Geological factors in the formation conditions of traps in the Orchyk depression perm deposits of Dnieper-Donets basin

Abstract

A variety of screens has been examined theoretically, their screening and limiting functions in hydrocarbon traps formation have been demonstrated. Among their variety as main ones we regard covering and bottom fluid-proof rocks, disjunctives, salt-bodies, hydrodynamic pressure, etc. Place of screens development and their crucial (screening) and secondary (limiting) functions in trap generation were observed. Screen role in deposits and oil and gas field trap forming of Orchik depression uplifts (Upper Carboniferous and Lower Permian rocks apart) were specified. Significant difference in trap types of the series was demonstrated. Leaving out singular exclusion, non-arch lithologic, disjunctive and salt-dome screened and limited traps are most typical for Lower Permian rocks, while Carboniferous traps are mostly screened and limited quasiarch.

The research results, based on virtual data of field studies in detal, are evidence of all the types of screens in the research territory’s wide spreading. Their trap generating and trap limiting role makes it possible to define traps and fields type. Essential part of traps is non-arch.

Variety of traps are caused by screens of different types which act as separate factors, could form complex with others and can be reliable basis for prognosis of similar conditions. Such conditions can exist not only on uplifts but also on monoclines, near-salt-stocks zones and synclines.