摘要
南黄海为一叠置于下扬子地块变质基底之上的中、古生代海相与中、新生代陆相多旋回叠合盆地,经历了长期的构造演化及多期次构造改造。有关南黄海多期次盆地地层格架及分布特征、构造变形及动力机制、盆地性质及成因机制等问题,仍存在诸多争论。本文在总结前人研究的基础上,利用近几年最新获得的地质、地球物理数据,对南黄海有关地层与构造相关的主要问题进行了探讨。地球物理及综合研究表明:南黄海北部燕山晚期以来陆相断陷盆地之下并不存在印支—早燕山期的前陆盆地;朝鲜半岛西缘断裂带是存在的,扬子地块与华北地块汇聚碰撞过程中存在壳内多层次的互相楔入构造;南黄海海相中、古生界广泛分布,往东抬升剥蚀,可能主要残留下古生界,中部隆起残留有完整的下三叠统—震旦系。
The South Yellow Sea basin is a multi-cycle basin with a sandwich-type construction on the pre-Sinian metamorphic basement of the lower Yangtze platform.The geologic evolution of the basin can be divided into three stages:the Sinian-Early Triassic marine basin,the Cretaceous-Paleogene graben fault basin and the Neogene-Quaternary depression basin stages.There are still a lot of debates on the stratigraphic framework and distribution characteristics of multistage basins,basin deformation and dynamics mechanism,basin property and genetic mechanism at present.In this paper,some problems about strata and tectonics in South Yellow Sea are discussed based on geological-geophysical data obtained in recent years,combined with the previous research.The comprehensive research shows that:There is no Indo-Early Yanshanian foreland basin under the fault depression basin since Late Yanshanian in the northern basin of South Yellow Sea.There is indeed a fault zone in the western edge of the Korean Peninsula.In the collision between the Yangtze block and the North China block,there were many multi-layer interwedging structures formed in the crust.The Mesozoic-Paleozoic marine strata are widely distributed in the South Yellow Sea and denuded eastward,and maybe only the lower Paleozoic remains.The whole Lower Triassic-Sinian strata remain in the Central Uplift.