Analysis on the Formational Mechanism of Depositional Cycles

Key words: 
• rhythm /
• depositional cycle /
• tectonic activity /
• climatic fluctuation /
• main control factor /
• depositional response

Abstract: Cyclicity character is one of the most important attributes of depositional strata, and it looks more important in the terrestrial sediments. Rhythmicility or periodicity of the depositional strata is materialized by the transformations of lithological characters in strata ordinally, and it is incarnated by the transformations of ingredient, granularity, color, intensity of the depositional compensation, intensity of oxidationdeoxidation, and the character of biome. Rhythmicility or periodicity of the depositional strata is influenced by the fluctuation of sealevel to a certain extent, but it must be the response of depositional course to the structural activity in extensive significance.