北冰洋欧亚大陆边缘表层沉积物全岩轻矿物组成及其环境指示意义  

Surface sediment bulk mineralogical composition and environmental implica-tions in the Eurasian Continental Margin,Arctic Ocean

作　　者：张伟滨 赵嵩 刘焱光 ZHANG Weibin;ZHAO Song;LIU Yanguang(College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China;First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China;College of Ocean Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]中国海洋大学,环境科学与工程学院,山东青岛266100 [2]自然资源部第一海洋研究所,山东青岛266061 [3]山东科技大学,海洋科学与工程学院,山东青岛266590

出　　处：《极地研究》2024年第3期406-420,共15页Chinese Journal of Polar Research

基　　金：国家自然科学基金(42176245);重点研发计划(2023YFF0804601)资助。

摘　　要：北冰洋欧亚大陆边缘是海冰的主要生成区域,由洋流、海冰和冰山输送的陆源碎屑沉积物是北冰洋沉积物的主要组成部分,沉积物中矿物组成是揭示北冰洋物质来源、洋流模式的重要资料。本文基于前人应用X射线衍射法研究的441个北冰洋欧亚大陆边缘全岩轻矿物组成资料,探索研究区全岩轻矿物来源及搬运分选模式。研究结果表明:(1)北冰洋欧亚大陆边缘的轻矿物以石英和长石为主,石英具有多个特征源区并广泛分布于研究区各处;(2)长石族主要包括斜长石和钾长石,表征了典型的火山物质输入,是发育火成岩省和火山带的欧亚北极大陆特征矿物。斜长石通常由北极河流输送入海,并通过海冰搬运到更远的地区,因此其分布与穿极流的路径极其相似;(3)钾长石对应冰山搬运的粗颗粒物质,其高值分布在欧亚大陆边缘,与斜长石的解耦表明了其对区分不同的火山来源物质具有一定的意义;(4)白云石通常来自于北美源区,方解石来源则更复杂,可能包含了自生来源。以上研究结果有助于更全面理解北冰洋沉积物源-汇过程,为厘清北冰洋欧亚大陆边缘沉积环境变化提供重要参考。The Eurasian Continental Margin of the Arctic Ocean is the main area of sea ice formation.The terri-genous clastic sediments transformed by ocean currents,sea ice and icebergs are the main components of sediments in the Arctic Ocean.The mineral composition is a significant proxy to reveal the provenance of materials and ocean current patterns in the Arctic Ocean.Based on the complied data of 441 bulk mineral samples from the Eurasian Continental Margin of the Arctic Ocean studied by previous reports using X-ray diffraction,this paper explores the source and transportation and sorting patterns of bulk minerals in the study area.The results show that:(1)The light minerals in the Eurasian Continental Margin of the Arctic Ocean are mainly quartz and feldspar.Quartz has multiple characteristic sources and is widely distributed throughout the study area;(2)The feldspar group mainly includes plagioclase and K-feldspar,which repre-sent typical volcanic material input and are characteristic minerals of the Eurasian Arctic continent with de-veloped igneous provinces and volcanic belts.Plagioclase is usually transported into the sea by Arctic rivers and to further regions by sea ice,so its distribution is extremely similar to the path of the Trans Polar Drift;(3)K-feldspar corresponds to coarse-grained material carried by icebergs,and its high distribution at the margin of the Eurasian continent and its decoupling from plagioclase in several regions indicate that it has a certain significance in distinguishing different volcanic sources;(4)Dolomite usually comes from the North American source area,while the source of calcite is more complex and may include authigenic sources.The above research results help to more fully understand the source-sink process of Arctic Ocean sediments and provide an important reference for clarifying the changes in the sedimentary environment at the margin of the Eurasian Continental Margin,Arctic Ocean.

关 键 词：表层沉积物 全岩轻矿物 物质来源 北冰洋欧亚大陆边缘 

分 类 号：P736.41[天文地球—海洋地质]