从旋回层序的特征论地层记录的两种相变面及两种穿时性

地层记录具四大特性 :“复杂性、非渐变性、不完整性、旋回性”。旋回性地层记录的研究 ,即“不同级别旋回层序及其有序叠加形式”的研究是从复杂而不完整的地层记录中寻找更多的规律性的有效途径之一。异成因旋回层序的两大特征——“空间上相序的有序性及时间上环境变化的同步性”,说明了地层记录中的两种相变面——“静态相变面及动态相变面”以及与之相关的两种穿时性——“相变面穿时及间断面穿时”的普遍性 ,这是地层记录的复杂性的又一重要体现。两种相变面及两种穿时性 ,是地层堆积作用过程中沉积环境的空间相变及时间相变共同作用的结果 ,它们是正确建立时代—岩石格架 ,研究事件对岩石形成影响的基本要素

ON TWO KINDS OF FACIES-CHANGE SURFACE AND TWO KINDS OF DIACHRONONISM IN STRATIGRAPHICAL RECORDS ACCORDING TO THE NATURES OF CYCLIC-SEQUENCES

The four particularities of the stratigraphical records—complexity, non gradual change, non integrity and cyclicity—show that the study of cyclicity is the key for getting more regularity from complex and non integrated stratigraphical records. Two natures of cyclic sequence—the regularity of lithofacies succession in space and the simultanity of environmental change in time—indicate that there are two kinds of facies change surfaces that are dynamic facies change surface and static one, so two kinds of diachrononism—the diachrononism of facies change and the diachrononism of punctuate surface in stratigraphical records—are formed. Two kinds of diachrononism are genetically related to two kinds of facies change surface, facies change diachrononism is genetically related to the static facies change surface, and the diachrononism of punctuated surface is genetically related to the dynamic facies change surface. Two kinds of facies change surface and two kinds of diachrononism in stratigraphical record reflect the complexity of stratigraphical records. The study and discernment of two kinds of facies change surface and two kinds of diachrononism are key for constructing the stratigraphical framwork of time lithounits, and are very important in the study of the systematic change patterns of sediments as well as the influence of various sedimentational processes and the effects of the events on rock formation.