Factors controlling regional spatial distribution of 53 elements in coastal sea sediments in northern Japan: Comparison of geochemical data derived from stream and marine sediments

摘要: Abstract In all, 53 elements were analyzed in 1406 coastal sea sediment samples collected from an area off Hokkaido and the Tohoku region of Japan during a nationwide marine geochemical mapping project. The spatial distribution patterns elemental concentrations seas along with existing maps terrestrial areas used to define natural background variation mass transport processes. is covered by mafic volcanic rocks accretionary complexes associated ophiolite, which has small amounts felsic granite. enriched lithologies such as Fe (Total 2 O 3 ) Sc environments are influenced adjoining materials. Cr Ni concentrations, highly abundant ultramafic on land, evaluate land dispersive processes caused oceanic currents. scale currents occurs up distance 100–200 km coast areas. regional differences rich K (K O), Nb La sediments determined mainly relative proportion minerals lithic fragments enriching materials those concentration not always continuous between That difference interpreted resulting (1) transportation storm waves, (2) contribution tephra, (3) occurrence shell foraminifera tests (4) relict last glacial age early transgression age. Contamination Cu, Zn, Cd, As, Mo, Sn, Sb, Hg, Pb Bi was observed because study little anthropogenic activity. Terrestrial dominant source for these metals. silty clayey locally diagenetic processes, authigenic precipitation organic substances elements. As shows exceptions: it concentrated some coarse fine sands shelf. enrichment explained adsorption sourced coal field, hydroxide.