The Wettability of Formation Rocks U1-1 Vasyugan Series

An indicator of the wettability of formation rocks U1-1 Vasyugan Suite (hydrophilicity and hydrophobicity) depends on the reservoir characteristics and composition of oil deposits. Oil fields are characterized as paraffin-naphthene and contain hydrocarbons: naphthenic-27 wt.% (Deposit 1, M1), 61 wt.% (M2); paraffin - 72 wt.% (M1), 22 wt.% (M2.) The increase in the paraffin content in the fluid (M1) creates the conditions of high water-repellency of the rock. M1 rocks have a porosity coefficient of 14-16, the prevailing pore sizes are 0.69-1.69 and 1.62-3.90 mu m, which determines the sorption of paraffinic hydrocarbons. An indicator of the wettability of rocks has a value of 0.20-0.35, the wettability is defined as "predominantly hydrophobic". The smaller characteristic pore size M2 - porosity 12-13.5%, 1.62-of 3.90 mu m, and prevents water-repellency of the rock. Wettability of rocks M2 is characterized as "predominantly hydrophilic", the index of wettability is 0.62 and 0.75. The wettability index on cracking pressure dependences determining the beginning of fluid displacement are constructed. Hydrophobic rocks M1 are characterized by lower values of shear pressure-0.195 kgf/cm(2), for hydrophilic rocks M2 it is - 0.571 kgf/cm(2). (C) 2018 "OilGasScientificResearchProject" Institute. All rights reserved.