中文摘要:文章对西藏玉龙斑岩铜钼矿含矿斑岩体及外围岩体进行了系统的锆石Hf同位素原位分析,测得玉龙含矿斑岩体的176Hf/177Hf值为0.282 681~0.282 884,εHf(t)为1.60~4.86,矿区外围北部甘龙拉石英二长斑岩岩体176Hf/177Hf值为0.282 812~0.282 884,εHf(t)为2.39~4.92,矿区外围南部的纳加扎Y3石英二长斑岩岩体176Hf/177Hf值为0.282 449~0.282 894,εHf(t)为0.81~10.51,Hf同位素测试结果与亏损地幔地球化学储库的Hf同位素特征较为相似,表明本区成矿斑岩的源岩或源区可能来自亏损地幔,结合区域地球物理资料,认为玉龙斑岩铜矿带斑岩体是由软流圈上涌及其诱发的强烈底侵作用,使得本区地壳增厚继而发生部分熔融而形成。
Abstract:The Yulong ore deposit is a superlarge porphyry copper-molybdenum deposit in the Sanjiang region. Zircon in-situ analysis gives 176Hf/177Hf ratios ranging from 0.282 681 to 0.282 884, and the average εHf (t) of 1.60~4.86 (Yulong rock); 176Hf/177Hf ratios ranging from 0.282 812 of 0.282 884, and the average εHf (t) values of 2.39~4.92 (Ganlongla rock); 176Hf/177Hf ratios ranging from 0.282 449 to 0.282 894, and the average εHf (t) values of 0.81~10.51 (Najiazha Y3 rock). These data indicate that the source rook or source region of the Yulong porphyry copper-molybdenum belt might have been the depleted upper mantle. Combined with geophysical data, the authors hold that, along with the asthenosphere upwelling, the Yulong porphyry rocks might have been derived from the partial melting of the thickened crust resulting from the underplating.
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基金项目:本文为中央级公益性科研院所基本科研业务费专项资金(编号K0923)、国家基础研究计划“印度-亚洲大陆主碰撞带成矿作用”973项目(编号2002CB412607)、中国地质大调查项目(编号1212010633903、1212010634002、1212010535804)和西藏玉龙铜业有限股份有限公司勘探项目“玉龙铜矿Ⅰ、Ⅱ、Ⅴ号矿体地质特征及其外围成矿规律和成矿预测研究”共同资助的成果
引用文本:
王成辉,唐菊兴,侯可军,高一鸣,陈建平,郝金华,应立娟,章奇志,刘耀文,凡韬.2011.西藏玉龙铜钼矿区斑岩体Hf同位素特征及其地质意义[J].矿床地质,30(2):292~304王成辉,唐菊兴,侯可军,高一鸣,陈建平,郝金华,应立娟,章奇志,刘耀文,凡韬.2011.Hf isotopic characteristics of Yulong copper-molybdenum porphyry deposit in Tibet and their geological significance[J].Mineral Deposits30(2):292~304
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