Geologiczne warunki występowania węglowodorów w poziomie wapienia cechsztyńskiego Werry we wschodniej części syneklizy perybałtyckiej
Abstract
GEOLOGICAL CONDITIONS OF HYDROCARBON ACCUMULATION IN THE HORIZON OF BASAL ZECHSTEIN LIMESTONES IN EASTERN PART OF THE PERIBALTIC SYNECLIZE
Summary
The paper deals with the lithological characteristics and hydrocarbon aocumulation capacity of Zechstein, Werra series limestones form the Peribaltic syneclize. The features of these limestones indicating their ability to accumulate hydrocarbons are as follows: - The zone of increased thickness of Zechstein, Werra series, limestones has a form of bank continuing paralleIy to the Mazury-Suwałki elevation, that facilitates formation of lithostratigraphical ore enclosures. - The carbonates of the Lower Zechstein age are characterized by high collector indices in this zone. - The carbonate deposits of the Lower Zechstein age are overlain by anhydrites and salts of rock sealing characteristics. - The zone of increased thickness of Lower Zechstein carbonate deposits corresponds to the area of Prepermian outcrops of the Ordovician and Lower Cambrian, which might have facilitated impregnation of Zechstein carbonate series with hydrocarbons in result of possible lateral eastward migration. - The zones of tectonic looseness might have facilitated the vertical migration of hydrocarbons from Lower Paleozoic deposits. – The results of geochemical studies have shown a possibility of Postzechstein bitumen migration within the older PaIeozoic series and of their accumulation in younger deposits, provided the structural conditions were suitable. - The hydrochemical studies have shown a remarkable degree of metamorphism of Zechstein salt brines as well as other advantageous indices of water chemistry. - Macroscopic traces of bitumens are known from the horizon of Zechstein basal limestones from the Peribaltic syneclize area. - In other parts of Poland, a number of earth-gas accumulations were found in places where Zechstein basal limestones and Lower Permian (Rotliegend) deposits are overlying older series with erosional discontinuity.
Summary
The paper deals with the lithological characteristics and hydrocarbon aocumulation capacity of Zechstein, Werra series limestones form the Peribaltic syneclize. The features of these limestones indicating their ability to accumulate hydrocarbons are as follows: - The zone of increased thickness of Zechstein, Werra series, limestones has a form of bank continuing paralleIy to the Mazury-Suwałki elevation, that facilitates formation of lithostratigraphical ore enclosures. - The carbonates of the Lower Zechstein age are characterized by high collector indices in this zone. - The carbonate deposits of the Lower Zechstein age are overlain by anhydrites and salts of rock sealing characteristics. - The zone of increased thickness of Lower Zechstein carbonate deposits corresponds to the area of Prepermian outcrops of the Ordovician and Lower Cambrian, which might have facilitated impregnation of Zechstein carbonate series with hydrocarbons in result of possible lateral eastward migration. - The zones of tectonic looseness might have facilitated the vertical migration of hydrocarbons from Lower Paleozoic deposits. – The results of geochemical studies have shown a possibility of Postzechstein bitumen migration within the older PaIeozoic series and of their accumulation in younger deposits, provided the structural conditions were suitable. - The hydrochemical studies have shown a remarkable degree of metamorphism of Zechstein salt brines as well as other advantageous indices of water chemistry. - Macroscopic traces of bitumens are known from the horizon of Zechstein basal limestones from the Peribaltic syneclize area. - In other parts of Poland, a number of earth-gas accumulations were found in places where Zechstein basal limestones and Lower Permian (Rotliegend) deposits are overlying older series with erosional discontinuity.