西南极南设得兰群岛地层对比与划分  

Stratigraphic correlation and division of the South Shetland Islands,west Antarctica

作　　者：韦利杰[1,2,3] 陈虹 赵越[1,2,4] 刘晓春 胡健民[1,2,4] WEI Lijie;CHEN Hong;ZHAO Yue;LIU Xiaochun;HU Jianmin(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;Research Center of Polar Geosciences,China Geological Survey,Beijing 100081,China;Key Laboratory of Neotectonic Movement and Geohazard,Ministry of Natural Resources,Beijing 100081,China;Key Laboratory of Paleomagnetism and Tectonic Reconstruction,Ministry of Natural Resources,Beijing 100081,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]中国地质调查局极地地学研究中心,北京100081 [3]自然资源部新构造运动与地质灾害重点实验室,北京100081 [4]自然资源部古地磁与古构造重建重点实验室,北京100081

出　　处：《地质通报》2022年第2期347-360,共14页Geological Bulletin of China

基　　金：国家自然科学基金重点项目《冈瓦纳古陆最后裂解在西南极的地质记录及其环境意义》(批准号:41930218);中国地质调查局项目《特殊地质地貌区填图试点》(编号:DD20160060);中国-智利国际合作项目《中智合作南设得兰群岛125万地质填图》。

摘　　要：对南设得兰群岛基岩区进行地质调查和研究,恢复其地层层序与演化过程。通过野外考察和资料收集,对比分析了前人年代学、地球化学、古地磁学、古生物学、地层学等方面的研究成果,将南设得兰群岛地层划分为24个岩石地层单元,建立了南设得兰群岛中—新生代火山-沉积地层层序和年代学格架。研究表明;南设得兰群岛火山活动早白垩世—早中新世总体呈现从西南向东北迁移的趋势,可能是被断裂分割的洋底从西南向西北先后发生俯冲的结果;第四纪以来,伴随布兰斯菲尔德海峡的打开,在裂谷环境中,形成了以幔源碱玄武岩浆喷发的迪塞普申岛、企鹅岛等。研究结果为深化研究南设得兰群岛的构造演化和古环境重建提供依据。Through the geological investigations and studies of the bedrock in the South Shetland Islands,the stratigraphic sequence and evolution process were restored.Based on fieldworks and data collection,previous results of geochronology,geochemistry,paleomagnetism and paleobiology,the volcanic-sedimentary strata in the area were divided into 24 stratigraphic units,and the stratigraphic framework of the Mesozoic-Cenozoic volcanic-sedimentary rocks in the South Shetland Islands was constructed.The results show that the volcanic activity in the South Shetland Islands generally migrated from southwest to northeast from early Cretaceous to early Miocene,which might be the result of the subduction of the ocean floor divided by faults from southwest to northwest.Since the Quaternary,with the opening of Bransfield Strait,Deception Island and Penguin Island have been formed with alkali basaltic magma of mantle source in the rift environment.The result provides a basis for the further study of the tectonic evolution and the paleoenvironmental reconstruction of the South Shetland Islands.

关 键 词：西南极 南设得兰群岛 中—新生代 火山-沉积地层 地质调查工程 

分 类 号：P53[天文地球—古生物学与地层学] P58[天文地球—地质学]