Source rock

a concept with many uncertainties

has confined the thoughts of explorationists for a long time. V.B.Porfiriev

the late Academician of Ukraine Academy of Sciences

proposed a theory of deep origin of hydrocarbons

i.e. generation of hydrocarbons has been related to activities of the upper mantle. At the end of Tertiary

hydrocarbons migrated vertically upward from the upper mantle along large fracture belts and accumulated in the porous-fractured reservoirs in the basement and sedimentary cover. Deep and ultra-deep drilling in Gulf of Mexico has verified that oil pool can occur in reservoir up to a depth of 6 885 m. It is justified to believe that should fractured zones exist in the deep crystalline and metamorphic rocks below the basin's basement

they would be the petroleum occurrences. Therefore

it would be possible to open up frontiers of petroleum exploration through deep drilling.