晋东北伯强—耿庄矿区成矿岩体的锆石微量元素特征

Characteristics of Zircon Trace Elements in Ore-forming Rock Mass in the Boqiang–Gengzhuang Mining Area, Northeastern Shanxi

锆石是中酸性岩浆岩中常见的副矿物,其广泛地被应用于年代学、同位素示踪和岩浆物理化学条件的研究。论文对山西五台山北麓伯强—耿庄矿区内成矿同期的石英斑岩、斑状花岗岩和二长岩中的锆石微量元素进行测定,应用锆石Ti温度计和Ce4+/Ce3+比值计算其氧逸度。结果显示,研究区内锆石样品呈现重稀土元素强烈富集,轻稀土元素亏损,未见明显Eu异常,但可见Ce异常明显,整体呈左倾配分模式,多数锆石在600℃~900℃之间结晶,主要集中在800℃左右,大多数锆石在HM和FMQ缓冲线之间,离散度较大,均值较小,不利于大型Cu、Au矿床的形成。

Zircon is a common accessory mineral in moderately acidic magmatic rocks and has been widely used in the study of chronology, isotope tracer and magmatic physicochemical conditions. In this paper, the trace elements of zircon in the ore-forming contemporaneous quartz porphyry, porphyritic granite and monzoite in the Boqiang Mo-Cu ore deposit at the northern foot of mount Wutai in Shanxi province were determined. The oxygen fugacity of zircon was calculated by using the zircon Ti thermometer and the Ce4+/Ce3+ ratio. Results show that the research area of zircon samples show strong enrichment of heavy rare earth elements, loss of light rare earth element, it did not see clearly Eu but visible Ce anomaly, left-learning distribution pattern on the whole, most zircon crystals between 600℃ to 900℃, mainly concentrated in about 800℃, most of the zircon between HM and FMQ buffer line, discrete degree is bigger, the mean is small, not conducive to the formation of large Cu、Au deposit.