【摘要】：青海昆侖河地區(qū)地處東昆侖造山帶昆南增生雜巖帶內(nèi),區(qū)內(nèi)近年來發(fā)現(xiàn)了以銅金山、二道溝為代表的鎢礦床。本文在野外地質(zhì)調(diào)查的基礎(chǔ)上,結(jié)合巖礦鑒定、流體包裹體分析測試等室內(nèi)研究,分析了區(qū)內(nèi)兩個典型鎢礦床的地質(zhì)特征、流體包裹體特征,厘定了礦床類型,探討了礦床成因以及成礦作用過程。銅金山鎢多金屬礦體產(chǎn)于蝕變大理巖中。礦石中金屬礦物主要為白鎢礦,次為黃銅礦、方鉛礦、輝銅礦、輝銀礦、斑銅礦、黝錫礦等;非金屬礦物主要為石英、透閃石,次為蛇紋石、方解石等。礦石組構(gòu)主要為自形-半自形粒狀結(jié)構(gòu)、交代殘余結(jié)構(gòu),稀疏浸染狀構(gòu)造。成礦與硅化、透閃石化關(guān)系密切。成礦作用可分為:Ⅰ.透閃石-石英-白鎢礦階段、Ⅱ.石英-硫化物-白鎢礦階段和Ⅲ.方解石-滑石階段,其中Ⅰ、Ⅱ階段為主成礦階段。主成礦階段均主要發(fā)育氣液水兩相包裹體,少見CO_2-H_2O包裹體。Ⅰ階段流體包裹體均一溫度為中高溫、中低鹽度,Ⅱ階段為中低溫、中低鹽度。兩個階段的流體均屬H_2O-NaCl-CH_4±CO_2體系。二道溝鎢礦體由含礦石英脈組成,產(chǎn)于千枚巖、板巖中。礦石中金屬礦物主要為白鎢礦,硫化物少見。白鎢礦主要產(chǎn)于石英脈內(nèi)及兩側(cè)圍巖中。礦石組構(gòu)主要為自形-半自形粒狀結(jié)構(gòu)、交代殘余結(jié)構(gòu),浸染狀構(gòu)造。主成礦階段石英和白鎢礦中發(fā)育氣液水兩相包裹體、CO_2-H_2O包裹體,偶見含子礦物三相包裹體、熔融包裹體。成礦流體屬高溫、高-中-低鹽度共存的H_2O-NaCl-CH_4-N2-CO_2體系,具有巖漿熱液特點。成礦過程中發(fā)生過流體不混溶作用。銅金山鎢多金屬礦床為交代巖型鎢礦床,其形成與中高溫含礦流體滲濾交代大理巖有關(guān)。流體中Ca~(2+)濃度增大、pH值升高、溫度下降,導(dǎo)致白鎢礦結(jié)晶沉淀。二道溝鎢礦床為熱液脈型鎢礦床,其形成與高溫含礦熱液充填有關(guān)。成礦過程中流體發(fā)生不混溶作用,使CO_2逸出流體相,pH值升高,導(dǎo)致白鎢礦結(jié)晶沉淀。
[Abstract]:The Kunlun River area in Qinghai is located in the southern Kunnan accretive complex belt of the East Kunlun orogenic belt. In recent years, the tungsten deposits represented by Tongjinshan and Erdaogou have been discovered in the area. On the basis of field geological investigation, combined with laboratory studies such as rock ore identification, fluid inclusion analysis and testing, the geological characteristics and fluid inclusion characteristics of two typical tungsten deposits in the area are analyzed, and the deposit types are determined. The genesis and metallogenic process of the deposit are discussed. The Tongjinshan tungsten polymetallic ore body occurs in altered marble. The main metallic minerals in ore are scheelite, chalcopyrite, galena, chalcopyrite, pyroxene, porphyrite, tetrahedrite and so on, while the non-metallic minerals are mainly quartz, tremolite, serpentine, calcite and so on. The ore fabric mainly consists of the granular structure of automorphism and hemiautomorphism, the metasomatic residual structure and the sparse disseminated structure. Mineralization is closely related to silicification and tremolysis. The mineralization can be divided into: 鈪，

本文編號：2288501