The work performed on the basis of the integrated interpretation of seismic survey, geophysical well logging, test results and petrophysical studies is devoted to the gas presence of the Aptian-Albian-Cenomanian sediments in the Arctic regions of Western Siberia and on the shelf of the Kara Sea. Fields of the Nadym-Pur, Yamal, Gydan and South-Kara petroleum regions (PR) of the Western Siberian petroleum province are considered as reference objects. Seismic and geological criteria for the gas presence prediction of the Senomanian and Aptian-Albian reservoirs are formulated based on the results of the research. It is shown that massive Cenomanian gas accumulations are imaged in wave seismic fields by: 1) the presence of reflective horizons forming on gas-water contacts at reflection-time sections and the decline in the amplitude characteristics of the G reflecting horizon, confined to the Cenomanian top; 2) the increase in the values of the time thickness, reduction in the interval velocities and decrease in the amplitude-energy characteristics of the seismic dataset in the Aptian-Cenomanian megacomplex. The Aptian-Albian sheet gas accumulations are displayed at reflection-time sections by a sharp increase in the amplitudes of the seismic record, forming the ˝bright spot˝ anomalies in the wave fields.

Keywords: Western Siberia, Kara Sea, reflection-time section, seismic sequence, depositional sequence, reflecting horizon, seismic anomaly, ˝bright spot˝.

DOI 10.20403/2078-0575-2018-4-41-48