Facial-cyclic analysis of deposits of the Talakh horizon in the framework of construction of a geological model of the field in the Eastern part of the Nepsky swell

Aim. In order to make a qualitative prediction of reservoir properties in the inter-well space, a lithological-facies characteristic of deposits of the Talakh horizon was performed and a seismogeological correlation of cyclites was performed within the framework of constructing a three-dimensional geological model.
Materials and methods. As a result of the lithological-facies study of the core, facies were isolated, then combined into macrofacies, of which the main macrofacies of the reservoirs were given a lithological-petrophysical characteristic. Based on the results of facies analysis, data from geophysical well surveys (GIS) and the results of seismic interpretation, two transgressive cyclites were identified, differing from each other in facies composition and petrophysical properties.
Results. On the basis of a complex interpretation of the core and GIS, the facies series of sediments within the Talakh horizon has been reconstructed, the cyclicity of the section is described, which is represented by the lower Tl2 cyclite, composed of more continental deposits of facies of alluvial and tidal channels, with an increased reservoir content and an increased porosity value relative to the upper Tl1 cyclite, which is represented by more marine deposits mainly of delta facies of tidal-low tide type.
Conclusions. As a result of the conducted studies, a detailed lithological and facies characteristic of the section within the Talakh horizon on the territory of the study area was obtained. The information obtained helped to clarify the geological structure of the object and more correctly predict the properties of the reservoir, using its own lithology and porosity trends separately for each cyclite.

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