Oil Potential of Sargaevskian Horizon in Romashkinskoe Field Areas

High extent of subsurface exploration activities in the Republic of Tatarstan results in ever increasing scarcity of hydrocarbon resources available for the purposes of oil production. Under such conditions, the search for and development of overlooked reservoirs within existing producing fields become of great importance. The Sargaevskian horizon is associated with unique Domanic deposits which are considered the main oil source rocks within the Volga-Ural petroleum province. Domanic rocks are capable of both generating and accumulating hydrocarbons. This paper analyses all available G&G data from previous studies of the Sargaevskian sediments in Almetyevskaya and Aznakaevskaya areas of Romashkinskoe field. Reinterpretation of open-hole logs run in 712 wells was conducted to refine the geological structure and evaluate the oil potential. Data acquired using modern logging methods including pulsed neutron logging and pulsed neutron spectroscopy gamma-logging were used to identify potential reservoir zones and evaluate fluid saturation in cased holes. Saraylinskoe field located within the same facies zone as Romashkinkoe field and having the confirmed oil potential of Sargaevskian horizon was reviewed. 

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