冈底斯斑岩铜矿带冲江及驱龙含矿斑岩体锆石ELA-ICP-MS及SHRIMP定年对比研究  

COMPARISON OF ELA-ICP-MS AND SHRIMP U-PB ZIRCON AGES OF THE CHONGJIANG AND QULONG ORE-BEARING PORPHYRIES IN THE GANGDESE PORPHYRY COPPER BELT

作　　者：莫济海[1,2] 梁华英[1] 喻亨祥[3] 谢应雯[1] 张玉泉[1] 

机构地区：[1]中国科学院广州地球化学研究所 [2]中国科学院研究生院,北京100039 [3]桂林工学院

出　　处：《大地构造与成矿学》2006年第4期504-509,共6页Geotectonica et Metallogenia

基　　金：国家自然科学基金项目(40472049);中国科学院广州地球化学研究所创新项目(GIG-CX-040-03)资助.

摘　　要：利用ELA-ICP-MS分析技术对冈底斯斑岩铜矿带冲江及驱龙含矿斑岩体进行锆石U-Pb年龄测定,所得到的年龄分别为14.0±0.2Ma和17.0±0.2Ma。两个含矿岩体锆石ELA-ICP-MSU-Pb年龄和SHRIMP年龄在误差范围内基本一致。冲江含矿斑岩体成岩成矿可分为两期,每期成岩成矿时间跨度约1Ma;驱龙含矿斑岩体成岩成矿时间跨度约为1Ma。New zircon U-Pb ages of the Chongjiang and the Qulong ore-bearing porphyries in the Gangdese porphyry copper belt are analyzed by using ELA-ICP-MS dating technique. The ages for the early stages of both Chongjiang and the Qulong ore-bearing porphyries are 14.0 ± 0.2 Ma and 17.0 ± 0.2 Ma, respectively. Here the zircon ELA-ICP-MS U-Pb ages are similar to the SHRIMP U-Pb ages within error, suggesting that the ELA-ICP-MS method can be used to precisely date the ages of young zircon grains. The data also imply that the Chongjiang orebearing porphyry may undergo two stages of magma-ore-forming processes and the lifespan of each stage lasts about 1 Ma, and that the lifespan of the Qulong magmatic ore-formation system lasts about 1 Ma.

关 键 词：冈底斯斑岩铜矿带 含矿斑岩 ELA—ICP—MS 锆石年龄 西藏 

分 类 号：P597[天文地球—地球化学]