南鄂尔多斯盆地的成因地层格架及沉积演化过程

采用过程沉积学分析和沉积构成研究相结合的方法,在古代沉积岩系中划分沉积总体(夏文臣等,1989)和建立沉积模式是宏观沉积学研究的基本思路。如果在此基础上,以沉积总体为基本构成单位,研究整个盆地的充填样式和成因地层格架,无疑会对盆地的演化历史和形成机制有更深入的认识,因而也就可以更有效地把握沉积矿产或层控矿产的分布规律及成矿过程。现以南鄂尔多斯盆地为例,对中国东部早中生代大型内陆坳陷盆地的充填样式成因地层格架和演化过程给予概要的讨论。

GENETIC STRATIGRAPHIC FRAMEWORK AND SEDIMENTARY EVOLUTION OF SOUTHERN ORDOS BASIN

Four types of basin-fill patterns and the whole genetic stratigraphic framework of a intracontinental basin are established according to internal and external depositional architectures of every kind of the depositional packages in the Ordos basin. The basin-fill patterns include alluvial plain/interchannel lake pattern, fan-delta/lake pattern, alluvial plain/lacustrine delta/lake pattern and lacustrine delta/lacustrine clastic shoreline/deep lake pattern. Furthermore, on the basis of the study of different stratigraphic interfaces, the evolution of the basin may be divided into two tectono-depositional episodes, each of which, in turn, may be subdivided into several depositional episodes. The features described here are thought to be characteristic of multicyclicity of the basin evolution.