Relationship between the chemical and isotopic composition of natural waters and the newest tectonic structure in the area of Lake Glubokoe (Moscow region)

Relevance. The tectonic factor affects the hydrogeological conditions. To assess the tectonics impact on hydrogeological conditions, it is necessary to use an integrated approach. The article considers the hydrogeochemical features of groundwater formed in the area of Lake Glubokoe in the Moscow region, confined to the so-called Trostenskaya depression. Aim. To identify the isotope-chemical characteristics of groundwater due to the effect of the latest tectonic structure of the area. Methods. The chemical composition of natural waters was monitored using ion chromatography on a high-performance ion liquid chromatograph LC-20 and inductively coupled plasma mass spectrometry on an Agilent 7700 x spectrometer. The contents of stable isotopes of oxygen (δ17O and δ18O) and hydrogen (δD) were determined by laser light attenuation spectroscopy with an annular multi-pass cuvette on a Picarro L2140i analyzer. Results and conclusions. The groundwater of the Podolsk-Myachkovsky aquifer complex in the area of development of the Trostenskaya depression is characterized by increased mineralization, as well as a higher content of bicarbonates and calcium, compared to groundwater common in the peripheral parts of the research area. Higher concentrations of micro-components (strontium, barium, scandium, rubidium, etc.) were recorded within the studied structure. Groundwater characterized by a heavier isotopic composition (δ18O, δD, δ17O) is also confined to the Trostenskaya depression. Data on the ratio of δ18O, δ2H and δ17O in natural waters were obtained for the first time for the studied area. It is likely that groundwater in the central and northwestern parts of the study area has a heavier formed isotopic composition due to the inflow of water in the postglacial period.