陕西秦岭东部地区中生代钼、铜矿床时空分布规律、控矿因素及找矿潜力分析

发布时间：2018-02-04 04:04

本文关键词： 地球化学钼、铜矿床控矿因素时空分布规律成矿潜力陕西东部　出处：《矿床地质》2016年04期 　论文类型：期刊论文

【摘要】：陕西秦岭东部地区中生代钼、铜矿床成矿类型齐全,有斑岩型、斑岩-矽卡岩型、矽卡岩型、石英脉型和碳酸岩脉型。钼矿床主要分布在小秦岭地区,有向西秦岭过渡和向南秦岭延伸的趋势;铜矿床主要分布在南秦岭地区。除碳酸岩脉型钼矿床外,这些钼、铜矿床多与花岗质小岩体具有密切的成因联系,不受容矿地层的限制,成矿时代主要集中在晚三叠世—早侏罗世和晚侏罗世2个阶段,与共生岩体的成岩时代多数相同,个别相差在10 Ma内。赋矿岩体多受近EW向与NE向或NW向断裂构造交汇部位的控制,与钼矿床有关的成矿岩体显示高硅(w(Si O2)71%)、高钾(K2O/Na2O1)、中铁(w(TFe)=0.13%~2.45%)特征,而与铜矿床有关的岩体相对低硅(70%w(Si O2)62%)、中钾(K2O/Na2O0.88)、高铁(w(TFe)=1.9%~4.8%)。矿石、岩体和地层的S、Pb、Sr、Nd同位素组成显示,除晚三叠世碳酸岩脉型和石英脉型钼矿的成矿物质来源于Ⅰ型富集地幔外,早侏罗世—晚白垩世斑岩-矽卡岩型及石英脉型钼、铜矿成矿物质以壳幔混源为主,但铜矿比钼矿具有更多的幔源物质。地质和地球化学特征指示,南秦岭和北秦岭地区有形成斑岩型铜、钼矿床的有利条件,也有不利因素,不利因素导致南秦岭和北秦岭地区浅部不易形成大型斑岩铜、钼矿床,但形成小-中型铜、钼矿床的潜力大。
[Abstract]:The metallogenic types of Mesozoic molybdenum and copper deposits in eastern Qinling, Shaanxi Province are complete, including porphyry type, porphyry skarn type, skarn type, quartz vein type and carbonatite vein type. Molybdenum deposits are mainly distributed in Xiaoqinling area. There is a trend of transition to the West Qinling Mountains and extension to the South Qinling Mountains; Copper deposits are mainly distributed in the South Qinling area. Except carbonatite vein molybdenum deposits, these molybdenum and copper deposits are closely related to granitic rock bodies and are not restricted by ore-bearing strata. The metallogenic age is mainly concentrated in the late Triassic-early Jurassic and the late Jurassic stages, which are the same as most of the diagenetic ages of the symbiotic rock mass. Some of them are within 10 Ma. The ore-bearing rock bodies are controlled by the intersection of near-EW and NE or NW-trending faults. The ore-forming rock bodies related to molybdenum deposits show the characteristics of high silicon, high K _ 2O / Na _ 2O _ 1, and 0.13 ~ (0.13) ~ 0.13 ~ 0.45). The relative low Si ~ (2 +) ~ (70) Si / O ~ (2 +) and K _ 2O / Na _ 2O _ (0.88) are related to the copper deposit. The isotopic composition of SbPb-Sr-Ndn in ore, rock mass and strata is shown in 1.9H ~ (-1) ~ (th) ~ (th) ~ (th) ~ (th) ~ (th) ~ (th) ~ ((th)). In addition to the late Triassic carbonatite vein type and quartz vein type molybdenum ore-forming material originates from type I enriched mantle, early Jurassic-late Cretaceous porphyry skarn type and quartz vein type molybdenum, the ore-forming material of copper deposit is mainly crust mantle mixed source. The geological and geochemical characteristics indicate that the South Qinling and North Qinling areas have favorable conditions for the formation of porphyry copper and molybdenum deposits, and there are also some unfavorable factors. It is difficult to form large porphyry copper and molybdenum deposits in the shallow part of the South Qinling and North Qinling regions, but there is a great potential for the formation of small to medium copper and molybdenum deposits.
【作者单位】：西北有色地质矿业集团有限公司;长安大学;西北有色地质勘查局七一三总队;西北有色地质勘查局七一二总队;
【基金】：“十二五”国家科技支撑计划课题(编号:2011BAB04B05) 西北有色地质矿业集团博士后项目国土资源部公益性行业科研专项(编号:201111007-3)联合资助
【分类号】：P618.41;P618.65
【正文快照】： have genetic relations with small granitic intrusions,and have no clear controlling influence from strata.The ore-forming ages of these deposits are mainly in two epochs:Late Triassic-early Jurassic and late Jurassic,close to therock-forming age of the o

【相似文献】