Advanced wells are being used more and more frequently to improve the economics of oil field operations. Such wells can contact larger regions of the reservoir than is possible with standard wells. Because these wells can be very long, pressure drop along the well and temperature effects (in thermal problems) can became quite important. Modeling of advanced wells where thermal effects need to be included is a difficult task, and available models are often limited in their capabilities or are inefficient.A suitable model should be able to handle complicated well trajectories, heat transfer to and from the well, the hold-up of fluids due to slip between phases, and pressure change due to friction. This paper presents a comprehensive multisegmented well model that includes these features. The model has been implemented in Stanford's General Purpose Research Simulator (GPRS). It calculates both pressure and temperature profiles along the well for standard wells and wells with complicated trajectories. One of the advantages of our model is that both homogeneous (no slip) and drift-flux flow models can be used to determine phase distribution within the well. The hydrocarbon fluids can be described either through a black oil representation or using a general compositional model with an arbitrary number of components. The proposed multisegmented well model was tested with a number of challenging and realistic examples. Our results show that the model is stable and in most cases converges in only a few iterations even with reasonably large time steps. The capabilities of the model are demonstrated using three examples. The first example involves a vertical production well with the fluid represented in terms of six hydrocarbon components and water. For this case we demonstrate the importance of slip between phases. The second example is for a thermal multilateral well with two branches and a fluid with three hydrocarbon components. The third example shows our ability to model phase appearance and disappearance in the wellbore and demonstrates the impact of temperature on oil and gas rates during production.Significant effort has been directed towards the modelling of thermal wells, starting from analytical models proposed by, e.g., Ramey (1962) and Hasan and Kabir (2002), to complicated numerical models, such as those proposed by Shirdel andSepehrnoori (2009) andStone et al. (2002). All available models have advantages and disadvantages: some cannot model pressure loss due to friction, slip between phases or complicated well trajectories; some are not accurate or fast enough, and some are too complicated for routine use. The multisegmented well model proposed here allows the calculation of temperature, pressure, in-situ phase fractions, and component fraction profiles for realistic well geometries, such as multilateral, deviated and horizontal wells. Our model is available in black oil (Jiang, 2007 andLivescu et al., 2010) and compositional formulations (preliminary compositional results 1 Now with ExxonMobil

Salinity is one of the most important factors that primarily determines the level of seawater’s density and, consequently, the movement of water masses in the World Ocean. Spatial distribution of the salinity in different layers of the Black Sea are associated with varying levels of water balance seasonal variability and, general circulation of Black Seas waters and in the surface layer has a seasonal structure. To study spatial distribution of salinity in upper layers of the Black Sea we’ve used data from Copernicus Marine Environment Monitoring Service, that were processed and aggregate by seasons and depth. We found that the most fluctuated layer is a top layer (up to 2.8 m) and the highest values Black Sea salinity reaches near the Bosporus Strait, where more saline water from the Sea of Marmara connected with fresher water of the Black Sea. Also we found that the impact of the river flows, mixing of the water, water regime of the sea decreasing with depth, so in the bottom of the upper layer the spatial fluctuation of the salinity is minimal and reaches about ±3‰, while in the depth of 2.8 m its reaches ±12-15‰.The lowest level of salinity through all of the upper layer (0-50 m) lays around the seashore and north-western part of the sea.

Climatic changes that have occurred over the past decades, with an acceleration of urbanization of territories and technological development, leads to the significant changes not only in the atmosphere, but also in the Earth’s surface. Surface water bodies are one of these components. Today there are 3 main methods of monitoring water bodies -field, remote and combined. In this paper, we show the possibility of automating remote monitoring of water bodies using QGIS, Python and Sentinel-2 data of the main and largest lakes of the Kerch Peninsula. Having analysed both the available satellite data and the features of the study area, we came to the conclusion that it is advisable to use the NDWI index instead of the mNDWI. After processing and analysing the Sentinel-2 data for 2018 using the data processing model presented in the work, we obtained time series of changes in the areas of the studied lakes of the Kerch Peninsula.

Sea water temperature and water salinity one of the most important environmental factors of the marine ecosystems. Both of them plays an important role in forming suitable environment for marine living organisms and have a great impact on species biodiversity. Our goal for this paper was to identify spatial patterns of interannual variations in the salinity and temperature fluctuations to understand possibilities of future change of the Black Sea ecosystem and its impact on fisheries. We used temperature and salinity data from CMEMS for the 1992-2017 time period. All downloaded data was processed by QGIS 3.14 and R 4.0.3. We found that the temperature regime of the Black Sea in different periods of the year is determined by three main factors - the depth of the shelf zone, the influence of river runoff, and water circulation due to currents. The average salinity of the Black Sea waters is 19 ‰, areas with lower salinity are located near the west shore, due to the flows from the largest rivers (Dnieper, Dniester, Danube) bringing a large amount of fresh water to the Black Sea. The area with higher salinity is located in the south- west due to the water exchange of the Black Sea with the saltier Sea of Marmara (∼ 26 ‰) through the Bosphorus. The currents of the Black Sea pick up the salty water of the Sea of Marmara and slowly moving the water column against the clockwise, carry it across the entire Black Sea, thereby increasing its average salinity.

As a result of a study of the Pravdinsk reservoir, it was found that the radiation situ ation can be estimated as safe. According to microbiological indicators, the water quality was assessed as polluted with β, α-mesosaprobic, 3-4 classes of water quality. During the "bloom" of water by Cyanobacteria, we observed the toxic effect on the test organisms Daphnia magna and Ceriodaphnia affinis, in this period the consumption of phytoplankton by zooplankton was low. According to benthos biomass, the reservoir is assessed as a water body with a high food value. The ichthyofauna included 14 species of fish that belonged to families of Cyprinidae, Percidae, Gadidae and Esocidae. 11 species of parasites related to Microsporidia, Myxosporidia, Trematoda, Cestoda, Hirudinea and parasitic Crustacea were found. Metatercaria of trematoda Apophallus müehlingi pathogenic for humans were found in roach and perch.