scholarly journals Late Cretaceous – Early Palaeogene inversion-related tectonic structures at the NE margin of the Bohemian Massif (SW Poland and northern Czechia)

2021 ◽  
Author(s):  
Andrzej Głuszyński ◽  
Pawel Aleksandrowski
Keyword(s):  
Late Cretaceous ◽  
Bohemian Massif ◽  
Wide Spectrum ◽  
Regional Scale ◽  
Crystalline Basement ◽  
Underground Mines ◽  
Normal Faults ◽  
Tectonic Structures ◽  
The North ◽  
Sedimentary Fill

Abstract. A brief, regional-scale review of the Late Cretaceous – Early Palaeogene inversion-related tectonic structures affecting the Sudetes and their foreland at the NE margin of the Bohemian Massif is presented and complemented with results of new seismic studies. The Sudetes expose Variscan-deformed basement, partly overlain by post-orogenic Permo-Mesozoic cover, containing a wide spectrum of tectonic structures, both brittle and ductile, in the past in this area referred to as young Saxonian or Laramide. We have used newly reprocessed legacy seismics to study these structures at the two main post-Variscan structural units of the area, the North-Sudetic and Intra-Sudetic synclinoria, and discuss the results together with regionally-distributed examples coming from quarries and underground mines as well as those from the literature. The Late Cretaceous – Early Palaeogene tectonic structures in consecutively reviewed Sudetic tectonic units, from the north to south, typically include gentle to moderate buckle folds of detachment type or fault-related, high-angle reverse and normal faults, as well as low-angle thrusts – often rooted in the crystalline basement. The structures hitherto described as grabens, are frequently believed to be bounded by reverse faults (hence we use the term ‘reverse grabens’) and typically reveal strongly synclinal pattern of their sedimentary fill. The crystalline basement top, as imaged by seismic sections in the North Sudetic Synclinorium below the detachment-folded cover, is synformally down-warped with a wavelength of up to 30 km, whereas on the elevated areas, where the basement top is exposed at the surface, it is up-warped (i.e. tectonically buckled). The reviewed compressional structures typically show an orientation fitting the regionally-known Late Cretaceous – Early Palaeogene tectonic shortening direction of NE-SW to NNE-SSW The same applies to the regional joint pattern, typically comprising an orthogonal system of steep joints of c. NW-SE and NE-SW strikes. All the reviewed structures are considered as due to the Late Cretaceous – Early Palaeogene tectonic shortening episode, although some of the discussed faults with a strike-slip component of motion may have been modified, or even produced, by later, Late Cenozoic, tectonism.

scholarly journals Polyphase evolution of Pelagonia (northern Greece) revealed by geological and fission-track data

Solid Earth ◽  
2015 ◽  
Vol 6 (1) ◽  
pp. 285-302 ◽  
Author(s):  
F. L. Schenker ◽  
M. G. Fellin ◽  
J.-P. Burg
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
Fission Track ◽  
Regional Scale ◽  
Normal Faults ◽  
Recent Sediment ◽  
Northern Greece ◽  
Rapid Cooling ◽  
Fission Track Ages ◽  
Pelagonian Zone

Abstract. The Pelagonian zone, situated between the External Hellenides/Cyclades to the west and the Axios/Vardar/Almopias zone (AVAZ) and the Rhodope to the east, was involved in late Early Cretaceous and in Late Cretaceous–Eocene orogenic events whose duration and extent are still controversial. This paper constrains their late thermal imprints. New and previously published zircon (ZFT) and apatite (AFT) fission-track ages show cooling below 240 °C of the metamorphic western AVAZ imbricates between 102 and 93–90 Ma, of northern Pelagonia between 86 and 68 Ma, of the eastern AVAZ at 80 Ma and of the western Rhodope at 72 Ma. At the regional scale, this heterogeneous cooling is coeval with subsidence of Late Cretaceous marine basin(s) that unconformably covered the Early Cretaceous (130–110 Ma) thrust system from 100 Ma. Thrusting resumed at 70 Ma in the AVAZ and migrated across Pelagonia to reach the External Hellenides at 40–38 Ma. Renewed thrusting in Pelagonia is attested at 68 Ma by abrupt and rapid cooling below 240 °C and erosion of the gneissic rocks. ZFT and AFT in western and eastern Pelagonia, respectively, testify at ~40 Ma to the latest thermal imprint related to thrusting. Central-eastern Pelagonia cooled rapidly and uniformly from 240 to 80 °C between 24 and 16 Ma in the footwall of a major extensional fault. Extension started even earlier, at ~33 Ma in the western AVAZ. Post-7 Ma rapid cooling is inferred from inverse modeling of AFT lengths. It occurred while E–W normal faults were cutting Pliocene-to-recent sediment.

