青岛近岸泥质区敏感粒级组分及对沉积记录的指示  

SENSITIVE GRAIN SIZE OF THE MUD DEPOSITS OFFSHORE QINGDAO AND ITS IMPLICATIONS FOR SEDIMENTARY ENVIRONMENTS

作　　者：宋红瑛[1,2,3] 刘金庆[2,3] 马晓红[1,2,3] 张勇[2,3] 赵广涛 

机构地区：[1]中国海洋大学海洋地球科学学院,青岛266100 [2]国土资源部油气资源和环境地质重点实验室,中国地质调查局青岛海洋地质研究所,青岛266071 [3]青岛海洋科学与技术国家实验室海洋矿产资源评价与探测技术功能实验室,青岛266071

出　　处：《海洋地质与第四纪地质》2016年第6期51-61,共11页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目(41376079);1:25万青岛幅海洋区域地质调查(试点)(GZH200900501)

摘　　要：通过对青岛南部近岸泥质区3个岩心（Z14、Z16、QDZ03）进行粒度分析和AMS14 C年龄测试,研究了沉积物粒度组成并提取了敏感粒级,探讨了敏感粒级的搬运机制及其环境指示意义。研究表明：研究区岩心沉积物以粉砂和黏土质粉砂为主,包含3个敏感粒级（敏感粒级1、敏感粒级2、敏感粒级3）,分别对应粒度细端组分、中端组分和粗端组分,以悬浮和跳跃搬运为主,少量以滚动、推移方式搬运;沉积物主要受沿岸流输运的影响,粒度组分自东北向西南逐渐变细,反映了水动力条件自东北向西南逐渐减弱的趋势;其中,敏感粒级2对东亚冬季风增强事件具有较好的反映：利用QDZ03孔上部3.94m岩心沉积物敏感粒级获得了近3ka以来5个明显的东亚冬季风增强事件（230~370、1 050~1 180、1 400~1 550、1 850~1 950和2 250~2 350aBP）,对古气候记录具有较好的指示作用。Three cores（Z14,Z16 and QDZ03）retrieved from the Qingdao offshore mud area were analyzed for grain size distribution and AMS 14 C dating in order to study the grain size distribution pattern and their sensitive components for revealing of the transporting mechanism and their environmental implications.The sediments in the three cores are mostly composed of silt and clayey silt.Observed are three sensitive grain sizes,i.e.the sensitive grain size 1,the sensitive grain size 2and the sensitive grain size 3,respectively corresponding to the components of the fine end,medium-grained and coarse end in the particle size distribution.The sediment mainly consists of suspended load and saltation load,with a little bed load.It is mainly transported by the nearshore currents and the particle sizes are gradually getting smaller from northeast to southwest.It means that the hydrodynamics is gradually weakened from northeast to southwest.Among the three,the sensitive grain size 2represents the record of the enhanced winter monsoon event.The sensitive grain size（15.63-210μm）in the upper part（0-3.94m）of the Core QDZ03 reveals that there are five enhanced events of East Asian Winter Monsoon（230-370 aBP,1050-1180 aBP,1400-1550 a BP,1850-1950 aBP and 2250-2350aBP）over the past 3ka.The case proves that the sensitive grain size could be used as a good indicator of paleoclimate records.

关 键 词：敏感粒级 粒径趋势分析 东亚冬季风 青岛近岸泥质区 

分 类 号：P376.3[天文地球—地球物理学]