The paper reviews the results of the analysis of textural features in productive sediments of the Pashian horizon in Kitayamskoye field. One of the main problems considered in this paper is a findings of structural reservoirs features which are the compacted terrigenous deposits on the studied area. The sandstone reservoirs are studied as a part of routine laboratory analysis of core and thin sections including lithological descriptions and special methods such as CT scanning and SEM. The findings proved post-diagenetic deformations of the rock fabric. Detailed lithological and petrographic characterization of the target formation revealed the presence of slaty foliation in the sandstones in the zones of maximum compaction with intense concentration of stylolites. It is shown that such zones are associated with well developed fracture networks. The described peculiarities of the productive sandstones of the Kitayamskoye deposit show that rock compaction at the post-diagenetic metamorphism stage have decreased the reservoir properties of productive sandstones of the Pashian horizon. We have suggested that the rock compaction was developed inhomogeneous in the studied section. There are the homogeneous compacted zones as well as the zones of the maximum compaction (places where stylolite seams are frequent). We have studied many bore core samples by different methods including lithology, petrophysics, SEM, X-ray tomography and inferred that the fractured reservoir type takes place in the local places together with an ordinary pore reservoir type.
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