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温泉钼矿床是一个与三叠纪花岗岩有关的斑岩型钼矿床.温泉岩体地球化学特征上富集LILE和LREE,贫化HFSE,较岛弧火山岩有明显高的碱(K2O+Na2O)和Sr,Ba含量,与高钾钙碱性系列的后碰撞花岗岩相似.温泉岩体的常量元素、微量元素、稀土元素及年代学资料显示,它们是在陆-陆挤压碰撞向伸展转化地球动力学条件下,由富集的岩石圈地幔发生部分熔融产生的基性岩浆和其所诱发的加厚下地壳部分熔融形成的酸性岩浆混合的产物.5件辉钼矿的Re-Os同位素定年结果显示,辉钼矿Re-Os模式年龄在(212.7±2.6)～(215.1±2.6)Ma之间,其加权平均值(214.1±1.1)Ma,由ISOPLOT程序获得的等时线年龄为(214.4±7.1)Ma.该年龄与前人报道的温泉岩体的K-Ar年龄(223～226Ma)和SHRIMPU-Pb锆石年龄((223±7)Ma)在误差范围内相近但偏晚,反映Mo矿化主要发生在岩浆侵入-成岩的晚期阶段,成岩成矿发生于华北与华南板块全面对接后秦岭造山带构造体制由碰撞到后碰撞的转折阶段,并与南秦岭的变质变形、勉-略洋盆闭合及大别-苏鲁超高压岩石板片折返这一统一地质事件相对应.中三叠世华北和华南发生大规模陆-陆碰撞并导致地壳明显增厚或俯冲板片折返,印支晚期构造体制进入由碰撞到碰撞造山后伸展的转折阶段,地幔软流圈物质上涌并底侵于下地壳底部而诱发的下地壳物质的部分熔融形成富Mo的花岗质岩浆,岩浆冷凝分异出的成矿流体使成矿元素Mo富集成矿.秦岭造山带的斑岩钼矿床主要形成于2个时期,即220Ma左右和140Ma左右,这两个成矿作用均发生于从挤压到伸展转变的构造环境,但是它们发生在秦岭造山带不同的构造演化阶段.温泉钼矿床的发现,表明西秦岭三叠纪构造岩浆岩带是秦岭造山带又一重要的Mo矿化有利地带,对西秦岭三叠纪花岗岩的含矿性评价研究应当引起今后重视.
The Wenquan molybdenum deposit is a porphyry molybdenum deposit related to the Triassic granite.The geochemical characteristics of the hotspring are enriched in LILE and LREE, depleted in HFSE, and significantly higher in alkali (K2O + Na2O) and Sr and Ba are similar to the high-K calc-alkaline series of post-collision granites.The data of the elements, trace elements, rare earth elements and geochronology of the hot spring rock mass indicate that they are in the process of continental-continental crush collision to extension transformation geodynamics Under the conditions of learning, the basic magma produced by the partial melting of the enriched lithospheric mantle and the acid magma formed by the partial melting of the thickening lower crust induced by it are the result of the Re-Os isotopic dating of the five molybdenites The results showed that the Re-Os mode of molybdenite was (212.7 ± 2.6) ~ (215.1 ± 2.6) Ma and its weighted average value was (214.1 ± 1.1) Ma. The isochron age obtained by ISOPLOT program was (214.4 ± 7.1) Ma. This age is similar to the K-Ar ages (223 ~ 226 Ma) and SHRIMPU-Pb zircon ages ((223 ± 7) Ma) Mineralization occurs mainly in the late stages of magmatic intrusions and diagenesis. Diagenesis and mineralization occur in the whole of North China and South China After docking, the structural system of Qinling orogenic belt changed from collision to post-collision, and corresponded with the unified geologic event such as metamorphic deformation of South Qinling, Mian-Luan ocean basin closure and reentry of Dabie-Sulu ultra-high pressure rock plate. Large-scale land-continent collisions in North China and South China caused a significant thickening of the crust or subducting slab reefs. Late Indo-China structural system entered the transitional stage of extension from collision to orogeny, and mantle asthenosphere was surging toward the end Partial melting of the lower crustal material induced by intrusion into the bottom of the lower crust forms part of the Mo-rich granitic magma, and the ore-forming fluids that are condensed by the magmatic condensate enrich the ore-forming elemental Mo for mineralization.The porphyry molybdenum deposit in the Qinling orogenic belt is mainly Formed in two periods, about 220Ma and about 140Ma, both of which occurred in the tectonic setting from extrusion to extensional transformation, but occurred in different tectonic evolution stages of the Qinling orogenic belt. , Indicating that the Triassic tectonic magmatic belt in the West Qinling is another important Mo mineralization favorable zone in the Qinling orogenic belt and that the study on the evaluation of the Triassic granite in the West Qinling should lead to the future heavy Visual.