西藏色布塔铜钼矿床中辉钼矿Re-Os定年及其成矿意义

Molybdenite Re-Os Isotope Age and Metallogenic Significance of Sebuta Copper Molybdenum Deposit in Tibet

色布塔铜钼矿床位于冈底斯成矿带北部,具有细脉浸染状矿化,围岩蚀变发育等斑岩型铜钼矿床特征。本文使用电感耦合等离子体质谱仪TJA X-series ICP-MS对色布塔铜钼矿床的花岗斑岩中的辉钼矿进行Re-Os同位素定年研究,获得了6件样品的模式年龄为87.52±1.35～88.8±1.26Ma,等时线年龄为88.8±1.5Ma。本文研究成果表明,色布塔铜钼矿成矿时代为晚白垩世早期,属燕山期构造-岩浆活动的产物。

Sebuta Cu-Mo deposit is located in the north of Gangdese metallogenic belt. It has the characteristics of porphyry copper-molybdenum deposit such as veinlets disseminated mineralization, wall-rock alteration and development etal. This article uses inductively coupled plasma mass spectrometry TJA X-series ICP- MS/or the molybdenite Re-Os isotopic dating of granite porphyry in Sebuta, obtained six samples model age is 87. 52 ± 1. 35～88. 8 ± 1. 26Ma, and isochron age is 88. 8 ± 1. 5 Ma. It shows that the mineralization age of sebuta copper-molybdenum is early Late Cretaceous, and it is the tectonic-magmatic product of Yanshan stage.