Geochemical characteristics and their geological implication in sediments from Laizhou Bay since late Quaternary

Element geochemical information is important for stratigraphic division and provenance analysis. The characteristics of major and trace elements in the sediments of core BH1302 in Laizhou Bay are analyzed, whose concentrations change obviously at the stratigraphic boundary and can be used as an important index for the classification of late Quaternary strata. Combined with the lithologic facies, grain size and dates of core BH1302, the sediments in the study area since the late Quaternary can be divided into four phases, which corresponding to late Middle Pleistocene, MIS 5, MIS 4—3 and MIS 1, respectively. In vertical, the changes of major and trace elements of the core are characterized by a symbiotic relationship. Except for Na₂O、Ba and Sr, most of the major and trace elements are strongly correlated with the mean particle size in the vertical distribution. R-type factor analysis revealed that the supply of terrigenous fine and coarse particulate and marine authigenic elements had important effects on the geochemical composition, but the effects are different in different periods. Terrigenous fine particulate supply is the dominant factor, but terrigenous coarse particulate supply or marine authigenic elements supply may also be the dominant factor in a short period.