中文摘要:著名招掖金矿带中金矿床的形成与本区玲珑、滦家河和郭家岭花岗岩有着密不可分的成因联系。根据这些花岗岩的地质和岩石特征，以及主要元素、微量元素、稀土元素的演化特点和黑云母成分分析，认为它们均为地壳深部部分熔融形成的花岗岩。玲珑花岗岩和滦家河花岗岩是同一岩浆源经分异作用形成的不同岩体，郭家岭花岗岩则为晚期侵入岩体。总体为燕山早期同一构造岩浆演化旋回形成的复式岩体。金的成矿作用与郭家岭花岗岩有关。
中文关键词:金矿床 花岗岩的地球化学演化 花岗岩的成因 成矿作用 山东招掖
Abstract:The Zhaoyuan-Yexian area in northwestern part of east Shahgdong is an important gold-producing base and constitutes the well-known Zhao-Ye gold ore belt in which the gold deposits have close genetic relationship with the evolution of Linglong, Luanjiahe and Guojialing granites of this area. The Linglong rock body is a medium-grained gneissic granite body which shows intruding along bedding or cross-cutting contact with old strata of Jiaodong Group and thus contains old strata enclaves of different shapes and sizes whose contents obviously increase at the marginal facies of the rock body. The typical mineral assemblage of the granite is feldspar-quartz-biotite-ilmenite-monazite. Compared with other granites in China or the whole world, it has higher values of Dl, SiO2,Q, AR and lower values of Fe, Mg and K2O/Na2O ratio, with A12O3/(K2O+Na2O+CaO)ratio varying in the range of 1.00-1.10; as for trace elements, it is characterized by higher Ba, Sr contents and Ba/Sr ratio, lower Rb/Sr ratio and∑REE, higher ∑LREE/∑HREE and La/Y ratios as well as slight Eu anomalies. Biotite contains high iron and low magnesium. Calculation shows that the rock-forming pressure is almost the same as the magma-forming pressure(some 0.4 GPa), rock-forming temperature is low(600-685℃), and water fugacity is high(0.22 GPa). Therefore, it is comparable with S type grahires in overall characteristics, thus belonging to contemporaneous granite. The Luanjiahe rock body is a medium-coarse-grained granite body with typical mineral assemblage being feldspar-quartz-biotite-muscovite-monazite-corundum. It obviously shows the same differentiatioⅡand evolution features as the Linglong granite in such aspects as major elements, trace elements and genetic minerals, implying that it is a late differentiation product of the Linglong granite. The Guojialing rock body is a porphyritic granodiorite body characterized by the existence of K-feldspar phenocrysts with different sizes. The rock body also contains a few old strata enclaves and some enclaves of hypogene fine-grained diorite. Its rock-forming age is younger than that of Linglong and Luanjiahe granites, and its typical mineral assemblage is feldspar-quartz-biotite-amphibole-magnetite. Petrochemically, it is rich in Mg, Fe and poor in Q, DI，with A12O3/(K2O+Na2O+CaO)ratio varying in the range of 0.78—0.98. The Guojialing granite and Linglong granite have different genetic characteristics but inherent material connections in the aspects of major elements, trace elements and genetic minerals. The REE pattern of the Guojialing granite is similar to that of the Linglong granite except that the former has higher∑REE. Biotite is relatively rich in Mg. The calculated rock solidification pressure is 0.23 GPa and magma-forming pressure is 1 GPa, indicating that the rock is somewhat of Ⅰ-type granite. From the above discussion, the authors hold that the three different types of granites in this area were all formed by partial melting of the crust. The Linglong and the Luanjiahe granites are different rock bodies formed as a resuit of differentiation of the same magma source at the early stage of evolution. belonging to autochthonous or basically autochthonous type granites with hypabyssal origin and shallow emplacement.The Guojialing granite is a deep source and shallow-emplaced rock body formed by further melting of crust with the mixing of some deep source substances. On the whole, it is a complex rock body produced in the same tectonomagomatic evolution cycle of Early Yanshanian period. The gold deposits are distributed along the endo-and exo-contect zone of the Guojialing granite and were formed later than the granite body. The Guojialing granite is of deep-source shallow-emplacedⅠtype, relatively rich in gold and some other ore-forming trace elements. It is believed that the Guojialing granite is the direct parent rock for gold and the gold deposits are of post-magmatic hydrothermal origin.
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引用文本：
田农，戚长谋，吕以发.1989.山东招掖金矿带花岗岩成因及与金矿床的关系[J].矿床地质,8(2):41~50.1989.The relationship between grainte genesis and gold deposits along the Zhaoyuan-Yexian gold ore belt in shangdong province[J].Mineral Deposits8(2):41~50
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