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东塔尔别克金矿区位于西天山吐拉苏盆地内阿希金矿区南侧,构造上属于伊犁-中天山微板块与准噶尔板块之间的博罗科努早古生代岛弧带西段。东塔尔别克矿区出露有一些安山岩,这些岩石具有典型高镁安山岩特征,如高硅(SiO_2=58.94%～63.85%),具有较高的MgO含量(3.75%～6.59%)和Mg~#(58～69)、高的Cr(94.2×10~(-6)～241×10~(-6))、和Ni (54.5×10~(-6)～126×10~(-6))含量,以及低的FeO~T/MgO比值。除了Sr含量略微偏低(235×10~(-6)～696×10~(-6))之外,这些岩石基本显示了埃达克岩的地球化学特征:高的Al_2O_3(15.39%～16.65%),低Y(9.86×10~(-6)～14.9×10~(-6))含量,以及高的Sr/Y比值(23.8～48.1),无Eu异常,Nb、Ta、Ti亏损等。LA-ICP-MS锆石U-Pb测年结果显示安山岩的年龄为347.2±1.6Ma,为早石炭世。安山岩富集Rb、Th、U等大离子亲石元素,相对亏损Nb、Ta、Ti等高场强元素,轻重稀土元素分馏明显,具有俯冲带岛弧岩浆的特征。东塔尔别克安山岩可能形成于岛弧环境中,并可能由俯冲的晚古生代北天山洋洋壳以及少量上覆沉积物熔融形成,产生的熔体在上升过程中与地幔橄榄岩发生了相互作用.熔体-地幔相互作用对区内金矿的形成具有重要意义。
The East Talbot Gold Mine is located on the southern side of the Ashi gold deposit in the Tulusu Basin of the Western Tianshan and is structurally belonged to the western section of the Early Paleozoic arc belt of the Boluo Kounu between the Ili-Zhongtian Mountain micropan and the Junggar plate. There are some andesite exposed in the East Talbot mining area. These rocks are characterized by typical high-Mg andesite such as high silica (SiO 2 = 58.94% -63.85%), high MgO content (3.75% -6.59%) and Mg ~ (58 to 69), high Cr (94.2 × 10 -6 to 241 × 10 -6), and Ni (54.5 × 10 -6 to 126 × 10 -6) Content, and low FeO ~ T / MgO ratio. In addition to the slightly lower Sr content (235 × 10 -6 -696 × 10 -6), these rocks basically show the geochemical characteristics of Adakite: high Al 2 O 3 (15.39% ~ 16.65 %), Low Y (9.86 × 10 -6 ~ 14.9 × 10 -6), high Sr / Y ratio (23.8 ~ 48.1), no Eu anomaly, Nb, Ta, Ti loss etc. . LA-ICP-MS zircon U-Pb dating results show that the age of andesite is 347.2 ± 1.6Ma, which is Early Carboniferous. Andesite is rich in large ion lithophile elements such as Rb, Th, U and relatively depletes high field strength elements such as Nb, Ta and Ti. The fraction of light and heavy rare earth elements is fractionated and has the characteristics of subducted island arc magma. The East Talbot Andesite may be formed in an arc-arc environment and may be formed by the subduction of the late Paleozoic northern Tianshan oceanic crust and a few overlying sediments. The resulting melt interacts with the mantle peridotite during its ascent. Melt-mantle interaction plays an important role in the formation of gold deposits in the area.