Features of compaction of sedimentary rocks of oil and gas deposits

Abstract

The process of compaction of sediments determines the patterns of changes in the properties of rocks of oil and gas bearing sections, primarily their porosity. The porosity of rocks of different lithology varies depending on their depth. The study of the regularities of changes in the porosity of rocks is important for the identification of geological sections, for substantiating the intervals of the existence of reservoirs with intergranular porosity type, for forecasting the properties of support layers by section and for methodological support for the geological interpretation of the materials of geophysical studies of wells. The existing concept of gravitational compaction of sediments doesn't reflect a number of features of this process of rocks in real conditions. The article substantiates the conditions of precipitation formation corresponding to their transition to an initial relatively stable state. The features of precipitation formation in the initial marine and continental conditions, as well as the features of their formation in permafrost strata are substantiated.The general patterns and features of the compaction curves of typical sandstones and clays are considered according to the data of reference wells drilled within the West Siberian oil and gas basin.