渤海曹妃甸海域沉积物粒度激光法与综合法测试结果对比

Testing results comparison between laser method and comprehensive method for sediment grain size in Caofeidian of Bohai Sea

激光法与综合法(吸液管法-筛析法)均是测试沉积物粒度特征的常用方法,由于测试原理和流程的差异,这两种方法对同一样品分析所获得测试结果往往不尽一致。为探究两种方法的共同性、差异性和相关性,并建立适合曹妃甸海域激光法与综合法测试结果之间的转换关系,通过对曹妃甸海域49个沉积物样品分别进行激光法和综合法实验,对比结果表明:①激光法与综合法所测砂粒含量大致相等,粉砂含量激光法所测结果高,黏土含量综合法所测结果较高;②激光法和吸液管法测试结果误差主要在发生在10φ(φ=log2 D,D为直径,φ为单位)阶段,吸液管法测将黏土含量显著升高,激光法与筛析法结果误差主要发生在粗端颗粒,激光法测得粗端颗粒含量普遍偏高;③激光法与综合法粒度参数回归分析随着粒径减小相关性逐渐降低,粒度参数回归方程的斜率、截距与前人研究结果不具有统一性。研究建立的曹妃甸海域激光法与综合法数据转换模型分析表明,在粒度范围[-1,4]φ,激光法和综合法所获得数据结果可以进行相互转换;明确了激光法与综合法测量沉积物粒度特征的差异。研究成果对使用激光法测量沉积物粒度特征和完善测试方法与流程有参考意义。

Laser method and comprehensive method(pipette method-sieve method)are commonly used to test the sediment grain size characteristics.Due to the differences in testing principles and analysis processes,the test results obtained by these two methods for the same sample are often not completely consistent.In order to explore the commonalities,differences,and correlations between the two methods,and establish a conversion relationship between the results by laser method and comprehensive method suitable for this sea,the authors in this research compared testing results by these two methods from 49 sediment samples in Caofeidian.The results show that:①Sand content measured by laser method and comprehensive method is roughly equal.And silt content measured by laser method is generally higher than the result by comprehensive method,and the clay content measured by laser method is generally lower than the result by comprehensive method.②The difference between laser method and pipette method mainly occurs at 10φ,and the clay content by comprehensive method significantly increased.The difference between laser method and sieve analysis method mainly occurred in the coarse end grain,and the coarse end grain content is generally higher measured by laser method.③The correlation between laser method and comprehensive method in grain size parameter regression analysis gradually decreases as the grain size decreases.The slope and intercept of the gran size parameter regression equation also do not have a unified conversion relationship with previous research results.It is found that laser method is feasible in measuring the grain size characteristics of sediments,and a data conversion model was established between laser method and comprehensive method in Caofeidian.The data results obtained by these two methods can be converted to each other with a grain size range of[-1,4]φ.The difference of grain size characteristics by laser method and comprehensive method is clarified,which can be used as a reference for the measurement of grain size characteristics of sediments and a improvement of testing methods and procedures.