Pore waters geochemistry of bottom sediments in the northeastern part of the Barents sea

Abstract

The paper presents the pore waters composition’s experimental results in the northeastern part of the Barents Sea. The pore water contains Cl–, Na+, SO4 2– and Mg2+ as dominant components and is quite similar to the Barents Seawater composition. For the first time, we measured the cation exchange capacity of (13.98-35.50 meq/100 g) and the exchanging cations composition (Na+>Mg2+>Ca2+>K+) of bottom sediments. We find that most of the sampled pore water (near 90%) have marine nature, and only near 10% is slightly transformed with sulfate reduction processes due to the diagenesis. We measure that the rare earth elements (REE) content in pore water is up to 1.589 μg/L with their content in sediments up to 144.051 mg/kg, negative cerium and positive europium anomalies are observed both in the pore waters and in bottom sediments. We calculated using PHREEQC that pore water undersaturated to gypsum and halite and supersaturated to calcite and dolomite, which may precipitate in deposits during diagenesis.