TY JOUR TI Study of Natural Reservoirs in the Volcanogenic-Sedimentary to Pre-Jurassic Complex of the West Siberian Oil-Gas Basin KW volcanics KW method of rocks classification by well LOGs KW reservoir properties KW pre-Jurassic complex KW West Siberian Plate JO Russian Journal of Earth Sciences AU Alekseev, A.D. AU Nemova, V.D. AU Sapogova, E.E. AU Rostovtseva, Y.V. PY 2025 IS 25 PB Geophysical Center of the Russian Academy of Sciences