Abstract:

The fundamental factors which control such deposits as source rocks,coal series and evaporites are palaeo-climate and regional structural setting.With regard to regional structural setting,five main problems are discussed. 1.A single faulted basin of dustpan-shape is the fundamental structural element of Cretaceous-Early Tertiary evaporite-and source rock-bearing basins in Eastern China,which are complicated by secondary faults and diapirism of salt (or clay) beds in late stage.2. The single faulted basins are formed by tenssion. 3.The faulted lake basins have undergone several stages:(a) initial stage;(b) stage of development; (c) stage of contraction and (d) final stage. A large amplitude of depression of the lake basins are formed due to multi-tectonic movements,and the non-uniform uplifts of the basement have resulted in the discontinuous sediments and overlap of Tertiary.4. According to the evolutional stage of the faulted basins,the evaporites and source rocks may be divided into two main types. (a) The evaporites associated with source rocks are related to the stage of development of the basins; (b)The evaporites associated with red beds are related to the stage of contraction of the basins.5. The distribution of the evaporites is controlled by the morphology of the faulted basins and terrigenous fragment supplies around.