Record of hydrothermal activity in the Yuhuang hydrothermal field and its implications for the Southwest Indian Ridge:evidence from sulfide chronology  

作　　者：Weifang Yang Chunhui Tao Shili Liao Jin Liang Wei Li Teng Ding Ágata Alveirinho Dias Xuefeng Wang Lisheng Wang 

机构地区：[1]Key Laboratory of Submarine Geosciences,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China [2]School of Oceanography,Shanghai Jiaotong University,Shanghai 200030,China [3]School of Marine Science and Engineering,Nanjing Normal University,Nanjing 210023,China [4]Institute of Science and Environment,University of Saint Joseph,Macao 999078,China [5]Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

出　　处：《Acta Oceanologica Sinica》2023年第11期59-68,共10页海洋学报（英文版）

基　　金：The National Key R&D Program of China under contract No.2022YFE0140200;the National Natural Science Foundation of China under contract Nos 42127807 and 42006074;the China Ocean Mineral Resources R&D Association Project under contract Nos DY135-S1-1-02 and DY135-S1-1-01;the Macao Science and Technology Development Fund under contract No.FDCT-002/2018/A1。

摘　　要：The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.

关 键 词：Southwest Indian Ridge seafloor massive sulfides 230Th/U dating hydrothermal activity mass accumulation 

分 类 号：P736[天文地球—海洋地质]