Abstract: Zircon crystal content and its morphologic parameter features in different lays and trace element marks of tonsteins have been studied in this article. The study is based on the synsedimentary volcanicash derived tonsteins in late-permian coal-bearing formation of eastern Yunnan and western Guizhou. China. Their changing patterns in various lays and in identical lay area have been preliminarily ascertained which have a unique effect upon the precise identification of lays. It has an important and practical value that using this approach to distinguish lay’s position in the area with complicated structure, or in the area with normal lay orders having been suffered severe destruction.