Austrian versus Hungarian bauxites in an Alpine tectonic context: a tribute to Prof. Andrea Mindszenty

Abstract

The correlation between the Cretaceous bauxites of Austria and Hungary was first highlighted by the pioneering work of Andrea Mindszenty in the 1980s. The physical distance today between these bauxite occurrences, located in the Northern Calcareous Alps and the Transdanubian Central Range, is on the order of hundred of kilometers. However, a semi-quantitative palinspastic reconstruction of their relative positions at the time of bauxite deposition during the Late Cretaceous (Turonian to early Santonian) shows their much closer proximity. Still, the important differences between these Upper Cretaceous bauxites are due to their different paleogeographic settings during their deposition on a subaerially exposed Eo-Alpine nappe substratum. Some other differences, such as porosity, are attributed to the subsequent tectonic overprint in the Alpine edifice. The Austrian and Hungarian bauxites not only record important information about of the syn-depositional geologic landscape but also provide clues about the pre- and post-depositional regional tectonic context of the areas where they developed. The typical setting for many of the Cretaceous bauxites in the broader Alpine region was uplift and karstification associated with the formation of various flexural basin systems. Therefore bauxites, in general, may contain important geologic information about the regional geodynamic processes, as it was pointed by Andrea Mindszenty, in a pioneering manner, already in the early 1990s.

Age, Kinematic and Thermal Constraints of Syn‐Orogenic Low‐Temperature Deformation Events: Insights From Thermochronology and Structural Data of the Nekézseny Thrust (Alpine‐Carpathian‐Dinaric Area)

“…At the same time, as the contractional deformation gradually migrated toward the northern foreland, subduction initiation occurred in the Alpine Tethys realm in the Late Cretaceous (South Penninic Ocean, Froitzheim et al., 2008; Schmid et al., 2008; Schuster et al., 2013; Plašienka, 2018). Part of the Late Cretaceous basins could be connected to this deformation, mainly in the Northern Calcareous Alps (Ortner, 2001; Plašienka & Soták, 2015; Wagreich, 1995), but also in the Transdanubian Range (Tari, 1994; Tari & Linzer, 2018). As a result, the main location of the north to northeast vergent nappe accretion was transferred from the Austroalpine basement nappes to the Pieniny Klippen Belt in the Western Carpathians (Figure 12a; Plašienka & Mikuš, 2010; Plašienka & Soták, 2015) and to the external front of the Lower Austroalpine domain in the Alps (Froiztheim et al., 2008).…”

“…In this study, we investigate the deformation history of the Nekézseny Thrust, a poorly exposed low-angle fault in the southernmost part of the Western Carpathians that bounds the Upper Cretaceous syn-orogenic sediments of the so-called Uppony Gosau Basin (Pelikán et al, 2005;Schréter, 1953). Similar deformed, dominantly siliciclastic successions, commonly referred to Gosau-type sediments (Hók et al, 2022;Kázmér et al, 2003;Ortner, 2001;Tari & Linzer, 2018;Wagreich, 1995;Wagreich & Faupl, 1994;Willingshofer et al, 1999), are known throughout the Alpine-Carpathian-Dinaric orogenic belt, and they may record both syn-orogenic flexural subsidence in front of emerging thrust sheets (Lužar-Oberiter et al, 2012;Matenco & Radivojević, 2012;Tari, 1995;Tari & Linzer, 2018) and/or orogen-parallel extension during the Late Cretaceous to Paleogene (Fügenschuh et al, 2000;Krohe, 1987;Madarás et al, 1996;Neubauer et al, 1995;Plašienka & Soták, 2015;Ratschbacher et al, 1989;Wagreich & Decker, 2001). Here, we combine detailed structural analysis with multi-method thermochronology to overcome the challenges resulting from the poor outcrop conditions and large sedimentary hiatuses.…”