摘要
红山Cu多金属矿床位于滇西北义敦岛弧南端的中甸岛弧,一直以来被认为是印支期夕卡岩型矿床。但近年研究发现,矿区内还发育有燕山晚期斑岩型Cu-Mo矿化作用。本文首次在红山矿区发现了燕山晚期的花岗斑岩,花岗斑岩锆石LA-ICP-MS U-Pb定年研究确定其年龄为(81.1±0.5)Ma,与斑岩型Cu-Mo矿化年龄(77±2 Ma,辉钼矿Re-Os等时线年龄)在误差范围内非常接近,成岩与成矿作用之间具有密切的时空成因联系。红山Cu多金属矿床燕山晚期花岗斑岩成岩年龄与义敦岛弧造山后伸展环境下所形成的花岗岩浆成岩时代峰期(80 Ma左右)相一致,表明中甸红山地区除存在与俯冲作用密切相关的印支期Cu多金属成矿作用外,还存在燕山晚期形成于造山后伸展环境的花岗斑岩型Cu-Mo成矿作用。
Hongshan Cu-polymetallic deposite, which has long been considered as an indosinian skarn-type Cu-polymetallic deposit, is located in Zhongdian arc, south of Yidun arc, northwest Yunnan, China. Recent researches show that there is late Yanshan Epoch porphyry Cu-Mo mineralization in Hongshan deposit area too. In this paper, late Yanshan Epoch granite porphyry in Hongshan deposit area was found for the first time. LA-ICP-MS zircon U-Pb dat- ing of the granite porphyry yields crystallization age of 81.1 ＋ 0. 5 Ma, which is very close to a previously reported molybdenite Re-Os isoehron age of porphyry Cu-Mo mineralization （77 ＋ 2Ma）. It means that there is a consistent spatial-temporal relationship between the granite porphyry and the porphyry Cu-Mo mineralization. The age of the late Yanshan Epoch magmatism（ 81.1 ＋ 0.5 Ma） in the Hongshan Cu-polymetallic deposit is consistent with the peak period（around 80Ma） of the granites magmatism under posorogenic extensional environment in Yidun arc. So it is suggested that there is not only Indosinian skarn-type Cu-polymetaUie mineralization in Hongshan area, which is closely related to the subduetion of oceanic crust, but also the late Yanshan Epoch porphyry Cu-Mo mineralization under post-orogenic extensional environment.
出处
《矿物学报》
CAS
CSCD
北大核心
2011年第3期315-321,共7页
Acta Mineralogica Sinica
基金
中国科学院知识创新工程重要方向项目群项目(KZCX2-YW-Q04-01)
国家自然科学基金项目(40873037)
矿床地球化学国家重点实验室自主创新项目
作者简介
王新松，男，1986年生，在读硕士，地球化学专业．E—mNl：gyigxsw@hotmail．com
通讯作者，E-mail：bixianwu@rip．gyig．ac．cn
