The results of original scientific investigation for the study of present-day “fracture” ways of the hydrocarbon migration within the Russian sector of the North-Western part of the Caspian sea are considered. The space connections between in the rocks internal structure (the presence of pervious micro-fracturing), in the oil-saturating of rocks, in the presence and quantitative content of rare gases (helium, hydrogen) in the composition of the reservoir fluids selected from search-prospect wells is established at the point level. The criteria for forecasting of the fault-fracture systems of young age (pervious for fluids) and of degree of activity within their present-day fluid-migration processes were the presence or absence of helium and hydrogen (having deep origin and specific physicochemical features of paramount importance for the present study) in the composition of formation fluids (oil, released gas, free gas). The differently oriented fault-fracture systems of young age within the North-Western part of the Caspian Sea are differentiated in the direction and activity degree of present-day migration processes within their limits. So, within the vertical and inclined fault systems (especially in the Southern and Eastern parts of the Russian sector of the North-West Caspian), present-day fluid-migration processes are developing very quickly. The fluids from wells crossing these faults contain helium and hydrogen throughout the section. But, within the horizontal multi-tiered fault-fracture system, regionally developed in the Middle Jurassic-Lower Cretaceous section, present-day fluid-migration processes are developing not so quickly. The helium is present in formation fluids from these fractured intervals, but the hydrogen is absent. The possibility of the forecast of the present-day hydrocarbon migration “fracture” ways on the point (well) level even at the oil and gas search-prospect stage is given.
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