Permskie skały zbiornikowe jako składowa systemu naftowego w rejonie Nowego Tomyśla (Polska Zachodnia)

The Nowy Tomyśl region is located near the northern edge of the Fore-Sudetic Monocline. In relation to the post-Variscan structural plan, this region is located near the border between the northern part of the Wolsztyn Ridge and the Poznań Basin. This spe¬cific location contributed to the occurrence of diverse sedimentary conditions during the development of the Lower and Upper Permian formations (alluvial, fluvial, aeolian and shallow-marine conditions). The natural gas and oilfields discovered in this area confirm the existence of an "active” petroleum system. However, a detailed analysis of geological, geochemical and reservoir data has shown that there are at least two such systems here (older and younger). Hydrocarbons occur in reservoir rocks of different ages (Carboniferous, Lower Permian, Upper Permian) and lithologies (clastic rocks, carbonate rocks). One of the crucial features of the reservoir rocks in the context of exploration for conventional fields is the preservation of favourable petrophysical properties (porosity, perme¬ability), allowing for the migration of hydrocarbons and their accumulation in reservoir traps. In the Permian formations of the Nowy Tomyśl region, such features are characteristic for the following formations: the Upper Rotliegend (1), the Zechstein Limestone (2) and the Main Dolomite (3). The first one occurs in interbeddings of aeolian and fluvial sandstones, occurring within alluvial fans developed north of the edge of the Wolsztyn Ridge. The second one is associated with the so-called reeffacies of the Zechstein Limestone developed in the northern part of this elevation, while the last concerns the carbonate platform formations of the Main Dolomite. The analysis of the Permian reservoir rocks in terms of their primary development (lithological and facies) and of the influence of diagenetic changes is critical. The most important thing, however, is not only the evaluation of the reservoir rocks, but their assessment as part of the analysis of the entire petroleum system.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).