Stream-scanning laser system, electric sensing counter and settling grain size analysis: a comparison using reference materials and grain marine sediments

Surface and deep-sea core sediments and two sets of standards were measured by three different techniques - Galai Cis-1 laser system, Coulter Counter TA II, and Micromeritics SediGraph 5000D - in order to compare the Galai re sults with the other two. The differences between the three types of measur ing device turned out to be greater in sediments than in standards, and wer e attributed to the physical properties, shape, density and composition of the particles (complexity of the matrix). Comparison of moment statistics s howed that the Galai determines coarser grain sizes than the Coulter and fi ner than the SediGraph, particularly as regards analysis of surface sedimen ts. The relationships between Galai and SediGraph were estimated using anal ysis of variation/residuals within individual intervals. The analysis showe d a higher variability of residuals for the coarser fractions (8-16 mu m an d 16-32 mu m) with respect to the finer (2-4 mu m and 4-8 mu m) fractions, The <2 mu m SediGraph fraction, with a cut-off at 0.49 mu m, showed good co rrespondence with the <2.5 mu m Galai analysis. (C) 2000 Elsevier Science B .V. All rights reserved.