Assessment of Caprock Fluid-Resistive Characteristics of Pre-Urals Fore Deep Southern Part

One of the main reasons for failure during the exploration for oil and gas is poor properties of caprocks. The analysis of models of generation and accumulation of hydrocarbon-systems (GAHC), including all necessary elements (source rock, reservoirs, impermeable layers, overburden rocks) and processes (generation, migration and accumulation of hydrocarbons and the formation of traps) for the formation of hydrocarbon deposits in the sedimentary basin allows to minimize the risks associated with the unreliability of caprocks and thus with the security of deposits of hydrocarbons (HC).

In order to the reliability assessment of caprocks and degree of deposits preservation within the Orenburg part of the Pre-Urals fore deep and by using the PetroMod software (Schlumberger) the geological model of the area of research was formed and studies of the distribution of capillary pressure in time was conducted for four generation-accumulative hydrocarbon systems, corresponding to the four oil and gas complexes (OGC): Lower Devonian, Frasnian, Frasnian--Tournaisian, Visean-Bashkir and Lower Permian