The relationship between syn‐ to post‐collisional orogenic shortening and stresses transmitted from other neighboring plate boundaries is important for understanding the kinematics of mountain belts, ...but has received little attention so far. The Apuseni Mountains are an example of an orogen in the interference zone between two other subduction systems located in the external Carpathians and Dinarides. This interference is demonstrated by the results of a combined thermochronological and structural field study that quantifies the post‐collisional latest Cretaceous–Tertiary evolution. The exhumation history derived from apatite fission track and (U‐Th)/He thermochronology indicates that the present‐day topography of the Apuseni Mountains originates mainly from latest Cretaceous times, modified by two tectonic pulses during the Paleogene. The latter are suggested by cooling ages clustering around ∼45 Ma and ∼30 Ma and the associated shortening recorded along deep‐seated fault systems. Paleogene exhumation pulses are similar in magnitude (∼3.5 km) and are coeval with the final collisional phases recorded in the Dinarides and with part of the Carpathian rotation around the Moesian promontory. These newly quantified Paleogene exhumation and shortening pulses contradict the general view of tectonic quiescence, subsidence and overall sedimentation for this time interval. The Miocene collapse of the Pannonian Basin did not induce significant regional exhumation along the western Apuseni flank, nor did the subsequent Carpathian collision. This is surprising in the overall context of Pannonian Basin formation and its subsequent inversion, in which the Apuseni Mountains were previously interpreted as being significantly uplifted in both deformation stages.
Key Points
Postcollisional evolution of Apuseni Mts. affected by nearby plate margin activity
Current topography created in latest Cretaceous modified by Paleogene tectonics
No major exhumation during Miocene Pannonian collapse and Carpathian collision
To date, research on neotectonics and related continental topography development has mostly focused on active plate boundaries characterized by generally high deformation rates. The intraplate ...sedimentary basins and rifts of the Northern Alpine foreland are associated with a much higher level of neotectonic activity than hitherto assumed. Seismicity and stress indicator data, combined with geodetic and geomorphologic observations, demonstrate that Europe's intraplate lithosphere is being actively deformed. This has major implications for the assessment of its natural hazards and environmental degradation. The lithosphere of the Northern Alpine foreland has undergone a polyphase evolution with an intense interplay between upper mantle thermal perturbations and stress-induced intraplate deformation that points to the importance of lithospheric folding of the thermally weakened lithosphere. In this paper, we address relationships between deeper lithospheric processes, neotectonics and surface processes in the Northern Alpine foreland with special emphasis on tectonically induced topography. The objectives are to quantify the effects of ongoing Alpine collision and Atlantic ridge-push on the intraplate deformation in Europe and its impact on topography evolution and related natural hazards.
This paper reviews the four-dimensional topographic evolution of the European lithosphere through a multi-disciplinary approach linking geology, geophysics and geotechnology. Until now, research on neotectonics and related topography development of intraplate regions has received little attention. Our study examines a number of selected natural laboratories in continental Europe. From orogen through platform to continental margin, these natural laboratories include the Carpathians–Pannonian system, the Northwest European Platform, Iberia and the Atlantic continental margin.
We focus on lithosphere memory and neotectonics with special attention to the thermo-mechanical structure of the lithosphere, mechanisms of large-scale intraplate deformation, Late-Neogene anomalies in subsidence and uplift, and links with surface processes and topography evolution.
The lithosphere of the Northern Alpine foreland has undergone a polyphase evolution during which interacting stress-induced intraplate deformation and upper mantle thermal perturbations controlled ...folding of the thermally weakened lithosphere. In this paper we address relationships among deeper lithospheric processes, neotectonics and surface processes in the Northern Alpine foreland with special emphasis on tectonically induced topography. We focus on lithosphere memory and neotectonics, paying special attention to the thermo-mechanical structure of the Rhine Graben System and adjacent areas of the northern Alpine foreland lithosphere. We discuss implications for mechanisms of large-scale intraplate deformation and links with surface processes and topography evolution.PUBLICATION ABSTRACT
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