地质科学2024，Vol.59Issue(6)：1588-1602,15.DOI:10.12017/dzkx.2024.110
岩浆铜镍硫化物矿床中地壳硫的深部来源:来自黄山东矿床的证据
Deep source of crustal sulfur in magmatic Cu-Ni sulfide deposits:Evidence from the Huangshandong deposit
摘要
Abstract
It is a critical question whether the sulfide⁃bearing country rocks play an important role in the sulfide saturation of magmatic copper⁃nickel sulfide deposits.In this paper,semimetals of whole rocks,trace elements and in situ sulfur isotope for sulfide in intrusive rocks,and country rocks of Huangshandong deposit were analyzed to discuss the genesis of pyrrhotites in country rocks of Huangshandong deposit and its contribution to Ni⁃Cu mineralization.The country rocks of Huangshandong intrusion are limestone and carbonaceous slate of Gandun Formation.The sulfides in the carbonaceous slate far away the intrusion are euhedral pyrites,while the sulfides in carbonaceous slate are irregular clumpy pyrrhotites.Compared to the country rocks,pyrrhotites in the intrusive rocks and sulfide ores have lower Co/Ni ratios,higher Se content and lower Pb content.The geochemical compositions of the pyrrhotite in the country rocks from the Huangshandong deposit are similar to the pyrrhotites in the thermal contact metamorphic zone of country rocks in Duluth intrusion,indicating that the pyrrhotite in the Huangshandong country rocks is formed by hydrothermal metasomatism of the original pyrite,rather than the infiltration of sulfide melts from the intrusion.The sulfide in the carbonaceous slate are pyrrhotites,but the sulfide in the limestone is mainly idiomorphic pyrite,indicating that the reducing substances have a promoting effect on the hydrothermal metasomatism of pyrite.The S/Se ratio of the Huangshandong sulfide ores is larger than the mantle range,indicating assimilation of the crustal sulfur.The S isotopes of pyrites in the country rocks of Huangshandong deposit range from-12.25‰ to-11.95‰,while the S isotopes of pyrrhotites in the sulfide ores range from+0.91‰ to+2.10‰,which is obviously different from those of the country rocks,indicating that there is no large⁃scale contamination with country rock in the Huangshandong deposit,and the addition of crust sulfur in the magma is more likely to occur in the deep.关键词
黄山东岩浆铜镍硫化物矿床/磁黄铁矿/直接围岩/同化混染Key words
Huangshandong magmatic sulfide deposit/Pyrrhotite/Country rocks/Crustal contamination分类
天文与地球科学引用本文复制引用
曹盛轩,哈依热提,邓宇峰,韦帅,袁峰,李卫东,谭治雄,韩建军..岩浆铜镍硫化物矿床中地壳硫的深部来源:来自黄山东矿床的证据[J].地质科学,2024,59(6):1588-1602,15.基金项目
国家自然科学基金项目(编号:42272083,U1803113)和第二次青藏高原综合科学考察研究项目(编号:2019QZKK0708)资助 （编号:42272083,U1803113）
