Rare Earths of Two Types Granites in Sawuer Region, Xinjiang

The geochemical characteristics of rare earth elements of A type and Ⅰ type granites were studied in the Sawuer region, Xinjiang. The characteristics of two types granites are different obviously,because the A type and Ⅰ type granites formed at different stage of the post-collisional period. The Sentasi intrusion and Wokensala intrusion are the Ⅰ type granites formed at the late of post-collisional period, and there is extrusion translating to extension stress. The characteristics of rare earth elements show that the fractional crystallization of the Ⅰ type granites is indistinct, and the sources of the Ⅰ type granites come from the mantle. The Kuoyitasi intrusion and Qiaqihai intrusion are the A type granites formed at the end of post-collisional period, and there is extension stress. The characteristics of rare earth elements show that the fractional crystallization of the A type granites is distinct. The sources of the A type granites come from the mantle but interfused by the crust.     

Mechanism of Formation of Premian Volcanic Rocks in Sawu＇er Region, Xinjiang, China： Constraints from Rare Earth Elements

A large quantity of Premian volcanic rocks formed in Sawu＇er region of Xinjiang, China. Based on the analysis of the rare earth elements＇ （REEs） geochemical characteristics of the volcanic rocks, the correlativity of REE and major elements, and diagrams of covariant relation of REE, combined with the research results of the regional geological setting, petrology, and petrochemistry characteristics, it is inferred that the mechanism of the formation of Premian basic and intermediate volcanic rocks is mainly attributed to equilibrium partial melting, and the magmatic fractional crystallization is not significant, whereas the rock-forming processes of medium-acidic volcanic rocks is influenced by both partial melting and fractional crystallization. The REE geochemical research provided important evidence for the mechanism of magmatism of the Premian post-collision stage and the geodynamical evolution process.     

Mechanism of Formation of Premian Volcanic Rocks in Sawu′er Region, Xinjiang, China: Constraints from Rare Earth Elements

Sawu′er region is located in Ji munai County ofAltai regionin Xinjiang Province ,China ,whichis sit-uatedin the northern margin of the Kazakhstan-Jung-gar plate[1 ~3].The large fault in Sawu′er developedinthe central researchregion ,which shapedthe concavelandformin geomorphology withlong and narrowgullysand yakou etc .The western part of the fault developedsecondary faults . The intrusive rocks in the researchregion have developed with an outcrop area of about257 km2.The various types o…     

基于Hazen概率曲线确定铜陵土壤As元素含量

选取已知土壤背景含量的铜陵矿区，基于Hazen概率曲线，探讨了土壤污染重金属元素飚背景含量与污染叠加含量的区分方法。得到As元素的背景含量为12.3μg／g，与该区已知的土壤怂元素背景含量（12．44μg／g）一致。还得到了As元素污染叠加含量与背景含量的界线点20．3μg／g，与据此含量数值计算得出的地积累污染指数的含义相符合。基于Hazen概率曲线区分铜陵矿区土壤触元素背景含量与污染叠加含量的方法是有效的，有必要将该方法推广到土壤中其它重金属污染元素、其它地区作进一步研究。