Geochemiczne przesłanki ciągłości złoża gazu i ropy naftowej w rejonie Barnówko-Lubiszyn wynikające ze składu węglowodorów ciekłych w dolomicie głównym
Abstract
GEOCHEMICAL INDICATIONS OF CONTINUITY OIL AND GAS BASIN IN THE BARNÓWKO-LUBISZYN REGION (WESTERN POLAND) AS EVIDENCED BY THE COMPOSITION OF LIQUID HYDROCARBONS IN THE ZECHSTEIN MAIN DOLOMITE
Summary
Petroleum geochemical investigations were applied to continuity characterization of the Barnówko-Lubiszyn oil and gas deposit as well as satellite oil and gas traps Cychry, Namyślin, Zielin and Różańsko in western Poland - (Fig. 1). The whole oils and extracts of source rocks from the Zechstein Main Dolomite were analyzed with the use of high resolution gas chromatography and gas chromatography - mass spectrometry (GC-MS). The chromatographic fingerprints of the oils, as well as of the extracts from the Barnówko-Lubiszyn region are virtually identical (except of the Mostno-2 borehole), respectively. As is iIIustrated on star diagrams of several minor components peak ratios (Figs 2 and 3), these fingerprints of oils and core extracts deriving from boreholes of satellite traps are different, due to lack of communication with each other. GC-MS was used to evaluate the trace amounts of biomarkers present in oils and core extracts for providing valuable information on oil-oil and oil-source rock correlations. Constitution of polyalkylbenzenes, sesquiterpanes, n-alkylbenzenes and methylphenanthrenes (Figs 4-8) indicates that the hydrocarbons accumulated in the Barnówko-Lubiszyn basin derive from different source material than hydrocarbons found in the other traps. The usefulness of geochemical approach as an aid to solving basin evaluation problems (determination of sedimentary environment, kerogen maturity assessment, direction of hydrocarbons migration) is discussed. Presented data, when combined with geological and geophysical information, give a comprehensive picture of the basin being evaluated.
Summary
Petroleum geochemical investigations were applied to continuity characterization of the Barnówko-Lubiszyn oil and gas deposit as well as satellite oil and gas traps Cychry, Namyślin, Zielin and Różańsko in western Poland - (Fig. 1). The whole oils and extracts of source rocks from the Zechstein Main Dolomite were analyzed with the use of high resolution gas chromatography and gas chromatography - mass spectrometry (GC-MS). The chromatographic fingerprints of the oils, as well as of the extracts from the Barnówko-Lubiszyn region are virtually identical (except of the Mostno-2 borehole), respectively. As is iIIustrated on star diagrams of several minor components peak ratios (Figs 2 and 3), these fingerprints of oils and core extracts deriving from boreholes of satellite traps are different, due to lack of communication with each other. GC-MS was used to evaluate the trace amounts of biomarkers present in oils and core extracts for providing valuable information on oil-oil and oil-source rock correlations. Constitution of polyalkylbenzenes, sesquiterpanes, n-alkylbenzenes and methylphenanthrenes (Figs 4-8) indicates that the hydrocarbons accumulated in the Barnówko-Lubiszyn basin derive from different source material than hydrocarbons found in the other traps. The usefulness of geochemical approach as an aid to solving basin evaluation problems (determination of sedimentary environment, kerogen maturity assessment, direction of hydrocarbons migration) is discussed. Presented data, when combined with geological and geophysical information, give a comprehensive picture of the basin being evaluated.