Abstract

In February 2020, geochemical tracers along with hydrochemical and hydrological characteristics were used to reveal a discharge site of salt groundwaters in the head of the Razdol’naya R. estuary at a distance of 22 km from its mouth bar. The elevated activity of ²²⁴Ra isotopes from 11.1 ± 0.1 to 2.2 ± 0.05 Bq/m³ in the bottom water layer over a distance of 15 km indicates to the propagation of slightly saline waters from a pool 8 m in depth toward the receiving basin. The distribution of stable water isotopes (δ¹⁸O and δD) and ions of basic salt composition showed that water of the top aquifer at the site of discharge area can suffer the effect of seawater. The major cause of the observed phenomenon is supposed to be the penetration of seawater into the top aquifer within the estuary during winter low-water season and the seepage of this water in the region with largest depth. The contrast of the temperature of ground and surface water was accompanied by a positive temperature anomaly in the zone of their interaction and a decrease in ice thickness along the mixing zone.

中文翻译：

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2020年2月在Razdol'naya河（阿穆尔湾）河口排放盐地下水

摘要

2020年2月，地球化学示踪剂及其水化学和水文特征被用于揭示Razdol'naya R.河口头部距其盐坝22公里处的盐分地下水排放点。在15 km的距离内，底部水层中²²⁴ Ra同位素的活度从11.1±0.1升高到2.2±0.05 Bq / m ³，这表明微咸水从深度8 m的池向接收盆地的扩散。稳定的水同位素的分布（δ ¹⁸O和δD）以及碱性盐组成的离子表明，出水区位置的顶含水层中的水会受到海水的影响。据推测，造成这种现象的主要原因是冬季低水期期间海水渗透到河口内的最高含水层中，并且该水在最大深度的区域渗漏。地下水和地表水温度的反差伴随着它们相互作用区域的正温度异常和沿着混合区域冰厚度的减小。