An integrated approach to the study of Achimov deposits within the South Tambey field (Western Siberia)

Abstract

In order to clarify the structure of promising oil and gas objects in the South Tambey field (Western Siberia), an integrated approach to the study of Achimov deposits has been developed. The oil and gas potential level includes layers from PK1 to Yu9 at depths from 1000 to 4000 meters. Despite the fifty-year history of drilling wells in the area, the Achimov objects are currently poorly explored in the study area and may have significant potential for development. The purpose of this work was to clarify the geological structure of the Achimov deposits, which became possible thanks to the acquisition of new geological exploration data during the study of the underlying Jurassic complex. CDP 3D seismic exploration work was completed using a modern full-azimuth observation system, and active drilling of exploration wells for Jurassic deposits in the slope parts of the main structures began. The objectives of the study were the interpretation of a 3D seismic cube covering most of the area of the site, seismic geological linking of data from the Achimov interval of the field with neighboring areas, including using the sequence stratigraphy method, accounting for the results of drilling wells for the pilot development of the Jurassic complex and the transit fund of prospecting and exploration wells, as well as the inclusion of the results of a petrophysical model in a first approximation for the Achimov reservoir interval of the South Tambey field. The results of full-azimuth CDP 3D seismic surveys made it possible to obtain reliable correlations between well data and seismic data, including analysis of AVO attributes (Amplitude Variation with Offset). Based on sequence stratigraphic analysis, the stratification of the section was clarified, correlation with neighboring territories was made, and a conceptual model of the clinoform complex was created. For each layer, system tracts within the sequences were determined. There is strong relationship existing between the formation conditions, geometry of objects and reservoir properties.