The composition of terrigenous clastic rock is the comprehensive reflection of the whole process from the weathering denudation to the sedimentary rock. Because the trace elements are not active

the influence of external force in diagenesis

metamorphism

weathering

transportation and deposition is small. By studying the trace elements content and distribution characteristics in sedimentary rock

especially the ratio of some related elements can be concluded that the sedimentary environment and inversion of geological conditions at that time. Combined with previous studies of using of La、Th、Sc、Zr、Ti、Co and Ni and other trace elements can be used to discriminant information of prowenance source rock properties

sedimentary environment and tectonic background. The indicating significance of ω（Sr）/ ω（Ba）

ω（Sr）/ ω（Ca）can be inductived to study the ancient climate change. A variety of sedimentary tectonic setting discrimination diagram and related parameters of La-Th

La-Th-Sc

Th-Co（Sc）-Zr can be summarized and discriminated the research significance in clastic sedimentary environment and sedimentary tectonic background. And the indicating significance of clastic sediment source in the changing trend of trace element ratio of ω（La）/ω（Sc） and ω（Co）/ω（Th） can be studied.