摘要
黄石桥地区地处萍乡—广丰叠接断裂带与驿前—黄岗山断裂带之间,饶南坳陷东段以北。为探讨地区中酸性岩体岩石成因及成矿潜力,以黄石桥地区中酸性岩体为研究对象,进行岩石学、岩石地球化学分析研究。结果显示:黄石桥中酸性岩的岩石类型为石英闪长玢岩和花岗闪长斑岩;具低Ti(ω(TiO_(2))=0.31%~0.65%)、富Si(ω(SiO_(2))=60.8%~68.4%)、富Al(ω(Al_(2)O_(3))=13.9%~17.6%)、高K(ω(K_(2)O)=2.68%~4.15%)、高Na(ω(Na_(2)O)=2.44%~3.91%)的特点,属高钾钙碱性系列,具准铝质—弱过铝质的特征;岩石轻稀土强烈富集(La/Yb)N值为7.23~13.7,铕异常不明显(Eu/Eu^(*)=1.02~1.32),富集Rb、Ba、U、K、Sr、Hf,相对亏损Th、Nb、Ta、Zr、P、Ti。矿物学及岩石地球化学分析表明,黄石桥中酸性岩的成因类型为埃达克质I型花岗岩,起源于由挤压向伸展转换环境下的玄武质富含金红石榴辉岩的部分熔融岩浆,且具有较大的斑岩型铜矿成矿潜力。
Huangshiqiao area is located between the Pingxiang-Guangfeng superimposed fault zone and the Yiqian-Huanggangshan fault zone,north of the eastern section of the Raonan Depression.In order to explore the petrogenesis and mineralization potential of the intermediate-acid rock mass in the area,the intermediate-acid rock mass in Huangshiqiao area was taken as the research object,and the petrology and petrogeochemical analysis were carried out.The results showed that the rock type of the Huangshiqiao intermediate-acid rock is quartz bleach Porphyrite and granodiorite porphyry;with low Ti((TiO_(2))=0.31%~0.65%),rich Si((SiO_(2))=60.8%~68.4%),rich Al((Al_(2)O_(3))=13.9%~17.6%),high K((K_(2)O)=2.68%~4.15%),high Na((Na_(2)O)=2.44%~3.91%)characteristics,belong to high potassium calcium alkaline series,with quasi-aluminum-weak peraluminum Qualitative characteristics;the rock is strongly enriched in light rare earths(La/Yb)N values ranging from 7.23 to 13.7,and the europium anomaly is not obvious(Eu/Eu^(*)=1.02~1.32),enriched in Rb,Ba,U,K,Sr,Hf,Relative loss Th,Nb,Ta,Zr,P,Ti.Mineralogy and petro-geochemical analysis show that the genetic type of the acidic rocks in Huangshiqiao is the adakitic type I granite,which originated from the basaltic magma rich in rutile garnet pyroxene in the transition from compression to extension.And has a large porphyry copper deposit potential.
作者
胡浩
王健
罗宇阳
毛卫东
胡斌
HU Hao;WANG Jian;LUO Yuyang;MAO Weidong;HU Bin(No 268 Team,Jiangxi Bereau of Nuclear Geology;Natural Resources Bureau of Yushan County)
出处
《现代矿业》
CAS
2021年第5期33-38,44,共7页
Modern Mining
关键词
中酸性岩体
岩石成因
构造背景
intermediate—acid intrusive rocks
petrogenesis
tectonic setting
