DING Yalong, XIE Hong, ZHOU Zhongrong, BI Chenshi

（Institute of Resource and Environment,Guizhou University,Guiyang 550003,China）

 

Abstarct: This paper studies characteristics of elements and evolution of sedimentary environment of the phosphorites from the Late Sinian of Languan area in Weng’an County, Guizhou Province, China. Results show that higher ratios of Ca/Ca+Fe and the growth circumstances of laminar structures reveal that the sedimentary environment is a hyper saline water environment; on the other hand, the Sr/Ba ratios illustrate that the ancient seawater salinity experienced several times of changes. The total value of trace elements, the value of Sr and the ratios of 1000×(Sr/Ca) reflect that the water depth of the sedimentary period in Languan area is shallower and also experiences frequently changes. The existing forms of Fe, the ratios of V/Cr and the value of Ceanom indicate that the sedimentary environment for phosphorites is oxidization. The ratios of Al/Ti and Mg/Ca show that there is more rainfall during the sedimentary period with moist climate.

 

Key words: sedimentary environment; characteristics; element; Guizhou; Wengan; Languan; phosphorite

 

EARTH AND ENVIRONMENT Vol. 43, No.4, Tot No.306, 2015, Page 432-440