广东东海岛大岭剖面风沙沉积序列及化学特征分析  

Sedimentary sequence and geochemical characteristics of aeolian sands in the Daling section of Donghai island,Guangdong

作　　者：叶怡欣 黄日辉 冯淼彦 唐道斌 李巧云 陈绮雯 李思琦 杨志通 李健禧 YE Yixin;HUANG Rihui;FENG Miaoyan;TANG Daobin;LI Qiaoyun;CHEN Qiwen;LI Siqi;YANG Zhitong;LI Jianxi(School of Geographical Sciences,Lingnan Normal University,Zhanjiang 524048,China;School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,China)

机构地区：[1]岭南师范学院地理科学学院,广东湛江524048 [2]中国地质大学地球科学学院,湖北武汉430074 [3]西北师范大学地理与环境学院,甘肃兰州730070

出　　处：《海洋湖沼通报》2023年第4期48-54,共7页Transactions of Oceanology and Limnology

基　　金：岭南师范学院人才引进专项项目(1170918278);湛江市海洋青年人才项目(2021E05023)。

摘　　要：利用广东省东海岛大岭剖面海岸风沙沉积元素地球化学分析,结合14C测年结果,探讨了大岭剖面采样部分的沉积序列、地球化学特征以及环境意义。结果表明:(1)常量元素组成主要为SiO_(2)、Al_(2)O_(3)和Fe_(2)O_(3)三种;(2)活跃元素相对全球上陆壳含量有所减少,相对稳定元素Al、Fe的含量往上呈现减少趋势;(3)化学蚀变指数(CIA)反映了剖面形成时处于中等风化程度,化学风化三角图(A-CN-K图)样品点的分布集中紧凑,体现气候条件较为稳定;(4)大岭剖面(⑨—①层)所反映的气候环境整体向干凉方向发展,期间划分两个阶段:第一阶段,表现为暖湿环境,其中含有一个温度湿度有所减少的时期;第二阶段,相比上阶段温度湿度都有所减少,海岸风沙活动加强。In this paper,the sedimentary sequences,geochemical characteristics of aeolian sands in the Daling section of Donghai island,Guangdong province,and their indicative climate change were investigated using elemental geochemical analysis in conjunction with radiocarbon dating.The results show that:(1)The compositions of macroelements were mainly SiO_(2),Al_(2)O_(3)and Fe_(2)O_(3).(2)The content of active elements had decreased relative to the global upper crust,and the content of relatively stable elements Al and Fe decreased with decreasing depth.(3)The chemical index of alteration reflected the moderate weathering level at that time,and A-CN-K diagram showed that the distribution of sample points was concentrated,reflecting the stable climatic conditions.(4)The climate environment reflected by the Daling section(discussed herein)showed an overall development towards dryness and coolness,during which there were two stages.The first stage showed a warm and humid environment,which contained a period of decreasing temperature and humidity.The second stage showed a decrease in both temperature and humidity compared with the previous phase and an increase in sand drift activities.

关 键 词：化学特征 沉积序列 海岸风沙 古环境 东海岛 

分 类 号：P595[天文地球—地球化学] P532[天文地球—地质学]