Elemental Composition of Bottom Sediments and Permafrost Deposits from Buor-Khaya Bay (Laptev Sea)

Abstract

The paper summarizes data on the lithological and elemental composition of bottom sediments and permafrost from boreholes 1D-14, 3D-14, and 1D-15 drilled from shore ice in Buor-Khaya Bay in 2014–2015. Based on the determined percentage content of SiO₂, Al₂O₃, Fe₂O₃, TiO₂, MgO, Na₂O, K₂O, CaO, MnO, P₂O₅, Cl, Cr, S, Ni, Cu, Zn, Rb, Sr, Ba, Y, Zr, and C_org in sediments, the values of lithochemical moduli were calculated, and a comparative analysis of the lithological and geochemical composition was performed. Differences in the lithochemical composition between the coastal (1D-14 and 3D-14) and relatively distant (1D-15) strata were shown, explained by the spatiotemporal variability of sedimentary fluxes and the weathering crust activity in the studied area of the Laptev Sea. Based on the geological structure, the obtained data on the lithochemical composition of thawed and permafrost deposits indicated that sedimentary rocks in the Kharaulakh Ridge of the Verkhoyansk mountain system, corresponding to sandstones, siltstones, and mudstones, were probably the basis of the petrofund. The contribution of igneous and metamorphic rocks to the supply of sedimentary matter in the strata uncovered by drilling was insignificant and of a subordinate nature.