德雷克海峡打开与构造古海洋古气候演变  

The interaction between the opening of the Drake Passage and global paleoceanographic-paleoclimatic change

作　　者：张梦薇 高亮[1,2] 赵越 裴军令[3] 杨振宇 郭晓倩 胡新炜[1,2] ZHANG Mengwei;GAO Liang;ZHAO Yue;PEI Junling;YANG Zhenyu;GUO Xiaoqian;HU Xinwei(Key Laboratory of Polar Geology and Marine Mineral Resources(China University of Geosciences,Beijing),Ministry of Education,Beijing 100083,China;School of Ocean Sciences,China University of Geosciences(Beijing),Beijing 100083,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China;College of Resources,Environment and Tourism,Capital Normal University,Beijing 100048,China)

机构地区：[1]中国地质大学(北京)极地地质与海洋矿产教育部重点实验室,北京100083 [2]中国地质大学(北京)海洋学院,北京100083 [3]东华理工大学核资源与环境国家重点实验室,江西南昌330013 [4]首都师范大学资源环境与旅游学院,北京100048

出　　处：《地学前缘》2024年第6期415-435,共21页Earth Science Frontiers

基　　金：国家自然科学基金项目(41930218,42322607,42076223);中央高校基本科研业务费专项(265QZ2021013)。

摘　　要：德雷克海峡的打开受到南美南部和南极半岛北部板块运动与构造演化影响,并导致南极绕极流和现今大洋环流模式最终形成,是理解新生代全球变化的关键因素之一。前人通过古大陆重建与古海洋学相关方法研究德雷克海峡打开与南极绕极流形成过程,本文总结了前人研究成果,并综合南极半岛北部与南美南部新生代构造演化和全球大洋底栖有孔虫δ^(18) O、δ^(13) C、全球深海溶解氧含量、大气CO_(2)浓度、全球大洋生产力变化等数据,提出40~35、30~25和20~18 Ma 3期德雷克海峡打开与南极绕极流加强的关键阶段。这3期事件发生于南极半岛北部与南美南部的关键构造演化阶段,其中后两个阶段发生在大西洋经向翻转流形成之后,对应全球大洋底栖有孔虫δ^(13) C低值、大气CO_(2)浓度低值、深海溶解氧低值、南大洋高生产力和赤道海区低生产力阶段。据此,我们提出南极半岛北部与南美南部相关构造事件导致南极绕极流增强,并主导了这些时期的古海洋与古气候变化,这一认识有助于厘清德雷克海峡演化的重要阶段及其对全球变化的影响。The opening of the Drake Passage has been influenced by the tectonic movements and evolutionary processes of the southern part of South America and the northern part of the Antarctic Peninsula,leading to the eventual formation of the Antarctic Circumpolar Current and today’s ocean circulation pattern,which is one of the key factors for understanding global changes during the Cenozoic era.Previous studies have investigated the opening of the Drake Passage and the formation of the Antarctic Circumpolar Current through methods related to paleocontinental reconstruction and paleoceanography.This paper summarizes previous research findings and integrates data on the Cenozoic tectonic evolution of the northern Antarctic Peninsula and southern South America,as well asδ^(18) O,δ^(13) C values of global deep-sea benthic foraminifera,global dissolved oxygen content,atmospheric CO_(2)concentrations,and changes in global ocean productivity.It proposes three critical stages of the opening of the Drake Passage and the strengthening of the Antarctic Circumpolar Current occurring around 4035 Ma,3025 Ma,and 2018 Ma.These events happened during key tectonic evolutionary phases of the northern Antarctic Peninsula and southern South America,with the latter two stages occurring after the formation of the Atlantic Meridional Overturning Circulation,corresponding to periods of lowδ^(13) C values in global deep-sea benthic foraminifera,low atmospheric CO_(2)concentrations,low dissolved oxygen levels in the deep sea,high paleoproductivity in the Southern Ocean,and low paleoproductivity in equatorial sea regions.Accordingly,we propose that the tectonic events related to the northern Antarctic Peninsula and southern South America caused the strengthening of the Antarctic Circumpolar Current,which dominated the paleoceanographic and paleoclimatic changes during these periods.This understanding helps clarify the significant stages of the evolution of the Drake Passage and its impact on global changes.

关 键 词：南极半岛北部 南美南部 德雷克海峡 板块构造 古海洋 古气候 

分 类 号：P728[天文地球—海洋科学]