Summary Applying geochemical techniques to complex of geological exploration opens wide opportunities for controlling the field development and operation. For example, molecular studies make it possible to understand complex oil reservoirs, find vertical and lateral connectivity, trace oil migration, determine the proportions of commingled production from multiple zones. This paper presents an example of geochemical monitoring of oil from the wells of the Caspian Sea water area. Geochemical survey were based on study of molecular composition of paraffins in gasoline fractions of oil. The molecular composition of oil samples obtained from different wells in period from 2016 to 2020 has been compared. The possibility of identification whether hydrocarbon fluid belonged to the working formation is shown.

Summary Today Bazhenov formation is one of the most challenging and high-potential objects for geological research and oil exploitation. It is unconventional reservoir with low permeability and number of individual alternations with different degree of oil saturation. Determination of perspective intervals is posibble with the use of complex geochemical analysis. The report presents example of oil accumulation zone ranking in Bazhenov formation sediments of well by geochemical data. Alternations segregation is clearly traced in different value of geochemical parameters. This can be helpful for core-oil correlation and fracture growth control after hydrofracturing.

Summary The use of oil-based mud (OBM) in exploration and production drilling has a number of significant advantages. High stability of characteristics over a wide range of temperatures and pressures allows drilling in complicated mining and geological conditions. However, the high affinity of OBM with reservoir hydrocarbons interferes with laboratory studies of core material and fluid samples. Incorrect interpretation of research results leads to incorrect determination of oil saturation intervals, type of fluid, organic matter transformation degree, etc. The report presents some possibilities of geochemical methods for minimizing the influence of technogenic OBM components on the analysis results.

The use of both cellulose and polyurethane rubbers of the PU-8TB and PU-8A grades is discussed in the work to create film materials for draining oils. By the method of IR spectroscopy, the chemical interaction between the hydroxyl groups of cellulose and the carboxyl groups of polyurethane rubber is confirmed. Peculiarities of the thermal properties of the films are studied, which make it possible to speak of the repeated regeneration of materials from absorbed moisture without their destruction. The synthesized film materials have increased elasticity, hydrophilicity, and oleophobicity in comparison with the original cellulose film, which allows them to be used as sorbents and membranes in the field of oil and gas production. The research results showed that polyurethane rubbers PU-8TB and PU-8A, when combined with cellulose, act as functional additives in the manufacture of films capable of removing water from oils.