地质力学学报2018，Vol.24Issue(3)：341-349,9.DOI:10.12090/j.issn.1006-6616.2018.24.03.036
西藏尕尔勤铜矿床花岗闪长斑岩地球化学特征及成矿作用研究
GEOCHEMICAL CHARACTERISTICS OF GRANODIORITE PORPHYRY AND MINERALIZATION STUDY IN THE GAERQIN COPPER DEPOSIT, TIBET
摘要
Abstract
The rare earth elements (REEs) in granodiorite porphyry and zircon from the Gaerqin copper deposit of Tibet, China, were geochemically traced, and the mineralization was also studied.The total levels of REEs in granodiorite porphyry varied slightly ( ΣREE＝48.64 ×10 -6~78.12 ×10 -6) with LREE/HREE＝8.67~11.68.All samples were featured by a right-leaning distribution with enrichment in light REEs ( LREEs) and depletion in heavy REEs ( HREEs), δEu changed from weak negative anomaly to weak positive anomaly, which is due to the gradual weakening of negative Eu anomalies caused by crystallization differentiation and a weak positive Eu anomaly in the process of the partially remelting growth of the angled magma in the crust.The zircon was found with typical oscillatory zones, large total REE levels ( ΣREE ＝735.78 ×10 -6~6792.10 ×10 -6), LREE depletion, HREE enrichment, evident Ce positive anomaly and weak negative Eu anomaly.This is because under the action of mantle fluid, heavy rare earth elements and Ce are more likely to enter the lattice of zircon than other light rare-earth elements.The weak negative abnormality of Eu is caused by oxidation and leaching of the late diagenetic rock mass.Comprehensive analysis reveals that the mantle fluid action endowed the granodiorite porphyry with the characteristics of crust-mantle mixing or even ore-formation.Meanwhile, the matter-energy exchange between magma and surrounding rocks accounted for the metamorphic sandstone ore-formation.关键词
花岗闪长斑岩/锆石/稀土元素/尕尔勤/西藏Key words
granodiorite porphyry/zircon/rare earth elements/Gaerqin/Tibet分类
天文与地球科学引用本文复制引用
何阳阳,温春齐,刘显凡..西藏尕尔勤铜矿床花岗闪长斑岩地球化学特征及成矿作用研究[J].地质力学学报,2018,24(3):341-349,9.基金项目
国土资源部公益性行业科研专项项目(201011013) （201011013）
四川省教育厅科研项目(17ZB0223) （17ZB0223）
