现代黄河三角洲北岸YRD-1101孔岩心磁性地层学  

STUDIES ON MAGNETOSTRATIGRAPHY OF CORE YRD-1101 SEDIMENTS ON THE NORTH SHORE OF MODERN YELLOW RIVER DELTA

作　　者：孙丽莎[1,2] 刘健[1] 仇建东[1] 李国涛 项立辉[3] 

机构地区：[1]青岛海洋地质研究所,青岛266071 [2]山东第八地质矿产勘查院,日照276826 [3]江苏省有色金属华东地质勘查局,南京210007

出　　处：《海洋地质与第四纪地质》2014年第4期31-40,共10页Marine Geology & Quaternary Geology

基　　金：中国地质调查局地质矿产调查评价专项项目(1212011120172);国家自然科学基金重点项目(41330964)

摘　　要：对渤海南岸黄河三角洲地区200.30m的YRD-1101钻孔进行了系统的岩石磁学和古地磁学研究。岩石磁学研究表明沉积物中主要载磁矿物是碎屑磁铁矿,部分样品含有少量铁硫化物和赤铁矿;古地磁学研究结果揭示了早、中更新世界线即布容（Brunhes）正极性时/松山（Matuyama）负极性时界限（B/M）位于该钻孔123.33m处,同时,发现在松山负极性时记录了不完整的奥尔杜威（Olduvai）正极性亚时（191.78～200.30m）;根据沉积速率推测该孔底部200.30m的年代为1.885Ma。这一研究为该钻孔提供了可靠的年代标尺,为渤海湾南岸黄河三角洲第四系地层的划分和对比提供了新的依据。Studies of magnetostratigraphy and rock magnetism have been conducted for the samples from borehole YRD-1101 that is 200.30 mlong and located on the north shore of Modern Yellow River Delta,south coast of the Bohai Sea.Rock magnetic studies indicate that the main magnetic mineral in the sediments is detrital magnetite,with subordinate iron sulfide and hematite.The Brunhes/Matuyama boundary was found at the core depth of 123.33 m,and one incomplete normal polarity zone corresponding to Olduvi Subchron in 191.78-200.30 m.The basal age of the borehole is estimated at about 1.885 Ma by extrapolation of the sedimentation rate in the Matuyama Chron.Our results provide a reliable chronological framework for the borehole,facilitating the stratigraphic division of the Quaternary strata in the Modern Yellow River Delta.

关 键 词：磁性地层 岩石磁学 第四纪地层 渤海 黄河三角洲 

分 类 号：P736.22[天文地球—海洋地质]