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南岭地区中-晚侏罗世含铜铅锌与含钨花岗岩的矿物学和地球化学特征截然不同.含铜铅锌花岗岩主要为准铝质含角闪石的花岗闪长岩,具有较高的CaO/(Na_2O+K_2O)比值、LREE/HREE比值和δEu值,较低的Rb/Sr比值,Ba、Sr、P、Ti轻微亏损,分异演化程度较低.含钨花岗岩为高分异演化的过铝质花岗岩,其CaO/(Na_2O+K_2O)比值、LREE/HREE比值和δEu值较低,Rb/Sr比值较高,Ba、Sr、P、Ti强烈亏损.含铜铅锌花岗岩主要形成于155.2~167.0Ma,峰值为160.6Ma,含钨花岗岩主要形成于151.1~161.8Ma,峰值为155.5Ma,两者存在约5Ma的时差.在湘南铜山岭含铜铅锌和魏家含钨花岗岩系统研究基础上,结合南岭地区中-晚侏罗世含铜铅锌与含钨花岗岩的对比,提出了两类含矿花岗岩的成因模式.古太平洋板块俯冲导致软流圈上涌和玄武质岩浆底侵.底侵玄武质岩浆加热促使下地壳镁铁质角闪岩相基底首先发生部分熔融,形成与铜铅锌矿化有关的花岗闪长质岩浆.随着玄武质岩浆底侵,中-上地壳富白云母变质沉积基底发生部分熔融,形成与钨矿化有关的花岗质岩浆.花岗岩源区成分的差异导致花岗岩成矿专属性不同,源区部分熔融的时间先后导致了含铜铅锌与含钨花岗岩之间存在5Ma左右的时差.
The mid-late Jurassic copper-lead-zinc in the Nanling area is very different from the mineralogical and geochemical characteristics of the tungsten-bearing granite.The copper-bearing Pb-Zn granites are mainly quasi-aluminous amphiboles containing granodiorites, High ratios of CaO / (Na_2O + K_2O), LREE / HREE and δEu, low Rb / Sr ratios, slight loss of Ba, Sr, P and Ti, The different evolved peraluminous granites have lower ratios of CaO / (Na 2 O + K 2 O), LREE / HREE and δEu, higher ratio of Rb / Sr and strong depletion of Ba, Sr, P and Ti. Mainly formed at 155.2 ~ 167.0Ma with a peak value of 160.6Ma. The tungsten-bearing granite mainly formed at 151.1 ~ 161.8Ma with a peak value of 155.5Ma, with a time difference of about 5Ma. Based on the study of granite system and the comparison of the mid-late Jurassic Cu-Pb-Zn and W-containing granites in the Nanling area, two types of ore-bearing granite genesis models are proposed.The subduction of Paleo-Pacific plateau leads to upwelling of asthenosphere and basalts Intrusion of magmatic underplating, basaltic basaltic magma heating causes partial melting of the mafic amphibolite facies in the lower crust to form Copper-lead-zinc mineralization related to the granodiorite magma.With the basaltic magmatic underplating, the mid-upper crust-rich muscovite metamorphic sedimentary basement partially melted to form a tungsten mineralization-related granitic magma granite source The differences in the composition of the granites lead to different ore-forming specialties. The partial melting time of the source zone has led to a time difference of about 5Ma between the copper-bearing lead-zinc and the tungsten-bearing granites.