Comparative petrography and organic geochemistry of different types of organic matter occurring in the Outer Carpathians rocks

Abstract

The char ac ter iza tion of or ganic mat ter (OM) in sed i men tary rocks is im por tant in many types of bi o log i cal, geo log i cal and envi ron men tal re search. The in te grated use of mi cros copy and geo chem is try, as here, is par tic u larly use ful in any at tempt to de fine the or i gin and evo lu tion of OM in sed i men tary bas ins. The or ganic pe trog ra phy and geo chem is try dif fer ent types of allogenic and authigenic OM from the Pol ish Outer Carpathian (POC) rocks were stud ied in pres ent study to com pare their ge netic type, ther mal ma tu rity, depositional en vi ron ment and post-sed i men ta tion pro cesses. Spe cial at ten tion was paid to re de pos ited coal clasts oc cur rences. The used tech niques show dif fer ences in or ganic mat ter type orig i nat ing from var i ous sources. The or ganic pe trog ra phy anal y sis shows that re de pos ited coal clasts (CC) and terrigenous or ganic mat ter (TOM) are com posed pre dom i nantly of woody ma te rial (the gas-prone Type-III kerogen). Sim i lar re sults were ob tained dur ing the Rock-Eval py rol y sis. More over, the GC-MS anal y sis of ex tracts in di cated the ad di tional source of OM, namely plank tonic organic mat ter (POM) with oil-prone kerogen Type-I or II. This OM is in some cases high ther mally ma ture and could po ten tially has allochthonous or i gin. The n-alkane, sat u rated and ar o matic biomarker data re vealed de po si tion of this POM in anoxic deltaic or close-shore sed i men tary en vi ron ments whereas the re de pos ited coal clasts were prob a bly orig i nally de pos ited in coal swamps as were the Up per Silesian bi tu mi nous coals.

New Opportunities for Oil and Gas Exploration in Poland—A Review

“…In the petroleum system developed in the Silesian Unit of the Outer Carpathians flysch belt, the Istebna and Krosno sandstones are assumed to be the principal reservoir rocks, in which gas and oil are accumulated in structural traps-fault-related synclines and anticlines, sealed by intercalations of fine-grained sediments, e.g., [70][71][72][73]. Hydrocarbons were generated from Menilite, Cieszyn, Verovice, and Lgota Beds (Figure 7), with TOC = 0.69-12.2%, locally exceeding 20%, and HI = 49-713 mg HC/g TOC in the former unit [74][75][76][77][78][79][80][81][82][83][84]. The process of generation of hydrocarbons has been continuous from the middle Miocene until the present in deep synclines and duplex zones in the Silesian Unit, e.g., [74].…”

Burial and Thermal History Modeling of the Paleozoic–Mesozoic Basement in the Northern Margin of the Western Outer Carpathians (Case Study from Pilzno-40 Well, Southern Poland)

“…Vitrinite reflectance (VR) values of the flysch strata range significantly, indicating a wide spectrum of thermal maturity. Generally, VR values point to immature to mature stages (oil windows) and, locally, to gas windows in different units of the Outer Carpathians [26][27][28][29].…”

Origin, migration and secondary processes of oil and natural gas in the western part of the Polish Outer Carpathians: geochemical and geological approach

“…The Carpathian fine-grained rocks (especially Oligocene Menilite and Krosno beds) often contain allochthonous, reworked organic material (Zielińska 2017;Waliczek et al 2019) from eroded Pennsylvanian-age rocks. These particles' contribution to the organic matter mass is variable and decreases with total organic carbon content (Zielińska et al 2020). In all oils collected from Silesian and Magurs nappes, β-carotane was identified (Table 6).…”