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)
UNKP-17-2(Új Nemzeti Kiválósági Program) Támogató: Emberi Erőforrások Minisztériuma
Új Nemzeti Kiválóság Program, Felsőoktatási Doktori Hallgatói Kutatói Ösztöndíj(ÚNKP-20-3)
Támogató: Innovációs és Technológiai Minisztérium
Szakterületek:
Föld- és kapcsolódó környezettudományok
Természettudományok
Unraveling the age and kinematics of low temperature deformation events is crucial
in understanding the late‐stage evolution of orogens. However, accurate age constraints
can often be challenging to obtain due to unideal outcrop conditions, large sedimentary
hiatuses or the lack of well‐defined thermal events. In this study, we show on the
example of the Nekézseny Thrust, a poorly exposed late orogenic thrust in the southern
Western Carpathians, that a combined approach of structural analysis and multi‐method
thermochronology can provide the necessary temporal, kinematic and thermal constraints
for a detailed reconstruction of the deformation history. While structural mapping
revealed that the Late Cretaceous Uppony Gosau Basin in the footwall of the Nekézseny
Thrust underwent a significant post‐Campanian and pre‐Miocene shortening, K/Ar dating
of fault gouge samples from the main fault zone constrained the primary thrusting
event to the Maastrichtian. Based on the acquired apatite fission‐track and (U‐Th)/He
ages, subsequent heating of the Upper Cretaceous sediments due to tectonic burial
was limited to 75–100°C, followed by deformation‐related and gradual cooling between
the Eocene and Early Miocene. Considering the reconstructed deformation history, as
well as the large‐scale tectonic affinity of the displaced units in its footwall and
hanging wall, the Nekézseny Thrust is a far‐traveled (ca. 600 km) segment of the Late
Cretaceous Alps‐Dinarides contact zone, whose development was linked to the switch
from lower plate to upper plate position with respect to the Sava Zone and Alpine
Tethys sutures, respectively.