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Recently abundant material evidencing for the polygenesis of oil and gas has been piled. Any processes in the evolution of oil and gas is subordinated to global processes in the energy, dynamics, and degassing of the Earth.
Geophysical surveys carried out at the depth of 10-25 km established anomalies featuring inversions of seismic velocities, changes in rock electric conductivity, and other phenomena. These anomalous zones of fractured rocks filled with fluids were described as crustal waveguides (CWs). A mechanism involving dilatancy and compaction in CWs was found out. Dilatancy refers to fracture opening and filling CWs with fluids, including abyssal hydrocarbons. In compaction, the fluids are more or less pressed out of CWs. They move towards lesser pressures, into upper levels of the Earth's crust, and intensely 'wash' sedimentary rock sequences. These processes cater for efficient collection of microoil into pools. A deposit evolves, and while accumulating oil and gas of organic origin, it can pull in abyssal hydrocarbons.
In interaction between the energy fields, the Earth's potential is realized under different conditions. That brings about accumulation of energy in the Earth and evolvement of energetically active zones where mineral hydrocarbon synthesis occurs. Further energy concentration brings the fluid system in an extremely non-equilibrium state. Instability of the system causes bifurcation and outbursts of energy and matter. These conditions promote the development of fault zones and channels over which abyssal fluids, including hydrocarbon fluids, are intensely transported, and their further accumulations evolve in magmatic and metamorphic sedimentary rocks.
As to the evolvement of the White Tiger field, a polygenic hypothesis was offered to explain how transformation of the organic matter was activated by the impact of strong thermal flux from the granite intrusion penetrating into the sedimentary mantle. While an intrusive body is cooling, and contraction is underway, underpressure cavities and diversely oriented fractures are formed in the upper zones. Thermosetting creates a pressure drop, and that pulls the microoil from the overlying sedimentary rocks into the perimeter of the cooling intrusive. The intense fluid dynamics brings about the development of an extra holding capacity within the entire volume of the granite intrusive and accumulation of abyssal hydrocarbon fluids within its boundaries. The impact of abyssal fluids leads to voids, cavities, and fractures; on top of that, it causes some cardinal changes in the granitoid structure, generating a loose, unconsolidated substrate. Well flow rates in such zones are in excess of 2.0 TT per day. The most intensely transformed rocks within the northern vault, producing the highest oil influxes, are within the depth range of 4200?4700 m. It is worthwhile to underscore that there are weakly altered crystalline rocks above.
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