中文摘要:江西冷水坑矿床是国内外少见的斑岩型银铅锌矿床之一.文章研究了冷水坑矿田内的侵入岩及其围岩的岩石学、岩石化学、Sr和Nd同位素特征,结合岩体产出的大地构造环境,指出:①该矿田的含矿斑岩属于钙碱性系列,具有高SiO2、富K2O和富MnO、低Na2O的特点,富集轻稀土元素,轻、重稀土元素分馏较强,铕负异常明显;②与非含矿斑岩相比,该含矿斑岩具有较高的Sr初始值(0.71327)和较低的εNd(t)值(-7.5～-10.2),其两阶段钕模式年龄t2DM为1 535～1 760 Ma.该含矿斑岩起源于武夷区基底变质岩,由地壳物质重融而成,同时有少量地幔物质的混染;③该含矿斑岩与其他侵入岩及围岩为同源岩浆在不同阶段演化的产物,均来源于地壳重熔,同属于S型花岗岩;④该含矿斑岩形成于陆内造山挤压环境.冷水坑矿田的含矿斑岩与中国斑岩型铜矿的含矿斑岩具有较大的差异.
Abstract:The Lengshuikeng deposit in Jiangxi Province is one of the porphyry type Ag_Pb_Zn deposits rarely seen in China and abroad. In this paper, the authors studied the lithology, petrochemistry, and Sr, Nd isotopes of the intrusion and its wall rock in the Lengshuikeng deposit. The following conclusions have been reached: ① The ore_bearing porphyry belongs to calc_alkali rock with high SiO2, K2O, MnO and low Na2O. The enrichment of LREE and the LREE/HREE fractionation are obvious, with distinct negative Eu anomaly. ② Compared with barren porphyries, the ore_bearing porphyry has high ISr (0.71327) and low εNd(t) (-7.5～-10.2). The two phase Nd model age ( t2DM) is 1 535～1 760 Ma. The porphyry was derived from the metamorphic basement in Wuyi area and formed by lithospheric partial melting with some mantle contamination. ③ The ore_bearing porphyry and other intrusions as well as the wall rocks in the Lengshuikeng ore deposit were produced at different evolutionary stages of the consanguineous series, and originated exclusively from lithosphere remelting, thus belonging to S type granite. ④ Lengshuikeng ore_bearing porphyry was formed in an extrusion environment during inland orogeny, hence remarkably different from other ore_bearing porphyries in China.
keywords:geology, Ag_Pb_Zn deposit, porphyry type, tectonic environment, Lengshuikeng, Jiangxi Province
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基金项目:江西省地质矿产局912大队与中国地质科学院矿产资源研究所合作项目《江西冷水坑银铅锌多金属矿成矿系统及隐伏矿预测研究》
引用文本：
左力艳,孟祥金,杨竹森.2008.冷水坑斑岩型银铅锌矿床含矿岩系岩石地球化学及Sr、Nd同位素研究[J].矿床地质,27(3):0ZUO LiYan,MENG XiangJin,YANG ZhuSen.2008.Petrochemistry and Sr, Nd isotopes of intrusive in Lengshuikeng porphyry type Ag-Pb-Zn deposit[J].Mineral Deposits27(3):0
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