摘要
南泥湖特大型钼矿床成因类型属矽卡岩-斑岩型钼矿床。其成矿母岩与东秦岭-大别山钼成矿带25个矿床成矿母岩大同小异:(1)分布于大区域巨大花岗岩基外接触带10km范围内;(2)分布于深大断裂与区域断裂的交汇部位;(3)产状为微型岩株,为孤立的复式岩体,出露面积0.12km^2,上小下大,深部隐伏岩体面积大于1km^2;(4)岩石具似斑状结构,斑晶中钾长石为高温变种,石英为13型,斜长石牌号An=7~20,以更长石为主;(5)为强酸性岩石,里特曼指数2.58,属三高一低,即高酸、高钾、高碱,低镁钙的正常太平洋型钙碱性系列的超浅成侵入岩,岩体定位深度〈3km;(6)成矿母岩微量元素主成矿元素Mo〉15mg/kg易成矿,但大部分样品Mo〉50mg/kg,个别样品Mo〉300mg/kg;(7)成岩成矿时代142Ma,属早中侏罗世,燕山早、中期,为最佳成矿时代。
The type of Nannihu oversize molybdenum deposit mother rock is almost the same with 25 deposits in east Qinling belongs to skam -porphyry type, which ore-forming - dabie mountain oreforming belt. 1 ) All distribute in range of 10 kilometers of regional granite litherockg outside contact zone. 2)All distribute in the cross place of regional deepgreat fracture and regional fractures. 3 ) the occurrence is minitype stock, solitary duplex rock mass, emergence area 0.12kmz, up small and bottom big. the rock body under the surface is more than lkm2 ;4)The rock has porphyritic structure,in the porphyritic crystal,the potash feldspar belong to high tempreture, the quartz is j3type, the plagioclase An = 7 - 20, mainly is feldspathaid ;5 ) AU is strong acidic rock, Riteman index 2.58, belong to three high one low, namely high acid, high potassium, high alkali, low magnesium calcium which is super epigenetic invasion rock of normal Pacific Ocean alkaline calcium series ,the deepth of rock body 〈 3 km;6 )The main ore forming element Mo in the oreforming mother rock 〉 15 mg/kg, which easily form ore body, and most part Mo 〉 50mg/kg, individual sample Mo 〉300 mg/kg;7)The time of forming rock and ore is 142 million years,belongs to early middle Jurassic ,early middle time of Yanshan ,which is best time of ore formation.
出处
《中国钼业》
2006年第3期13-17,23,共6页
China Molybdenum Industry
关键词
特大型
钼矿床
成矿母岩
地质特征
oversize type
molybdenum mineral deposit
oreforming mother rock
geology character