矿床地质2017，Vol.36Issue(1)：25-37,13.DOI:10.16111/j.0258-7106.2017.01.002
东天山天宇铜镍硫化物矿床磁黄铁矿Re-Os同位素物质来源示踪
Re-Os isotopic analysis of pyrrhotite from Tianyu Cu-Ni sulfide deposit in Eastern Tianshan Mountains, Xinjiang: Constraints on sources of ore-forming materials
摘要
Abstract
The Tianyu Cu-Ni sulfide deposit is composed of spatially adjacent disseminated orebody and massive orebody,with the former formed earlier than the latter.In this study,the authors used isotopic dilution Tritonplus to determine the Re-Os isotopic ratios of pyrrhotite from the disseminated ore and the massive ore.In the disseminated ore,the Re content is from 11.82 × 10-9 to 45.28 × 10-9,the Os content is from 0.944 × 10-9 to 8.528 × 10-9,the initial 187Os/188Os ratio is from 0.885 to 2.332,and γOs is from 607 to 1763.In massive ore,the Re content is from 49.38 × 10-9 to 315.10 × 10-9,the Os content is from 0.191 × 10-9 to 42.420 × 10-9,the initial 187Os/188Os ratio is from 0.654 to 3.322,and γOs is from 423 to 2555.Element content,isotopic composition and characteristic values of Re and Os indicate that the ore-forming material in the Tianyu ore deposit was a mixed source of the crust and the mantle,and the massive ore experienced a higher degree of crustal contamination than the disseminated ore.Alteration of tremolite,serpentine and chlorite is developed in the disseminated ore,which indicates post-magmatic hydrothermal activity.In contrast,the massive ore does not show obvious magmatic hydrothermal alteration.Re-Os isotopic characteristics of the massive ore might have resulted from direct interaction with crustal rocks.As a result,crustal contamination was developed both in the deep magma chamber and at the present position of the orebody.关键词
地球化学/磁黄铁矿/LA-ICP-MS/Re-Os同位素/铜镍硫化物矿床/天宇/东天山Key words
geochemistry/pyrrhotite/LA-ICP-MS/Re-Os isotope/copper-nickel sulfide deposit/Tianyu/Eastern Tianshan Mountains分类
天文与地球科学引用本文复制引用
段士刚,蒋宗胜,张作衡,李凤鸣,任雅琼..东天山天宇铜镍硫化物矿床磁黄铁矿Re-Os同位素物质来源示踪[J].矿床地质,2017,36(1):25-37,13.基金项目
本文为中央科研院所基本科研业务费项目(编号:K1202)、国家自然科学基金项目(编号:41203035)和地质矿产调查评价项目(编号:1212011220894-2、1212011090300)资助成果 （编号:K1202）
