泉州湾表层沉积物粒度分形特征与沉积学关系研究

Study on the fractal characteristics of grain size and the relationship among sedimentology of surface sediments in the Quanzhou Bay

为了进一步揭示泉州湾表层沉积物粒度结构特征,本文在所有样品统一的无标度区间、相关系数大于0.90的前提下,进行了粒度分形维数的计算,同时结合沉积物粒度参数、沉积物类型、地球化学、黏土矿物指标等进行相关性分析。结果表明:(1)分维值是沉积物粒度结构特点的综合反映,能够有效指示沉积物特征;(2)较粗的砂质沉积物分维值大多低于2,不具有良好分形结构,而较细的沉积物类型中,平均粒径越小、分选性越好、粒级频率曲线越不对称、越平缓,分维值越高;(3)砂、黏土质粉砂、砂质粉砂、粉砂质砂、砂-粉砂-黏土,平均分维值依次呈现增高趋势;(4)分维值和大多地球化学元素没有明显相关性,和黏土矿物有较弱的相关性。粒度分维值在综合判别沉积环境具有一定的推广价值。

In order to further reveal the characteristics of the grain size structure of the surface sediments in the Quanzhou Bay,this paper carried out the calculation of the grain size fractal dimension under the premise that all samples have a uniform scale-free interval and the correlation coefficient is greater than 0.90.Correlations are analyzed combined with the sediment grain size parameters and sediment types,geochemistry,and clay mineral indicators.The results show that:1)The fractal dimension is a comprehensive reflection of the characteristics of the grain size structure of the sediment,which can effectively indicate the characteristics of the sediment;2)The fractal dimension of the coarser sandy sediments is mostly lower than 2,which does not have a good fractal structure.Among the fine sediment types,the smaller the mean grain size,the better the sortability,the more asymmetrical and gentler the size frequency curve,the higher the fractal dimension;3)The average fractal dimension value shows an increasing trend in sand,clayey silt,sandy silt,silty sand and sand-silt-clay in turn;4)The fractal dimension value has no obvious correlation with most geochemical elements,and has a weak correlation with clay minerals.The value of grain size fractal dimension has a certain promotion value in comprehensively distinguishing the sedimentary environment.