CONTEMPORANEOUS DEFORMED STRUCTURES IN LACUSTRINE SEDIMENTARY ROCKS AND THEIR GEOLOGICAL SIGNIFICANCE
湖相沉积岩中的同生变形构造及其地质意义

This paper takes the contemporaneous deformed structures cccured in lacustrine sedimentary rocks of Sha-3 and Sha-4 Members, Lower Tertiary, Dongpy Depression, at the edge of Bohai bay basir, as an example, to discuss their nomenclature, classification, main types, formation mechanism, and application to the analysis of sedimentary paleoenvironment, paleogeography and paleostructure, This approach supplies with correlation busis for studying contemporaneous deformation structure in terrestrial petroleum-bearing basins. The classification of the contemporanecus deformed structures in lacustrine rocks in this paper is as follows: 1. Deformational structures which were formed dominantly by vertical movement of soft sediments include convolution and its association structures and log ding and its associated structures. 2. Those which were formed dominantly by lateral movement of soft sediments include sliding and its association structures and slumping and its associated structures. 3. Those which resulted from dominantly liquid escape and its associated structures, include upward migration of liquefied sand flow and its associated structures. 4. The 4th type of contemporaneous deformed structures occur in the gypsum-mud sediment.