珠江口内伶仃洋海域近百年来沉积物粒度变化和重金属分布特征

发布时间：2018-05-31 23:41

本文选题：重金属 + 粒度　；参考：《海洋地质与第四纪地质》2016年01期

【摘要】：对珠江口内伶仃洋不同海域3个柱状样沉积物进行的210 Pb测年和重金属分布特征垂向变化分析;研究了近百年来珠江口沉积速率时空变化;探讨了在自然作用和人类活动影响下重金属分布特点和累积因素。结果表明,珠江口内伶仃洋海域东西两岸的沉积物平均粒径4~7.5Φ,横门和深圳海域沉积物敏感组分呈现出显著双峰分布,粗细组分分界线为5.25Φ,淇澳岛沉积物敏感组分不明显,沉积环境较为稳定。基于210Pb测年的CIC模式,获得了各个岩心的现代沉积速率,横门海域沉积速率1.6cm/a,淇澳岛海域沉积速率4.08cm/a,0~70cm深度内深圳西海岸海域沉积速率2.58cm/a,70cm以深沉积速率为4.47cm/a。重金属含量分析表明,Cr、Ni、Cu、Zn和Pb含量从1923—1986年维持较高水平,但是变化不大;1967—1983年的深圳海域和1983—2004年的淇澳岛海域,各重金属元素含量快速上升;进入2000年以后,2003—2005年和2008—2012年,重金属含量呈现逐年减小趋势,2005—2008年则表现为逐年上升;这些变化与沿岸的社会经济发展、重金属入海量紧密相关。
[Abstract]:The 210 Pb dating of 3 columnar sediments in the different waters of the Pearl River Estuary and the vertical variation of the distribution characteristics of heavy metals in the Pearl River Estuary were analyzed. The temporal and spatial changes in the deposition rate of the Pearl River Estuary were studied in the last hundred years, and the distribution and accumulation of heavy metals under the influence of natural and human activities were discussed. The results showed that the Pearl River Estuary was in the estuary of the Pearl River Estuary. The average grain size 4~7.5 diameter of the sediments on both sides of the East and west regions is 4~7.5. The sensitive components of the sediments in the cross gate and the Shenzhen sea area show a significant Shuangfeng distribution, the boundary of the coarse and fine components is 5.25. The sediment sensitive components of Qiao island are not obvious, and the sedimentary environment is more stable. Based on the CIC model of 210Pb dating, the modern sedimentation rate of each core is obtained, and the cross gate sea area is obtained. Sedimentation rate is 1.6cm/a, the sedimentation rate of Qiao island sea area is 4.08cm/a, the sedimentation rate of Shenzhen west coast is 2.58cm/a in the depth of 0~70cm. 70cm with the deep deposition rate of 4.47cm/a. heavy metal content analysis shows that the content of Cr, Ni, Cu, Zn and Pb maintains a high level from 1923 to 1986, but the change is not great; Shenzhen sea area of 1967 - 1983 and 1983 - 2004 The content of heavy metals in the waters of Qiao island rose rapidly. After 2000, from 2003 to 2005 and from 2008 to 2012, the content of heavy metals showed a decreasing trend year by year, and from 2005 to 2008, the content of heavy metals increased year by year. These changes were closely related to the social and economic development along the coast and the amount of heavy metals into the sea.
【作者单位】：国土资源部海底矿产资源重点实验室中国地质调查局广州海洋地质调查局;海岸与海岛开发教育部重点实验室南京大学地理与海洋科学学院;
【基金】：国土资源部海底矿产资源重点实验室开放基金(基金号:KLMMR-2014-A-08) 中国地质调查局地质调查项目(GZH20120202)
【分类号】：P736.4;X55

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