| 雄村铜金矿床Ⅱ号矿体侵入岩-火山岩的地球化学特征：对岩石成因及构造背景的约束 |
| 点此下载全文 |
| 引用本文：黄勇,唐菊兴,郎兴海,张丽,陈渊.2011.Geochemical characteristics of intrusive and volcanic rocks in No.Ⅱ ore body of Xiongcun copper-gold deposit, Tibet: Constraints on rock genesis and tectonic setting[J].Mineral Deposits,30(2):361~373 |
| Hits: 2897 |
| Download times: 2562 |
|
| 基金项目:本文得到国家973项目（编号：2011CB403103）、中央公益性行业科研专项“西藏甲玛斑岩铜多金属矿科学基地研究”课题(编号：200911007-02)、青藏专项(编号：1212010818089；1212010012005)共同资助 |
|
| 中文摘要:雄村斑岩型铜金矿床是近年在冈底斯带南缘发现的一个与中生代岩浆活动有关的岛弧型斑岩铜金矿床。文章对雄村Ⅱ号矿体安山质凝灰岩、角闪闪长玢岩、含溶蚀状石英斑晶的石英闪长玢岩和晚期含粗粒石英斑晶的石英闪长玢岩进行了岩石学、岩石化学研究，结果表明：这些岩石的w(SiO2)介于61.97%～66.57%，w(Al2O3)为16.40%～17.57%，w(MgO)为1.07%～2.89%，w(TFeO)介于1.75%～5.72%，均属钙碱性系列。Mg#介于19.44～37.46，平均28.79，w(TiO2)<1%。稀土元素总量为35.51×10-6～103.85×10-6，LaN/YbN比值为1.76～6.57，轻稀土元素富集。含矿火山岩和侵入岩明显富集Rb、Sr、Th、U等LILE元素，亏损Nb、Ta、Ti、Y等HFSE元素，无铕异常或弱负铕异常，无铈异常，矿化火山岩、侵入岩具有典型岛弧火山岩的特征。岩石学、岩石化学、微量元素研究表明，火山岩、侵入岩形成于中生代雅鲁藏布新特提斯洋向北部拉萨地体俯冲的岛弧环境，岩浆起源于地幔的部分熔融。 |
| 中文关键词:地球化学 斑岩型铜金矿 岩石成因 构造背景 雄村 西藏 |
| |
| Geochemical characteristics of intrusive and volcanic rocks in No.Ⅱ ore body of Xiongcun copper-gold deposit, Tibet: Constraints on rock genesis and tectonic setting |
|
|
| Abstract:The Xiongcun porphyry copper-gold deposit is located in southern Gangdise belt. The ore deposit is related to Jurassic magmatic event. Petrographic and geochemical studies of andesitic volcanic rock, hornblende diorite porphyrite, corroded quartz phenocrysts-bearing quartz diorite porphyrite and late coarse-grained corroded quartz phenocrysts-bearing diorite porphyrite show that the tuff and intrusive rocks of No.Ⅱ ore body are of calc-alkaline series, with w（SiO2） ranging from 61.97% to 66.57%, w（Al2O3) ranging from 16.40% to 17.57%, w（MgO) ranging from 1.07% to 2.89%, and w（TFeO) ranging from 1.75%～5.72%. Mg# values vary from 19.44～37.46, 28.79 on average, w（TiO2) values are lower than 1%. Total REE concentrations range from 35.51×10-6 to 103.85×10-6, LaN/YbN ratios vary from 1.76 to 6.57, with the enrichment of LREE. Mineralized tuff and intrusion are enriched with LILE elements such as Rb, Sr, Th and U, and depleted in HFS elements such as Nb, Ta, Ti and Y, with no or weak negative Eu anomalies and no Ce anomalous features. Petrographic and geochemical studies indicate that volcanic and intrusive rocks are products of Tethys subduction to North Lhasa tectonic body, and magma originated from partial melting of the mantle. |
| keywords:geochemistry, porphyry copper-gold deposit, rock origin, tectonic setting, Xiongcun, Tibet |
| View Full Text View/Add Comment Download reader |
|
|
|
