Conditions for the Interaction of Marine and Fresh Waters in the System of Coastal Flooded Quarries in the Southeastern Baltic

Abstract

The western coast of the Kaliningrad region (Russia) is known for its amber quarries. While one quarry is active, others, the Yantarny Pond and a chain of beach coastal quarries, have been flooded by the waters of subsurface horizons. This article explores objective factors behind seawater intrusion and infiltration into the flooded quarries through aquifers, which connect them to the coastal parts of the sea. Changes in the geomorphology and morphometry of the catchment surface due to quarrying were traced by analyzing the cartographic data and satellite images. The obtained results show a reduction in the size of the catchment area, shifts in the hydrological network, and the emergence of new water bodies. Three aquifers provide subsurface feed to the water bodies and discharge into the sea. They are also connected with the existing quarry and the water supply system of the Yantarny municipality. Hydrological field data reveal higher mineralization of the Yantarny Pond waters compared to other freshwater bodies in the study area, as well as a local near-bottom anomaly of highly mineralized waters. The water level of the flooded beach quarries is currently above sea level, but they have different salinities, indicating their transitional state from fresh- to seawater bodies.