摘要
通过系统研究纳日贡玛含矿斑岩体的地质、地球化学特征,深入剖析了含矿斑岩体的形成机制及其成矿模式。研究结果表明,纳日贡玛含矿斑岩体与藏东玉龙含矿斑岩体同属一个成矿带,是喜玛拉雅运动第一幕(40～35Ma)的产物。斑岩体主体部分是黑云母二长花岗斑岩,少部分为花岗闪长斑岩,围岩为中二叠世尕笛考组(P2gd)的玄武岩。含矿斑岩为同源岩浆经长期演化、多期侵位而形成的复式岩体,它们多沿区域性断裂呈串珠状断续分布。斑岩体的内外接触带以及各种裂隙是主要矿体的产出部位。岩体侵入后,由于热重力扩散作用和Cu、Mo元素化学性质的差异,导致成矿元素在空间分布上具有分带性,并且显示出下部富钼、上部富铜的分布特征。研究结果对于深入认识该区的成矿地质条件、成矿规律和指导下一步勘探均具有重要的参考价值。
We study the geochemical characteristic of the ore-bearing porphyry body in Narigongma and analyze its formation mechanism as well as the mineralization pattern.The results indicate that,Narigongma ore-bearing porphyry body and Tibet Yulong ore-bearing porphyry body belong to the same mineralization belt and is result of the first episode （40-35 Ma） of the Himalayan movement.The main part of porphyry body is the biotite adamellite porphyries,with a small amount of granodiorite-porphyry and the surrounding rock being the Permian Gadikao group （P2gd） basalt.The ore-bearing porphyry is the composite rock body formed from the comagma undergoing a long-term evolution and a multi-stage emplacement,discontinuously distributing in a moniliform pattern along the regional fault.The ore body mainly appears in the contact zone between inside and outside of the porphyry and in various fractures.The Narigongma ore deposit is the porphyry type of copper molybdenum ore deposit.It has a typical porphyry ore deposit and the hydrothermal alteration characteristic.After the rock mass invasion,as a result of the thermogravimetry strength diffusion,the difference in chemical property between Cu and Mo causes the ore-forming elements to have a spatial zonation,characterized by that the bottom is rich in molybdenum and the upper is rich in copper.
出处
《西北地质》
CAS
CSCD
2010年第3期28-35,共8页
Northwestern Geology
基金
青海纳日贡玛-拉美曲地区矿产远景调查项目(矿调[2004]2-1号
矿调[2005]2-1号
矿调[2006]2-1号)
关键词
铜钼矿床
花岗斑岩
成矿模式
纳日贡玛
copper molybdenum deposit
granite-porphyry
mineralization pattern
Narigongma
