alpshop2022-44, updated on 30 Aug 2022
https://doi.org/10.5194/egusphere-alpshop2022-44
15th Emile Argand Conference on Alpine Geological Studies
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Upper Campanian volcanoclastics in the Scaglia-type limestones of the Adria continental margin

David Gerčar1, Nina Zupančič1,2, Anna Waśkowska3, Jernej Pavšič1, and Boštjan Rožič1
David Gerčar et al.
  • 1Department of Geology, Faculty of Natural Sciences and Engineering, University of Ljubljana, Aškerčeva 12, Ljubljana, SI-1000, Slovenia
  • 2Ivan Rakovec Institute of Paleontology, ZRC SAZU, Novi trg 2, Ljubljana, SI-1000, Slovenia
  • 3Faculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, Mickiewicza 30, Kraków, 30-059, Poland

Upper Campanian Scaglia-type limestones in the transition zone between the Internal and External Dinarides (Placer 2008) contain two layers of bentonitic clays. The first 110 cm thick, and the second 10 cm thick. The geochemical composition of the bentonites indicates a rhyolitic volcanic source within an active continental margin. According to the mineralogy of the clay, the layers can be interpreted as deposition of volcanic-ash in a marine sedimentary environment with admixture of carbonates. The encompassing carbonate succession was deposited in a deeper marine environment of the Slovenian Basin. The limestones are composed of (hemi)pelagic mudstones to wackestones and thin- to medium-grained calcarenites, originating from the adjacent Adriatic Carbonate Platform. Similar Upper Cretaceous successions containing Campanian bentonitic clay horizons have been described in the Central Apennines (Graziano and Adabbo 1996; Bernoulli et al. 2004). The most likely source of these volcanoclastics is the bimodal rhyolitic/basaltic magmatic activity within the Sava suture zone, located in the present day Dinarides (Ustaszewski et al. 2009; Cvetković et al. 2014; Prelević et al. 2017; Schmid et al. 2020).

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How to cite: Gerčar, D., Zupančič, N., Waśkowska, A., Pavšič, J., and Rožič, B.: Upper Campanian volcanoclastics in the Scaglia-type limestones of the Adria continental margin, 15th Emile Argand Conference on Alpine Geological Studies, Ljubljana, Slovenia, 12–14 Sep 2022, alpshop2022-44, https://doi.org/10.5194/egusphere-alpshop2022-44, 2022.