阳春盆地锡山钨锡矿床钾长花岗岩的矿物学特征及地质意义  

Mineral characteristics of alkali feldspar granites from Xishan W-Sn deposit in Yangchun basin and their geological significance

作　　者：欧阳志侠 刘东宏 汪礼明 梁金龙[2] 汪汝澎 吴晓东 杨胜虎 OUYANG ZhiXia;LIU DongHong;WANG LiMing;LIANG JinLong;Wang RuPeng;WU XiaoDong;and YANG ShengHu(Geological Bureau for Nonferrous Metals of Guangdong Province,Guangzhou 510080,China;Chengdu University of Technology,Chengdu 610059,Sichuan,China)

机构地区：[1]广东省有色金属地质局,广东广州510080 [2]成都理工大学地球科学学院,四川成都610059

出　　处：《矿床地质》2018年第4期868-885,共18页Mineral Deposits

基　　金：国家自然科学基金项目(编号:41702083);中国博士后科学基金项目(编号:2018T110125;2017M610105);中国地质调查局地质调查工作项目(编号:12120114015801;1212011120826)共同资助的成果

摘　　要：锡山钨锡多金属矿是粤西阳春盆地内一个中型石英脉型矿床,成矿岩体岩性为钾长花岗岩,主要矿物组成为钾长石、斜长石、石英、黑云母,副矿物包括锆石、磷灰石、金红石、钛铁矿和铌铁矿等。文章利用电子探针技术对主要矿物的矿物学特征进行了研究,结果表明花岗岩中斜长石为钠长石,钾长石为透长石,黑云母属于铁叶云母。黑云母化学成分显示其w(Ti)介于0.19~0.39,具有低的氧逸度(log f(O2)<Ni-Ni O),指示其有利于钨锡矿床的形成且仍具有较好的找矿潜力。结合已有的区域地质资料,文章认为锡山钨锡多金属矿床是岩石圈伸展背景下的产物。The Xishan W-Sn polymetallic deposit, located in the Yangchun basin of western Guangdong Province, is a medium-sized quartz vein W-Sn deposit. The deposit is temporally and spatially associated with Xishan alkali feldspar granite, which mainly consists of K-feldspar, plagioclase, biotite and quartz. Accessory minerals include zircon, apatite, rutile, ilmenite and niobite. Systematic petrological and mineralogical investigation indicates that the plagioclase is albite, K-feldspar is mainly orthoclase, and biotite is siderophyllite. The Xishan granite has Ti content of 0.19～0.39 and low oxygen fugacity （log f（O2） 〈 Ni-NiO）, which is more conducive to the formation of W-Sn deposits and thus exhibits a higher potential. These results, together with previously presented regional geological relationships, suggest that the formation of the Xishan alkali feldspar granite and other Cretaceous magmatism in the region was related to lithospheric extension.

关 键 词：地球化学 钾长花岗岩 矿物学特征 锡山钨锡矿 阳春盆地 云开地区 

分 类 号：P618.67[天文地球—矿床学] P618.44[天文地球—地质学]