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根据天山地区(4244°N,8189°E)1∶20万化探采集的900余个岩石样品的分析结果,基于全样本统计和迭代剔除方法,得到新疆天山地区表壳(出露地壳)的39种元素丰度值;对其中的SiO2、TiO2、Al2O3、TFe2O3、MgO、MnO、CaO、Na2O、K2O、P2O510种常量元素,按氧化物之和为100%进行归算。与全球大陆上地壳元素丰度值相比,天山地区表壳元素丰度富集SiO2、MnO和Ag、As、Bi、Sb元素,明显亏损CaO和Be、Co、Cr、Ni、Mo、Sn、V、W等元素。从元素比值来看,该区表壳的Ba/La、K/La、K/Th、Nb/La、Th/La、Y/La值与全球大陆上地壳相应元素值相当;而K/Na、La/As、La/Sb值明显低于全球大陆上地壳。该区表壳化学成分相当于花岗闪长岩,同时表现出相对富钠和As、Sb元素的特征;这一地球化学特征与区内出露的表壳岩石主要是加里东期和海西期岛弧造山作用的产物有关,相对富钠的成分特征与岛弧岩浆活动中的Adakite质岩浆作用有关。
Based on the analysis results of more than 900 rock samples collected by the 1: 200,000 geochemical exploration in the Tianshan Mountains (4244 ° N, 8189 ° E), the case of the Tianshan area in Xinjiang (exposed crust) was obtained based on the whole sample statistics and the iterative culling method 39 kinds of elemental abundance values; for which the 10 kinds of elements such as SiO2, TiO2, Al2O3, TFe2O3, MgO, MnO, CaO, Na2O, K2O and P2O5 are all reduced by 100% of oxides. Compared with the crustal elemental abundance values on the global continent, the elemental abundances of SiO2, MnO and Ag, As, Bi and Sb in the Tianshan area are obviously enriched in Ca and Be, Co, Cr, Ni, Mo, Sn, V, W and other elements. In terms of element ratio, the Ba / La, K / La, K / Th, Nb / La, Th / La and Y / La values of this area are similar to those of the corresponding crustal elements on the global continent. La / As and La / Sb values are significantly lower than those of the upper crust on the earth’s continent. The chemical composition of this area is equivalent to the granodiorite chemical composition, and at the same time shows relatively rich in sodium and As, Sb elements; this geochemical characteristics and the exposed area are mainly Caledonian and Hercynian Late Cretaceous orogenic arc, the compositional characteristics of the relatively sodium-rich are related to the magmatic activity of Adakite in the magmatic activity of the island arc.