The collision between the Eurasian and Arabian plates along the 2400-km-long Bitlis-Zagros thrust zone isolated the Mediterranean from the Indian Ocean and has been linked to extension of the Aegean, rifting of the Red Sea, and the formation of the North and East Anatolian fault systems. However, the timing of the collision is poorly constrained, and estimates range from Late Cretaceous to late Miocene. Here, we report the fi rst apatite fissiontrack\ud
(AFT) ages from the Bitlis-Zagros thrust zone. The AFT samples are distributed over the 450 km length of the Bitlis thrust zone in southeast Turkey and include metamorphic\ud
rocks and Eocene sandstones. Despite the disparate lithology and large distance, the AFT ages point consistently to exhumation between 18 and 13 Ma. The AFT ages, along with a critical appraisal of regional stratigraphy, indicate that the last oceanic lithosphere between the Arabian and Eurasian plates was consumed by the early Miocene (ca. 20 Ma). The results imply that Aegean extension predated the Arabia-Eurasia collision
Apatite fission-track (FT) analyses of sandstone samples collected across the trace of the Ganos segment of the North Anatolian Fault (NAF) in south-western Thrace (Turkey) indicate that a significant structural discontinuity was in existence at least by the latest Oligocene. Such discontinuity had a complex kinematic history, as exhumation south of it occurred during the latest Oligocene and north of it during the mid-Miocene. Our data imply that early Pliocene westward propagation of the NAF in the Marmara region followed a pre-existing structural discontinuity; such discontinuity could be related to the development of the Intra-Pontide Suture, marking the terminal closure of the Intra-Pontide Ocean during the Oligocene.
Apatite fission‐track analyses along a W–E‐orientated transect across northern Corsica indicate an important episode of crustal exhumation in late early Miocene time. Samples taken from the Alpine orogenic wedge, from the adjacent foreland basin and from the crystalline basement complex flooring the basin are completely reset. This implies that a ≥ 2.0–2.3‐km‐thick crustal section made of thrust sheets and/or autochthonous foreland deposits has been removed by erosion since early Miocene time. A geometric projection of this lost cover towards the west indicates that all of northern Corsica was covered either by Alpine nappes or middle Eocene foreland deposits. Fission‐track ages are the same across the main boundary fault system separating the Alpine orogenic wedge and the foreland, indicating the absence of significant differential vertical displacement between upper and lower plates during Neogene unroofing.
Apatite fission-track analyses indicate that the Kazdag Massif in northwestern Anatolia was exhumed above the apatite partial annealing zone between 20 and 10 Ma (i.e. early-middle Miocene), with a cluster of ages at 17-14 Ma. The structural analysis of low-angle shear zones, high-angle normal faults and strike-slip faults, as well as stratigraphic analysis of upper-plate sedimentary successions and previous radiometric ages, point to a twostage structural evolution of the massif. The first stageencompassing much of the rapid thermal evolution of the massif-comprised late Oligocene-early Miocene low-angle detachment faulting and the associated development of small supradetachment grabens filled with a mixture of epiclastic, volcaniclastic and volcanic rocks (Küçükkuyu Fm.). The second stage (Plio-Quaternary) has been dominated by (i) strike-slip faulting related to the westward propagation of the North Anatolian fault system and (ii) normal faulting associated with present-day extension. This later stage affected the distribution of fission-track ages but did not have a component of vertical (normal) movement large enough to exhume a new partial annealing zone. The thermochronological data presented here support the notion that Neogene extensional tectonism in the northern Aegean region has been episodic, with accelerated pulses in the early-middle Miocene and Plio-Quaternary.
In this paper, we merge more than 200 new apatite and zircon (U-Th)/He analyses and 21 apatite fi ssion-track analyses from 71 new samples with previous published thermochronologic data using the same systems to understand the growth and largescale kinematics of the central Andes between 21°S and 28°S. In general, minimum dates decrease and the total range of dates increases from west to east across the range. Large variations in thermochronometer dates on the east side refl ect high spatial gradients in depth of recent erosional exhumation. Almost nowhere in this part of the Andes has Cenozoic erosion exceeded ~6-8 km, and in many places in the eastern half of the range, erosion has not exceeded 2-3 km, despite these regions now being
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