Particle-Size Analysis of Modern Bottom Sediments by the Laser Diffraction and Sieve Methods.

A combination of laser diffraction and wet sieving through a nylon screen with a 0.1-mm mesh has been suggested for the particle-size analysis of silty bottom sediments from estuarine and coastal sea areas. The necessity of individual determination of sand fractions even in case of the technical ability of the device to analyze the content of coarse particles to 2 mm in size is shown. This is related to poor sorting of coastal silts and inadequately represented weighed samples used for the standard laser diffraction particle-size analysis. In addition to sand fractions, the pre-sieving affects the determination of the 0.1–0.01 mm silt fractions, while its impact on the analysis of pelite fractions of less than 0.01 mm is minimal. The effectiveness of the proposed modified method is proved by the closer correlation between the content of pelite fractions and the concentration of metals and organic carbon in bottom sediments. [ABSTRACT FROM AUTHOR]