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中国东南部地槽褶皱区伴随加里东早期和晚期运动,有花岗岩化和岩浆侵入活动。早期形成混合花岗岩和片麻状花岗岩;晚期形成块状花岗岩。前者具最大微斜长石——更、中长石组合;后者为正长石——正长微斜长石——更、中长石组合类型。经研究表明,两期花岗岩具有Na_2O、CaO低,富Al_2O_3、K_2O的岩石化学特性,它们属铝过饱和花岗岩,微量元素贫V、Cr、Ni、Co、Cu、Pb、Zn,而富W、Sn、Be、U、Ga等,什矿物以含铁矿物种类和数量较多,出现铈族稀土元素付矿物而缺钇族稀土元素矿物为特征。上述特征的一致性,表明两期花岗岩具有相同的物质来源。从黑云母富铁,为铁质黑云母,在Fe~(3+)-Fe~(2+)-Mg图上落在Ni-NiO缓冲线之下,说明加里东花岗岩是在氧逸度低的还原环境下形成。稀土元素分配模式,两期岩体也很相似,出现铕的亏损,它明显地不同于华南慢源型的稀土模式。因此加里东花岗岩由地壳沉积物改造而成,属改造型花岗岩成因系列。两期花岗岩虽有相同的物质来源。但有不同的成因方式;地槽沉积物在角闪岩相变质基础上发生部分重熔,低熔组分交代围岩形成加里东早期武功山型混合花岗岩;进一步发展形成深层流化花岗岩——慈竹型和侵入混合花岗岩——石科型。当深部沉积物重熔形成岩浆,它侵位到较上层位形成早期片麻状花岗岩和晚期块状花岗岩。
The geosynclinal fold zone in southeastern China is accompanied by the early and late Caledonian movement with granitization and magmatic intrusion. Early formation of mixed granite and gneissic granite; later formed massive granite. The former has the largest microfacies - more, the combination of feldspar; the latter for the orthoclase - is a long plagioclase - more, the type of combination of feldspar. The study shows that the two phases of granites have the chemical characteristics of Na2O, CaO low, Al2 O3-rich and K2O rich in Al, Fe, Cr, Ni, Co, Cu, Sn, Be, U, Ga and so on. Most of the minerals are characterized by a large number of iron-bearing minerals and rare-earth elements belonging to the cerium group. The consistency of the above characteristics indicates that the two granites have the same material source. From biotite rich iron to ferrous biotite, it falls below the Ni-NiO buffer line on the Fe ~ (3 +) - Fe ~ (2 +) - Mg diagram, indicating that the Caledonian granite is under the condition of low oxygen fugacity The formation of the reduction environment. Rare earth element distribution model, two rock mass is also very similar to the loss of europium, which is obviously different from the South China mode of rare earth rare earth. Therefore, the Caledonian granite was reconstructed from crustal sediments and is a series of generative granite genesis. Although two granites have the same material source. But there are different ways of genesis. The geosyncline sediments partially remelted on the basis of amphibolite facies metamorphism, and the low-melting components account for the surrounding rocks to form the early Wugongshan-type mixed granites in Caledonian. Further development of deep-fluidized granite- Beizhu type and intrusive mixed granite - Shi Ke type. When the deep sediments remelted to form magma, it invaded the upper strata to form early gneissic granite and later massive granite.