Building and exhumation of the Western Carpathians: New constraints from sequentially restored, balanced cross sections integrated with low-temperature thermochronometry

Western Carpathian orogeny has been the subject of intense scientific debate due to the occurrence of enigmatic features, leading several authors to provide contrasting geological models. In this paper, a new interpretation for the tectonic evolution of the Western Carpathians is provided based on the following: (i) an analysis of the stratigraphy of the Mesozoic-Tertiary successions across the thrust belt domains, (ii) a reappraisal of the stratigraphy and sedimentology of the “tectonic mélange” (i.e., the so-called Pieniny Klippen Belt) marking the suture between the Inner and Outer Carpathians, and (iii) the construction of a series of balanced and restored cross sections, validated by 2-D forward modeling. Our analysis provides a robust correlation of the stratigraphy from the Outer to the Inner Carpathians, independently of the occurrence of oceanic lithosphere in the area, and allows for the reinterpretation of the tectonic relationships among the Inner Carpathians, the Outer Carpathians, and the Pieniny Klippen Belt and the exhumation mechanisms affecting this orogenic belt. In order to constrain the evolution during the last 20 Ma, our model also integrates previously published and new apatite fission track and apatite (U-Th-Sm)/He data. These latter indicate a middle-late Miocene exhumation of the Pieniny Klippen Belt. In this study, the recent regional uplift of the Pieniny Klippen Belt is described for the first time using a 2-D kinematic model for the tectonic evolution of the Western Carpathians