摘要
在江西省朱溪矿集区张家坞地区发现了黄铜矿化花岗闪长斑岩,岩石中w(SiO 2)为66.60%~66.84%,w(Al 2O 3)为15.64%~16.70%,w(K 2O+Na 2O)为8.76%~9.60%,表明其为过铝质花岗闪长岩类;∑REE为(85.55~101.77)×10^(-6),轻重稀土元素分馏明显,(La/Yb)N值为9.86~16.72,具Eu负异常;富集Rb、Th、U、K等大离子亲石元素,亏损Ta、Nb、P、Ti等元素,w(Sr)为(382.9~529.4)×10^(-6),w(Y)为(7.32~14.33)×10^(-6),w(Yb)为(0.54~1.04)×10^(-6),具有埃达克(质)岩的特征。根据岩石微量元素数据及相关图解分析结果,文章认为由于受岩石圈伸展作用的影响,软流圈上涌,对下地壳产生底劈作用,为下地壳岩石的熔融提供热量使下地壳发生部分熔融,从而导致岩石圈减薄,张家坞花岗闪长斑岩岩浆来源于加厚下地壳部分熔融。研究结果表明,张家坞花岗闪长斑岩具有岩石圈伸展构造背景,基底地层具有较高Cu元素丰度值,发育众多导矿构造,相比于华南地区成矿花岗岩,塔前-大游山地区具有良好的斑岩型铜矿成矿潜力。
Chalcopyrite granodiorite porphyry was found in the Zhangjiawu area of Zhuxi ore concentration area in Jiangxi Province.The rock has silicon(w(SiO 2)=66.60%66.84%),aluminum(w(Al 2O 3)=15.64%16.70%),and alkali(w(K 2O+Na 2O)=8.76%9.60%),and it is a peraluminous granodiorite;ΣREE is(85.55101.77)×10^(-6),(La/Yb)N value is 9.8616.72,the separation of light and heavy rare earth elements is obvious,with negative anomaly of Eu;it is enriched in large ion lithophile elements such as Rb,Th,U,K,loss of Ta,Nb,P,Ti and other elements,and has high w(Sr)((382.9529.4)×10^(-6)),low w(Y)((7.3214.33)×10^(-6)),w(Yb)((0.541.04)×10^(-6)),with the characteristics of adakite.According to the trace element data and related diagrams of the rock,this paper believes that due to the influence of the lithospheric extension,the asthenosphere upwells and produces an undercutting effect on the lower crust,which provides heat for the melting of the lower crust and causes partial melting of the lower crust.As a result of the lithosphere thinning,the Zhangjiawu granodiorite porphyry magma originated from the partial melting of the thickened lower crust.The Zhangjiawu granodiorite porphyry has a lithospheric extensional structure background,the basement strata has a relatively high Cu element abundance value,and many ore-conducting structures are developed,compared with the ore-forming granites in South China,it can be found that Taqian-Dayoushan area has good metallogenic potential of porphyry copper deposit.
作者
王和平
陈祺
欧阳永棚
王淼林
饶建锋
魏锦
WANG Heping;CHEN Qi;OUYANG Yongpeng;WANG Miaolin;RAO Jianfeng;WEI Jin(No.901 Geological Surveying Team,Jiangxi Bureau of Geology and Mineral Exploration and Development,Pingxiang 337000,China;No.912 Team,Jiangxi Bureau of Geology and Mineral Exploration and Development,Yingtan 335001,China)
出处
《合肥工业大学学报（自然科学版）》
CAS
北大核心
2021年第4期526-533,共8页
Journal of Hefei University of Technology：Natural Science
基金
国家自然科学基金资助项目(41802105)
江西省科学技术厅国家科技奖后备培育计划资助项目(20203AEI91004)
江西省地质勘查基金资助项目(20200022,20150013,20100112)
国土资源部公益性行业科研专项资助项目(201411035)
中国地调局地质调查资助项目(12120113065300)
江西省地质矿产勘查开发局地质科研资助项目(赣地矿字[2017]78号)。
关键词
朱溪矿集区
花岗闪长斑岩
埃达克岩
地球化学特征
成矿潜力
Zhuxi ore concentration area
granodiorite porphyry
adakite
geochemical
metallogenic potential
