从陆内到陆缘:中国东部古近纪断陷盆地的深部背景及沉积特征
FROM INTRACONTINENT TO CONTINENTAL MARGIN: THE DEEP BACKGROUND AND DEPOSITIONAL CHARACTERISTICS OF PALEOGENE RIFTED-BASINS OF EAST CHINA
-
摘要: 太平洋板块、印度板块和欧亚板块的演化对中国东部古近纪沉积盆地的沉降及充填具有控制作用。讨论了我国东部新生代断陷盆地群的深部构造背景,在相对统一的板块构造背景中初步分析了陆缘断陷盆地和陆内断陷盆地的形成演化与周边板块主要构造运动事件的关系,并对这种关系的一致性进行了简要讨论。在此基础上,对不同构造演化阶段内的陆缘和陆内断陷盆地的沉积建造特点和沉降中心迁移规律进行了对比分析,对位于中国东部复杂构造体制内不同位置的陆缘与陆内断陷盆地每个构造演化阶段的沉积响应特征及其一致性和差异性进行了初步研究。将东部陆内和陆缘断陷盆地的沉积建造渐变特征或变异规律与深部构造过程表现进行综合分析,对深入理解我国东部陆相断陷盆地群系的盆间关系,深入认识新生代断陷盆地浅部过程与深部过程之间的耦合具有重要理论意义。Abstract: The geological evolution of the three plates of the Pacific, Indian and Eurasian has significant impact on the subsidence and infilling of Paleogene sedimentary basins in East China. This paper first discusses the deep geological structure of the Cenozoic basin groups in East China, then preliminarily analyses the relationship of the formation and evolution between the continent marginal rift basins and intra-continental rift basins and the main tectonic movement in peripheral plates, and at last discusses the relationship of the two kinds of basins. Based on the above discussions, this paper provides a comparative analysis on the characteristics of sedimentary deposits and the migration of the subsidence centers of the marginal rift basins and intra-continental rift basins. This paper also made a preliminary study of the sedimentary responses, consistency and diversity of the two kinds of basins in different tectonic evolutionary stages from different places of the complicated tectonic system in East China. This study is of theoretical significance for better understanding the relationships among continental rift basins in East China as well as the coupling of shallow and deep processes of Cenozoic fault basins.