Geofluidodynamic specification for oil and gas mega-reservoirs

The article is devoted to the development of the theoretical foundations of the search for mega-reservoirs of oil and gas in various geological and tectonic settings. The author’s understanding of the term «megareservoir of oil and gas» is formulated as a large-sized reservoir of oil and gas, which has productive intervals brought together within a single oil and gas layer, a large volume of oil and gas saturated space, high fluidity of the geological environment, improved capacitive-filtration properties, hydrodynamic connectivity (or overlapping) accumulation zones and centers of oil and gas generation, geofluid dynamic heterogeneity of the geological environment. The contribution of the multi-scale organization of the uvosphere and underground hydrosphere to the formation of the properties of megareservoirs as oil and gas localizing objects is considered. Differences in the geofluid dynamic mechanisms for filling reservoirs under conditions of hydrodynamically (quasi)open and (quasi)closed systems are substantiated. Keywords: oil and gas mega-reservoirs; geofluid-dynamic heterogeneity; oil and gas bearing stage; hydrocarbon system; reservoir pressures.