Abstract

A study of the chemical composition of pore waters of bottom sediments in the northeastern part of the Barents Sea is presented. It has been established that the salinity of silt waters is formed mainly due to Cl^–, Na⁺ ions, and, to a lesser extent, sulfate ions and Mg²⁺. In terms of composition, the pore water is classified as sodium chloride and is close to the composition of the surface water of the Barents Sea. For the first time, experimental data on the capacity of cation exchange (13.98–35.50 μg/100 g of rock) and the composition of the exchange complex of deposits (Na > Mg > Ca > K) are presented. According to the classification of V.A. Sulina, 90% of the investigated samples of pore water have a marine origin. There is a change in the type of water to chloride–sodium–calcium due to cation exchange processes in bottom silts. An extremely weak manifestation of sulfate reduction processes in some samples and their absence in the overwhelming majority of bottom sediment samples were found. It is shown that one feature of pore waters is a weak course of processes of their direct metamorphisation. It was found that the concentration of dissolved rare earth elements (REE) in pore water is up to 1.589 μg/L with their content in the silt up to 144.051 mg/kg; negative cerium and positive europium anomalies are observed both in the pore water and in bottom sediments. According to the saturation index calculations for all samples, undersaturation of pore water concerning the content of gypsum and halite and supersaturation in some samples in calcite and dolomite were revealed, indicating the possibility of the formation of the latter in sediments during diagenesis. Comprehensive interpretation of the results made it possible to obtain a complete understanding of the leading geochemical processes of the formation of the chemical appearance of silt waters in the pore water–bottom sediments system in the northeastern part of the Barents Sea.

中文翻译：

---

巴伦支海东北壳底部沉积物多孔水的地球化学

摘要

介绍了巴伦支海东北部底部沉积物孔隙水化学成分的研究。已经确定，淤泥水的盐度主要是由 Cl ^-、 Na ⁺离子形成的，其次是硫酸根离子和 Mg ²⁺. 就成分而言，孔隙水被归类为氯化钠，与巴伦支海地表水的成分接近。首次展示了阳离子交换能力（13.98-35.50 μg/100 g 岩石）和矿床交换络合物组成（Na > Mg > Ca > K）的实验数据。根据 VA Sulina 的分类，90% 的研究孔隙水样本来自海洋。由于底部淤泥中的阳离子交换过程，水的类型变为氯化物-钠-钙。发现在一些样品中硫酸盐还原过程的表现极其微弱，而在绝大多数底部沉积物样品中它们不存在。结果表明，孔隙水的一个特征是其直接变质过程的过程较弱。孔隙水中溶解性稀土元素（REE）浓度高达1.589 μg/L，淤泥中稀土元素含量高达144.051 mg/kg；在孔隙水和底部沉积物中均观察到铈的负异常和铕的正异常。根据对所有样品的饱和指数计算，揭示了与石膏和岩盐含量有关的孔隙水欠饱和以及方解石和白云石中的一些样品过饱和，表明在成岩过程中沉积物中形成后者的可能性。通过对结果的综合解释，可以全面了解巴伦支海东北部孔隙水-底沉积体系中淤泥水化学表象形成的主导地球化学过程。