栾川县罗村钼矿成矿地质背景和矿床特征

Metallogenic Geologic Background and Characteristics of Luocun Molybdenum Deposit in Luanchuan County,Henan Province

栾川县罗村钼矿为豫西东秦岭钼成矿带的重要组成部分,地处华北地台-华熊台缘坳陷-卢氏至栾川陷褶束内。区内太华群变质岩和熊耳群火山岩广泛发育,构造活动强烈,岩浆活动频繁,成矿地质条件有利。通过对矿区地质及矿床地质特征的分析,认为罗村斑岩体由中心细粒花岗斑岩、中环带角砾岩和外环带花岗闪长岩组成,罗村钼矿主要位于中环带角砾岩中。通过综合分析,认为罗村钼矿床形成于燕山中—晚期,陆内造山俯冲作用导致下地壳熔融与地幔楔分熔,形成富钼熔浆。其沿黑沟-栾川断裂带多次上侵,在罗村附近形成斑岩体。晚期岩浆期后热液对中环带角砾岩进行充填和交代,形成斑(角砾)岩型罗村钼矿床。

Luocun molybdenum deposit of Luanchuan county is an important part of the eastern Qinling molybdenum metallogenic belt in western Henan,it is located on the Lushi-Luanchuan depression folds bundle,that is a part of the Huaxiong margin depression in the North China Platform.The volcanic rocks of the Xiong＇er Group and the metamorphic rocks of Taihua Group in the research area distribute extensively.For the intense tectonic movements and frequent magmatic activities,it is considered to be a favorable metallogenic area.Through the study of the characteristics of the geology in mining area and deposit,we know the Luocun granite-porphyry bodies are composed of fine granite-porphyry centre,breccia middle zones and Granodiorite rock outer zones,and the Luocun molybdenum deposit occur in breccia middle zones.It is concluded that the Luocun molybdenum deposit was formed during Later Yanshanian to middle Yanshanian.The intracontinental orogenesis and subduction result in the fusion of lower crust and the liquation of mantle wedge form the molybdenum rich magma.Its uptrusion into Heigou-Luanchuan fault zones are more than once,and formed granite-porphyry body near the Luocun.postmagmatic hydrothermal solution filling-metasomatism in breccia middle zones in the later period,and form the porphyry type（breccia type） Luocun molybdenum deposits.