南大西洋赤狐热液区硫化物特征及成矿机制  

Sulfide Characteristics and Metallogenic Mechanism of the Chihu Hydrothermal Field in the South Atlantic Ocean

作　　者：张琦 李兵 刘季花 李传顺 王赛 石学法 ZHANG Qi;LI Bing;LIU Jihua;LI Chuanshun;WANG Sai;SHI Xuefa(First Institute of Oceanography,MNR,Qingdao 266061,China;Key Laboratory of Marine Geology and Metallogeny,MNR,Qingdao 266061,China;Key Laboratory of Deep Sea Mineral Resources Development of Shandong Province,Qingdao 266061,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]海洋地质与成矿作用自然资源部重点实验室,山东青岛266061 [3]山东省深海矿产资源开发重点实验室,山东青岛266061

出　　处：《海洋科学进展》2024年第2期296-311,共16页Advances in Marine Science

基　　金：国家自然科学基金项目(42102103);崂山实验室科技创新项目(LSKJ202203601和LSKJ202204103);中国大洋协会十三五研究课题(DY135-S2-2-06);中央公益性科研院所基本科研业务费专项资金资助项目(2022Q09)。

摘　　要：赤狐热液区是中国科研人员在南大西洋中脊首次发现的拆离断层型热液区。该区位于拆离断层的下盘,目前发现2个热液点,围岩类型为基性玄武岩。利用ICP-OES、ICP-MS、LA-ICP-MS等方法对2019年获得赤狐热液区硫化物样品开展详细的矿物学和地球化学研究,结果显示该区包括块状、角砾状、浸染状三类硫化物。与其他拆离断层型热液区相比,赤狐热液区上2个热液点具有明显不同的化学特征;全岩的主微量、黄铁矿的微量元素以及热液区硫化物的硫同位素特征明显指示,赤狐热液区可能受到基性与超基性岩的共同影响。热液区2个热液点的差异指示了同一个热液系统不同时期产出硫化物有差异及遭受后期改造的不同。The Chihu hydrothermal field is the first detachment fault-type hydrothermal field discovered in the southern Mid-Atlantic Ridge by Chinese scientists.The structural characteristics of the Chihu hydrothermal field are different from those of previously discovered detachment fault-type hydrothermal fields.This hydrothermal field is located on the hanging wall of a detachment fault,and two hydrothermal vents have been discovered with the surrounding rock type of basic basalt.This study conducted mineralogical and geochemical analyses of sulfides from the Chihu hydrothermal field by using these methods of ICP-OES,ICP-MS,and LA-ICP-MS.The results showed that the sulfides in the study area can be sub-divided into the following three types:massive,brecciated,and disseminated sulfides.The sulfides in the Chihu hydrothermal field have distinct geochmical differences compared to other detachment fault-type hydrothermal sulfides.The main trace element compositions of bulk rock,trace element contents of pyrite,and sulfur isotope characteristics of sulfides in the hydrothermal field all indicate that the Chihu hydrothermal field may have been influenced by both of basic and ultrabasic rocks.The differences between the two hydrothermal vents in the hydrothermal field indicate that sulfide output from the same hydrothermal system at different periods underwent different later modifications.

关 键 词：南大西洋中脊 赤狐热液区 热液硫化物 拆离断层 硫同位素 

分 类 号：P736[天文地球—海洋地质]