Features of substantiation of calculation parameters of hydrocarbon deposits, confined to new stratigraphic objects, in conditions of limited data and absence of direct geological analogues (on the example of the Khayan-Kort field)

UDK: 553.98

DOI: 10.24887/0028-2448-2025-5-74-78

Key words: deposit, hydrocarbons, reservoir, well logging (WL), well testing (WT), petrophysical model, Lower Maykop, analogue, exploration, monitoring, development

Authors: A.A. Brailovskaya (NK Rosneft-NTC LLC, RF, Krasnodar); A.S. Gudkov (NK Rosneft-NTC LLC, RF, Krasnodar); I.A. Zemtsova (NK Rosneft-NTC LLC, RF, Krasnodar); V.M. Yatsenko (Rosneft Oil Company, RF, Moscow)

Most of the Ciscaucasia oil fields are in the final stage of development or have been completely developed. The reduction in the fund of economically viable production facilities predetermines the need to increase the efficiency of additional development and exploration of fields. The search for missed hydrocarbon deposits is currently relevant for this region. For the first time in more than 20 years, employees of PJSC NK Rosneft and its subsidiaries Rosneft-NTC LLC and Grozneftegaz JSC have discovered and brought into production two oil deposits in a new stratigraphic range  the Lower Maykop deposits. The non-target status of the Maykop deposits, combined with extremely difficult drilling conditions and a significant amount of lost data within the Terek-Caspian trough, predetermined its low geological and geophysical exploration. This, along with the absence of reliable analogous deposits in the Eastern Ciscaucasia, led to the need to apply a non-standard integrated approach to interpretation of petrophysical well logging model and assessing the calculation parameters within the framework of calculating hydrocarbon reserves. The solution of the problems is based on the creation of a data matrix with characteristics for the Maykop deposits of the North Caucasian oil and gas region, their ranking by the degree of compliance of the parameters and maximum relevance of the geological parameters of the reserves calculation object. This, along with the involvement of additional information, enabled to calibrate the well logging interpretation technique, substantiate the adopted boundary values, and establish objective probabilities of the range of their change.

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