北秦岭蟒岭地区萤石矿地质特征与找矿潜力

蟒岭岩体地处秦岭腹地,横跨豫陕两省,与其相关的矿产资源丰富,大地构造位置位于秦岭复合型大陆造山带之北秦岭构造带。成矿区带隶属北秦岭牧护关—蟒岭燕山期铁铜钼钨铅锌萤石成矿带,共发现萤石矿床(点) 26处。蟒岭地区的萤石矿产于蟒岭燕山期二长花岗岩中,严格受区内三、四级断裂构造控制,矿石呈浅紫色—紫色和无色,少量呈浅绿色,半自形粒状结构、他形粒状结构、交代—溶蚀结构,常见的围岩蚀变有硅化、方解石化等。其形成机制为:燕山晚期富氟的岩浆期后热液沿着断裂通道上行,在其上升运移时还不断萃取交代围岩中F、Ca元素,随着温度极速下降,在氧化环境下于北北西、北东东、近南北向次级断裂中充填交代围岩角砾,形成萤石矿体,矿床类型为低温热液充填型。蟒岭地区成矿地质背景优越,萤石矿成矿物质和构造前提具备,氟化探异常、萤石自然重砂异常发育,指示性良好,矿化线索丰富,找矿标志明显,通过工作扩大矿床规模、实现找矿新突破的潜力巨大。

Geological characteristics and prospecting potential of fluorite deposits in Mangling area,North Qinling Mountains

The Mangling rock mass is located in the hinterland of Qinling mountains and across the Henan and Shaanxi province,which is rich in mineral resources.The tectonic structure is located in the north Qinling tectonic belt of the Qinling complex continental orogenic belt. The metallogenic zone belongs to the metallogenic zone of iron,copper,molybdenum,tungsten,lead and zinc fluorite in the yanshanian period of muhuguan,northern qinling,and the fluorite mineralization in the area is produced in the monzonitic granite of yanshanian,and which is strictly controlled by the third-level and fourth-level fault structures in the area. Ore is mainly light purple,purple and colorless and a small amount light green with semi - automorphic granular structure,other granular structure and metasomatic - dissolution structure.Its common wall rock alteration includes silicification,calcite and so on.The formation mechanism is as follows:The fluorine-rich post-magmatic hydrothermal of late yanshanian goes up along the fracture of the channel,during the ascending migration,F and Ca elements in the surrounding rock were extracted continuously,then fill the replacement surrounding rock breccia in the nw,ndong,nne and nw secondary faults under the oxidized environment to form fluorite ore bodies,with the rapid decrease of temperature. With a superior mineralization geological background,the mineralization materials and structural preconditions of fluorite are available,the fluorine geochemical anomaly and fluorite natural heavy sand anomaly are well developed,the indicators are good,the mineralization clues are abundant,and the prospecting indicators are obvious,so there is great potential to expand the deposit scale and achieve new breakthroughs in prospecting through work.