Orenburg Oblast, Russia. North Eastern slope of Zhiguli-Orenburg Arch. Lower carboniferous deposits.
Exploration task; depth of investigation: 1950-2000 m
LFS investigations covered a previously identified field confined to two structures. At the start of works, some prior information was available on three wells (Nos. 314, 315 and 317) within the structures with the presence of oil in the lower carboniferous sediments and on further three wells (Nos. 310, 316 and 322) outside the structures with no oil bearing in the section.
Based on the results of the work, the central part of the Eastern structure was characterized as not promising whilst the Western structure was almost completely covered by the oil-promising area according to the LFS data.
The position of wells Nos. 1-5, 8, 14, 16 and the results of the testing were obtained after the work was completed.
By testing wells Nos. 1-5, 8, 16, commercial oil inflows from the lower carboniferous sediments were obtained, although well No. 14 fell through the marks and the deposits of the Lower Carboniferous were aquiferous.
The subsequentd LFS investigation of well No. 14 showed a decrease in the marks towards the central part of the eastern structure and its disintegration into two domes.
The correlation maps presented in the lower part of the slide show the spectra from the reference dry and oil wells and spectra of the study area. Red indicates a high correlation coefficient between the spectra.