陕西南郑地区马元锌矿的地球化学特征及成矿时代

Geochemistry and mineralization age of the Mayuan zinc deposit,Nanzheng,southern Shaanxi,China.

马元锌矿带是近年来地质找矿的重要成果之一,资源潜力巨大。矿带位于扬子地台北缘,锌矿化赋存于震旦系灯影组白云岩的层间断裂带中,受地层层位控制,闪锌矿与固体沥青伴生。对闪锌矿进行了Rb-Sr等时线年龄测定,获得马元锌矿的成矿年龄为486Ma左右;根据对矿物C、H、O、S同位素和微量、稀土元素的研究,认为该锌矿的成矿物质来自围岩地层。综合分析表明,该锌矿为赋存于震旦系碳酸盐岩中的MVT层控矿床。

The newly discovered Mayuan zinc deposit is located on the north margin of the Yangtze craton. It occurs in an interformational fault zone of dolostone of the Sinian Dengying Formation. Sphalerite is usually associated with solid bitumen. The sphalerite gives an Rb-Sr isochron age of 486 Ma^＋, showing that the deposit formed in the Caledonian stage. Carbon and oxygen isotope and trace element and R_EE studies of the minerals indicate that the ore-formation materials of the Zn deposit and fluids mainly originated from host rocks. Integrated analysis shows that this zinc deposit is a stratabound MVT deposit hosted in Sinian carbonate rocks.