БЕЗПЕКОВА СКЛАДОВА ВИВЧЕННЯ РОЗВАНТАЖЕННЯ ГЛИБИННИХ ФЛЮЇДНИХ ПОТОКІВ НА ДНІ ЧОРНОГО МОРЯ

Problem Statement and Purpose. The achievements of geological science together with the forecast of new mineral resources, especially oil and gas in the marine environment, have also revealed natural phenomena that exist on the Black Sea bottom and imply substantial risk. These include (1) methane emissions through seeps and gas plumes that are prone to spontaneous catastrophic combustion and (2) eruptions of mud volcanoes accompanied by the release of breccia and mineralized solutions of deep fluids that change the physical and chemical properties of the seawater. Obviously, these natural phenomena pose a serious threat to the safety of navigation, both for surface and underwater vessels. This paper is aimed at a comprehensive study of the deep fluid flows unloading onto the seabed in order to create a consistent GIS enabling us to determine their locations and differentiate them by degree of danger (weak, medium, strong, and very strong) for any kind of vessel in the economic zone of Ukraine and the adjacent deep-water part of the Black Sea. Data & Methods. The paper is based on materials obtained in the course of marine expeditionary work performed by the Laboratory of Marine Geology, Geochemistry and Micropaleontology of Odessa I. I. Mechnikov National University followed by their processing in 2008-2024 during a number of international (HERMES, WAP-COAST) (Yanko et al., 2014; Yanko et al., 2017; Shnyukov and Yanko-Hombach, 2020) and national projects supported by the Ministry of Education and Science of Ukraine, such as “Methane in the Black Sea” (Yanko-Hombach et al., 2019; Shnyukov and Yanko, 2017; Shnyukov and Yanko-Hombach, 2020), “Development of predictive criteria for search of hydrocarbon deposits in the Black Sea based on the theory of fluidogenesis” (Chepizhko et al., 2020; Chepizhko et al., 2021; Dikol, 2022), and “Study of unloading of deep fluid flows at the bottom of the Black Sea to assess the safety of navigation.” The methods used involved grain-size, mineralogical, chromatographic, X-ray diffractometric, thermobarogeochemical, isotopic (δ13C, δ18O), paleontological, and remote sensing of the Earth. Sentinel-3 satellite images (SLSTR) to study the temperature and other parameters of the sea surface were used (Suchkov et al., 2017; Yanko et al., 2021; Dikol, 2022; Yanko et al., 2024). Results. Natural methane emissions at the Black Sea bottom can affect navigation safety to varying degrees depending on their intensity. The most dangerous are the catastrophic methane emissions associated with mud volcanoes. Most of these are located at great depths, and the frequency of their eruptions is quite low, however, some shallow water mud volcanoes (e.g., Vladimir Parshin) can pose a danger during their eruption. The greatest danger is posed by large eruptions, during which the jet of gas being emitted from the deep Earth, can rise hundreds of meters, sometimes reaching the surface. In this case, the density of water inside the jet, composed of gas bubbles of various sizes, may dramatically change the water density, leading to a loss of vessel buoyancy and foundering. To an even greater extent, such phenomena will affect the navigation of submarines. Taking into account such risks requires a detailed and interactive GIS-aided map of the locations of existing methane emissions. Such a map has been created by us but still needs further improvement, particularly in the search for new methane emissions on the Black Sea bottom that are not as yet documented. For these purposes, we have developed new remote sensing methods based primarily on the interpretation of geological data obtained from space images. It has been shown that thermal spectral images can be very helpful since they contain an endogenous component of recorded events. It is especially important at the present time because no fieldwork can be performed in the Ukrainian part of the Black Sea due to ongoing hostilities.