Origin of Carpathian ozokerite deposits: determined from biomarkers and aromatic hydrocarbons distributions

Ozokerite deposits are rare, but their occurrences and origins can significantly contribute to studies of petroleum systems. Due to the excellent thermal and electrical insulation properties, ozokerite could be used in the energy sector, e.g., in the construction of heat storage tanks or in medicine to treat various ailments. In this study, the origin and process of ozokerite deposits formation are explained based on gas chromatography coupled with mass spectrometry (GC-MS) of oils, rock extracts, and ozokerite samples. The analyzed samples represent the most famous European ozokerite deposits, which are located in the Ukrainian Outer Carpathians, at Starunia and Boryslav. The results indicate that these ozokerites were generated from the source rocks that hosted mainly type II or II/III kerogen. These types of kerogen occur in the Oligocene-age Menilite Beds in Boryslav-Pokuttya and Skyba tectonic units of the Outer Carpathians. Our study demonstrates that, the ozokerite deposits are a product of geochromatographic effect - chromatography-like interaction between hot carrier gas (e.g., CO2), migrating oil and siliciclastic host rocks, which partially influence n-alkanes and linear-isoprenoid distribution but leave steranes and terpanes changed the least or unchanged.

Automated summary

This study explains the origin and formation process of ozokerite deposits based on gas chromatography-mass spectrometry analysis of samples. The results show that the ozokerite deposits in Ukraine are mainly derived from kerogen in the host rocks and the formation of ozokerite is influenced by a geochromatographic effect.