2015年3月在中国北方呼伦湖采集100 cm湖泊沉积物岩芯并进行粒度分析,揭示了呼伦湖岩芯粒度参数的垂向分布序列。研究区柱状沉积物粒度组成以18 cm、60 cm和86 cm 为界限分4个主要的阶段,并且小于16μm组分含量和大于32 μm组分含量基本呈反向变化趋势,中值粒径的变化趋势和砂质组分含量的变化趋势一致。通过粒径-标准偏差法,获得了呼伦湖沉积物岩芯中对沉积时期环境变化较为敏感粒度组分范围约为大于30 μm。利用主成分分析法,得到两个主控因子F1和F2,它们贡献了湖泊沉积物近88.12%的粒度变化特征。这两种方法相互结合,可以有效的探讨呼伦湖沉积物沉积时的古气候(降水,季风等)信息,同时其它一些环境要素也有较好地体现。
英文摘要:
A 100cm length of sediment core was taken from Hulun Lake of China in March, 2015. The grain size analysis was carried out and the vertical distribution series of the grain size composition profile was determined. There are 4 main stages with 18cm, 60cm and 86cm as divisions. The variations of the grain size composition that was<16μm and>32μm were in opposite directions, and the composition variations of the median grain size and sandy were similar. The environmentally sensitive grain size composition of the sediment core of Hulun Lake was larger than 30μm determined by particle size standard deviation method. Two main controlling factors F1 and F2 were obtained by the principal component analysis method, which accounted 88.12% of the variation of the grain size characteristics. By combining the two methods, the information of the paleoclimate (precipitation, monsoon, etc) could be effectively investigated, and the other environmental factors could also be indicated.