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Tectonically quiet upward fluid migration occurs in minor scale due to ascending movements of dilational "clouds" of re-opened fracture network. It caused by wave-like overfalls of the stress in the vicinity of deep faults and represents propagation of local fronts of dilation along them. Even for inactive cratonic areas small periodic variations of the stress field caused by opening-closing cycles for micro-fissures and cracks have been established using seismic waves velocity monitoring. During the stages of relative tectonic rest an activity of that tectonic "pump" transfers water, gases, and hydrocarbons as well by portions from level to level and corresponds to the stage of permanent so-called "cold" outgassing through the basement, being a matter of different-long orders of stress fluctuations. Another situation is typical for mobile belts owing to their active seismogenic environment. According to proposed by R. Sibson (1994) "suction-pump" model to dilational jogs and bends evolution along propagating ruptures, the earthquake slip can provoke (by breaching of impermeable barriers) and realize suction of deep fluids from fluid-saturated crust and transfer them due to fault-valve activity.
It might be supposed that mass discharge of fluids from the deep quasi-stable temporal depots saturated with hydrocarbons is a result of seismogenic implosive collapse of interlinked fractures producing cumulative-like streams towards the surface. Injection of juvenile oil and gas into the sedimentary cover does not necessarily imply that a stable pool will appear in the first reservoir above the crystalline basement. In fact, the dynamics of their injection shows a complexity so pools are usually formed in reservoir compartments of higher porosity and permeability stipulating the best fluid capacitance to perform. That is why the lowermost pools with higher initial pressure in a multistage field may not preserved and can outflow to stationary pools as long as free area of the conduit exists. So the field as such is a result of non-linear redistribution between reservoirs, and absence (or traces) of hydrocarbon pools near the basement/sediments interface is not a paradox, but the exception proving the rule. Being a potent dissolvent, oil (and gas condensate) extracts high-molecular organic matter on its vertical (chimneys) and lateral pathways during secondary and tertiary migration and even able to contain (depending on the density) even fossil pollen and micro-particles of reservoir's matrix. It can effectively capture and incorporate wide spectrum fragmental relics from dispersed organic matter from all host rocks being traced. No surprise, that the shorter distance between a hydrocarbon field and the so-called source rocks in the base of sedimentary column the closer correlation between "biomarkers" is. Recent discovery of deep biota of thermophyllic bacteria allow biological contamination to impact juvenile petroleum even in the crystalline basement.
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