The VICCO talk is helt by: Geoffroy Mohn and Julie Tugend, CY Cergy Paris University, France.
Palaeobathymetry and magmatic evolution the Mid-Norwegian volcanic margin
Abstract:
The Mid-Norwegian and NE-Greenland conjugate volcanic rifted margins overlaps in time with the Paleocene Eocene Thermal Maximum (PETM), a rapid global warming episode likely triggered by thermogenic gas release through hydrothermal vents during the sill emplacement as shown by IODP Expedition 396. However, a comprehensive regional assessment of the water depth at which hydrothermal venting occurred remains necessary to validate the overall impact on paleoclimate. To do so, we apply 3D flexural-backstripping and decompaction to remove the loading effects of sedimentary sequences and determine the sediment-corrected bathymetry down to the top Palaeocene surface at which most of the vents are mapped.
We use local palaeobathymetric constraints from seismic observations and drilled biostratigraphic data, combined with our flexural backstripping and decompaction results to calibrate palaeobathymetric variations of the Paleocene venting surface at the time of the PETM.
Our results predict that hydrothermal venting occurred within a range of palaeo-water depths showing the complex palaeo-structure of the top Paleocene surface. Key post-Paleocene tectonic influences such as a well-documented Miocene doming episode influence the margin history, and hence, at this location, our palaeobathymetric results represent shallowest estimates and must be interpreted with caution. However, most of the vents (>80%) restore to bathymetries shallower than 500 meters, i.e., in sub-aerial to shallow marine conditions.
BIO:
Julie Tugend is junior professor at CY Cergy-Paris University (France) since 2024. She obtained her PhD from the University of Strasbourg in 2013. Her postdoctoral research at the Ecole Normale supérieure in Paris, between the Universities of Strasbourg and Liverpool (United Kingdom) and at Sorbonne Université (Paris), focused on the structural, magmatic and stratigraphic analysis of continental passive margins. Coupling seismic and field observations to geodynamic quantitative analyses, she investigates the spatial and temporal evolution of subsidence and palaeobathymetry during continental breakup and oceanic spreading.
Geoffroy Mohn is associate professor in Tectonics at CY Cergy-Paris University (France) since 2012. He obtained his PhD from the University of Strasbourg in 2010 followed by a postdoctoral scholarship between the University of Strasbourg (France), University of Lausanne (Switzerland) and EXXONMOBIL-Upstream Research Company-Houston. His research focuses on the mechanisms of continental lithospheric thinning and breakup and the associated magmatic and sedimentary record using offshore and onshore case studies. He also investigates the interaction between hyperextension and evaporite/salt deposition and the effect of mobile salt on the stratigraphic architecture of rift basins. Dr Geoffroy Mohn is involved in IODP, he participated and sailed on the IODP expeditions 368 and 396.
-------
About the VICCO+ seminar series
The seminars are open for everyone interested, and especially students are welcome. The talks in VICCO+ seminar series are offered by the The VICCO centre, Dept. of Geosciences, University of Oslo.
The VICCO+ talk seminar series are normally held in the Geology Building, at UiO's campus Blindern, see this map.
The Co-ordinator for the talks is
– Bjørgunn Heggem Dalslåen