Geology, geography and global energy

Scientific and Technical Journal

Identification of the gas-bearing potential of the T1-X reservoir in the interval of the Tagandzha suite of the Lower Triassic of the Vilyui syneclise (Eastern Siberia) using the Bayesian classification method based on AVO analysis

2022. №3, pp. 50-57

Feoktistova Olga V. - Yakut Fuel and Energy Company JSC, Vilyuyski ulus, Kysyl-Syr village, Russia

Currently, seismic surveys are being actively carried out on the territory of the Khapchagai mega shaft and the adjacent territories of the Vilyui syneclise of the Republic of Sakha (Yakutia), including new territories poorly studied by drilling, seismic exploration and other geophysical methods. In this connection, it is relevant to study the structure of productive intervals according to CDP 3D seismic data in order to search for signs of identifying potentially promising zones on CDP 2D data. Another important task is to search for missed hydrocarbon traps in existing fields. For this purpose, an analysis was carried out to identify the features of the formation of hydrocarbon traps in the lower part of the Tagandzha suite according to regional research data, effective seismic recording attributes and seismic data analysis technologies were identified to identify potentially promising zones according to CDP 3D data in order to apply the experience gained in the future to CDP 2D data, as well as. CDP 3D in conditions of limited drilling data. This article presents the results of the analysis, which made it possible, using the example of one of the fields in Eastern Siberia, to identify the missed potentially promising hydrocarbon traps of the T1-X formation, clarify the zones of facies replacements, determine tectonic screens, and give recommendations for exploration drilling.

Key words: Eastern Siberia, Vilyui syneclise, Khapchagai mega shaft, Triassic, Tagandzha Formation, seismic attributes AVO anomalies, classification, Bayesian networks, missed hydrocarbon traps