflect the distinct geological origin and history of this fault block that is distinct from the rest of the Philippine archipelago. These rocks also indicate that the North Palawan block was once located adjacent to the South China land before drifting. In the coastal and offshore areas of mainland China and the fault blocks in Taiwan and the Northern Palawan, four distinct regional unconformities were identified before the late Tertiary. The homogeneity of these unconformities and the lithofacies of unconformity sedimentary units strongly suggest that all of these regions share a common history of the late Tertiary. On the contrary, an important regional unconformity that appeared on the top of the Central China Epoch in the entire Palawan region was completely missing on the Asian continent. The extension of the North Palawan block and the South China Sea Basin of the Asian continent since the Mesozoic are largely consistent from west to east. However, there is clear evidence that this extension is caused by the short-lived continental crustal thinning and the modern phase of submarine expansion. Based on previous observations, and using the most recent data on the dilatational magnetic anomaly in the South China Sea, a set of reconstructed maps were compiled showing the evolution of the South China Sea from the Late Triassic to the Pliocene. These reconstructed maps illustrate (1) that the Palaeo-Palawan block was within the background of converging continental margins during most of the Tano and Cretaceous periods; (2) the Philippine island arc began to form in the Late Cretaceous; ( 3) Later, from the Late Eocene, the arc system turned anticlockwise; (4) the Paleocene to the Middle Miocene with the opening of the South China Sea; (5) Early Middle Miocene, There was a collision between the pull block and the Palawan subduction system.