摘要
广东云浮大降坪矿床为华夏板块西缘成冰系之后发育的储量超过2×1011kg的超大型硫铁矿矿床,前人根据矿区地质特征和地球化学研究,确证了该矿床的热水沉积成因。该矿床黄铁矿硫同位素显示出较大的硫同位素分异(-26.7‰~24.5‰,极差为51.2‰),与典型的热水沉积矿床有较大差别,已提出的几种成因模式尚不能圆满解释该矿床明显不均一的硫同位素特征。本文通过对不同矿体剖面的地质观察、系统的岩矿鉴定、单矿物硫同位素和微区硫同位素测试,将大降坪矿床的黄铁矿划分为3个成因阶段6种类型,进而对大降坪矿床热水沉积成因模式进行了修正。
The Dajiangping deposit,formed in the western margin of the Cathaysia plate after the Cryogenian,in the Yunfu area,Guangdong Province,China,is a large-scale pyrite deposit with reserves of more than 200 million tons.Based on the geological and geochemical characteristics of the deposit,previous researchers have confirmed its genesis of hydrothermal sedimentary. The pyrites of the deposit have extremely heterogeneous sulfur isotopic characteristics(-26. 7‰~24. 5‰,range: 51. 2‰),indicating relatively large differences comparing to the sulfur isotopes of the typical hot water deposition ore deposits. This sulfur isotopic characteristics could not be perfectly explained by some published genetic models. Based on geological observation of various profiles of various orebodies, systematic identification of rocks and minerals,as well as sulfur isotopic analysis of sulfide mineral separates,and in-situ analysis of sulfur isotopes of sulfide by using Nano-SIMS,the pyrite in the Dajiangping deposit has been classified into six types formed in three genetic stages,and then the hydrothermal sedimentary genetic model of the Dajiangping deposit has been modified.
出处
《矿物学报》
CAS
CSCD
北大核心
2018年第4期406-419,共14页
Acta Mineralogica Sinica
基金
国家自然科学基金项目(批准号:41530210
41072054)
关键词
热水沉积成矿作用
微区硫同位素
铅锌分异
大降坪硫铁矿矿床
hydrothermal sedimentary mineralization
in-situ Nano-SIMS sulfur isotope analysis
lead-zinc differentiation
dajiangping pyrite deposit