Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 52357 10.2205/2022ES000776 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Morphological and chemical features of submarine groundwater discharge zones in the south-eastern part of the Baltic Sea Morphological and chemical features of submarine groundwater discharge zones in the south-eastern part of the Baltic Sea Крек Александр В Krek Alexander V Данченков Александр Р Danchenkov Alexander R Михневич Галина Сергеевна Mikhnevich Galina Sergeevna Институт океанологии им. П.П. Ширшова РАН Москва Россия Shirshov Institute of Oceanology RAS Moscow Russian Federation Институт океанологии им. П.П. Ширшова РАН Moscow Россия Shirshov Institute of Oceanology RAS Moscow Russian Federation Балтийский федеральный университет имени Иммануила Канта Калининград Россия Immanuel Kant Baltic Federal University Kalilingrad Russian Federation 26 09 2022 26 09 2022 22 4 1 12 26 08 2021 06 09 2021 https://rjes.ru/en/nauka/article/52357/view

The complex study of the bottom sediments and near-bottom water layer of the Gdansk Deep revealed the Ca maximum anomaly, marking the discharge of the Oxford-Titonian aquifer. The discharge zone is associated with gas-saturated sediments, which is caused by a common pathway of aqueous and gaseous fluids upraise along tectonic faults. The detailed survey of a seabed topography and acoustic survey of the sediments upper layer helped to specify the area of gas-saturated sediments and the size of the pockmarks.

The complex study of the bottom sediments and near-bottom water layer of the Gdansk Deep revealed the Ca maximum anomaly, marking the discharge of the Oxford-Titonian aquifer. The discharge zone is associated with gas-saturated sediments, which is caused by a common pathway of aqueous and gaseous fluids upraise along tectonic faults. The detailed survey of a seabed topography and acoustic survey of the sediments upper layer helped to specify the area of gas-saturated sediments and the size of the pockmarks.

 Submarine groundwater discharge pockmark Gdansk Deep ground water bottom sediments Submarine groundwater discharge pockmark Gdansk Deep ground water bottom sediments The hydrochemistry part of the research was supported by RFBR and the Kaliningrad region government (\# 19-45-390007 r\_a "Influence of submarine groundwater discharge on the formation of bottom sediments in the Gdansk basin of the Baltic Sea". The hydrophysical and geoacoustical study was done with a support of the state assignment of IO RAS (FMWE-2021-0012). The hydrochemistry part of the research was supported by RFBR and the Kaliningrad region government (\# 19-45-390007 r\_a "Influence of submarine groundwater discharge on the formation of bottom sediments in the Gdansk basin of the Baltic Sea". The hydrophysical and geoacoustical study was done with a support of the state assignment of IO RAS (FMWE-2021-0012).

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