Master of Science Julian Janocha will Tuesday May 26th, 2026, at 12:15 hold his Thesis Defense for the PhD degree in Science. The title of the thesis is:
« Tectonosedimentary evolution of upper Palaeozoic rift basins on Svalbard: Sediment provenance, rift dynamics, and implications for petroleum potential on the Barents Shelf »
This PhD thesis investigates the post-Caledonian pre- and syn-rift sedimentary succession of the upper Palaeozoic, with a focus on the southernmost exposures on Svalbard, specifically Bjørnøya and Hornsund. The primary objective was to unravel the tectonostratigraphic evolution of these successions, with an emphasis on sediment provenance, source rock potential, and petroleum exploration potential on the Barents Shelf.
The pre-rift Billefjorden Group represents the oldest sedimentary succession unaffected by the Caledonian orogeny, deposited in warm, humid terrestrial wetlands. In contrast, the syn-rift Gipsdalen Group developed in arid half-grabens across Svalbard and the Barents Shelf. This thesis is composed of three research papers that collectively address key aspects of the upper Palaeozoic succession.
The first paper evaluates the source rock potential and depositional environment of the upper Palaeozoic succession on Bjørnøya. Results indicate that the Billefjorden Group exhibits the greatest source rock potential, with organic matter-rich intervals deposited in fluvial floodplain settings. However, deep burial and high thermal maturity of the samples limit petroleum generation potential in the Carboniferous and Permian successions. The thin and laterally complex organic-rich intervals of the Billefjorden Group pose challenges in assessing the volume of expelled hydrocarbons.
The second paper focuses on the detrital zircon composition of the Billefjorden Group on Bjørnøya to identify sediment source areas and potential changes in catchment dynamics. Sedimentological analysis reveals north-westward-flowing axial meandering streams and north-eastward-flowing transverse braided streams. Despite these competing drainage directions, the detrital zircon spectrum remains highly polymodal, suggesting a dominant sediment source in northeast Greenland with no significant changes in provenance throughout the deposition of the Billefjorden Group.
The third paper extends the detrital zircon dataset to include the Billefjorden and Gipsdalen groups across Svalbard. The findings reveal that the Billefjorden Group was sourced from different catchments at various locations on Svalbard, challenging the traditional view of a large, connected sag basin. Instead, the data suggest deposition in a sag basin intersected by local highs, with northeast Greenland as the primary sediment source. For the Gipsdalen Group, deposited in narrow rift basins, no significant shift in sediment provenance was observed for the westernmost upper Palaeozoic basins. However, in the Billefjorden Trough, increased dominance of a single sediment source indicates greater basin isolation during continued subsidence.
Overall, this thesis provides new insights into the tectonostratigraphic evolution, sediment provenance, and petroleum potential of the upper Palaeozoic successions on Svalbard, with implications for understanding the broader Barents Shelf region.
Supervisory Committee:
1st Opponent: Dr. Peter Klitzke, BGR - Federal Institute for Geosciences and Natural Resources, Germany
2nd Opponent: Professor Dr. Pieter Vermeesch, University College London, England, United Kingdom
Internal member and leader of the committee: Professor Dr. Andreia Plaza-Faverola, UiT