Petroleum processes in the Palaeozoic-Mesozoic strata of the Grobla-Limanowa area (basement of the Polish Carpathians).
Magdalena Wróbel, Paweł Kosakowski, Dariusz Więcław
Vol. 42, 2 (2016), s. 185-206
The geochemical characteristics of the Palaeozoic and Mesozoic strata of the basement of the Carpathian Foredeep depicted the Devonian and Carboniferous source rocks as the best source for hydrocarbon generation. Moreover, the Outer Carpathian sequence was geochemically characterized and proved capable of generating hydrocarbons. The oil-source rocks’ correlations indicated that the source of the condensate accumulated in the Łąkta field, while oil in the Grobla field. Maturity modelling identified Devonian source rocks as they reached a late phase of the “oil window” and, locally, even the “gas window”. The Carboniferous source rock was mature enough to start the generation processes. The generation started in the late Carboniferous, both in the Upper Silesian and Małopolska blocks. The main phase of the petroleum processes took place in late Neogene. The expulsion was observed only in the Devonian source rocks, and vertical migration by fault system in both blocks resulted in oil and gas accumulation in the Upper Jurassic carbonates and Upper Cretaceous sandstones. The petroleum modelling indicated the Devonian source for oil and gas fields in the study area. However oil-source rock correlation also suggests the presence of the Carpathian flysch source for hydrocarbons accumulated in the Łąkta field.