Cornwallis Fold Belt and the mechanism of basement uplift

1977 ◽  
Vol 14 (6) ◽  
pp. 1374-1401 ◽  
Author(s):  
J. Wm. Kerr
Keyword(s):  
Sedimentary Cover ◽  
Basic Structure ◽  
Vertical Displacement ◽  
Crystalline Basement ◽  
Normal Faults ◽  
Late Devonian ◽  
Fold Belt ◽  
Early Devonian ◽  
The North ◽  
Sverdrup Basin

Cornwallis Fold Belt is a north-trending anticlinorium more than 650 km (400 mi) long, that extends from the Precambrian Shield to the Sverdrup Basin. It is the folded and faulted sedimentary suprastructure that overlies Precambrian crystalline basement rocks of the Boothia Horst. The horst and fold belt represent lower and intermediate levels of the Boothia Uplift. Evolution of the Cornwallis Fold Belt includes two phases, formation and modification.Formation. The basic structure of the Cornwallis Belt, a relatively simple, steep-sided, north-plunging anticlinorium, was formed in the interval from Proterozoic to Late Devonian time during several discrete phases of deformation that involved a similar stress pattern. These phases can be attributed to pulses of differential vertical uplift of the underlying Boothia Horst. The earliest phases involved periods of gentle arching of the crystalline basement and sedimentary cover in late Proterozoic and early Paleozoic times. The fold belt was formed mainly by the Cornwallis Disturbance (new name) which involved further differential vertical uplift, and comprised several pulses: (1) Early Silurian, mild, affecting only part of the belt; (2) Early Devonian, very strong, affecting the entire belt; (3) late Early Devonian, moderately strong, affecting the entire belt; (4) Late Devonian, moderately strong, affecting the entire belt. Each pulse was a cycle that began with uplift and erosion of the fold belt and shedding of detritus into the adjacent basins, and was followed by broader regional subsidence and the resumption of deposition on the belt. Between pulses of uplift there was regional subsidence, during which the fold belt subsided less than the flanking basins and received less sediments.Differential vertical displacement originated in the crystalline basement, occurring along fault zones that define the Boothia Horst, and are parallel to and controlled by a steep to vertical north-trending foliation. Faults extend into the sedimentary suprastructure comprising the overlying Cornwallis Fold Belt, and change gradually upward from vertical faults to high-angle reverse faults, overturned anticlines, and finally to asymmetric anticlines. Because the fold belt plunges north, this gradational sequence occurs from south to north in the exposed part of the fold belt. Structures formed by early pulses were rejuvenated by later pulses with the same sense of movement.Modification. The basic structure of the Cornwallis Fold Belt was modified by other types of deformation during the interval from Late Devonian to the present. Many of the preexisting faults were reactivated, but with a different sense of movement. During the Late Devonian to Middle Pennsylvanian Ellesmerian Orogeny, southward overriding of upper levels of the sedimentary succession produced folds in the rocks east and west of the Cornwallis Fold Belt which had not been previously deformed and could easily be displaced southward on an underlying décollement surface. The north-trending Cornwallis Fold Belt, however, was an obstacle to southward overriding in which the effects of overriding were reduced. Zones of interference structures developed near the margins, guided by older basement-controlled structures. Left-lateral faults were developed on the western margin and right-lateral movement is probable on the eastern margin.The Cornwallis Fold Belt extends an unknown distance northward beneath the younger rocks of the Sverdrup Basin. These younger rocks were deposited during a long period of northward downwarping that began in mid-Mississippian time. This same downwarping caused an abrupt increase in the northward plunge of the fold belt.During the Cretaceous–Tertiary Eurekan Rifting Episode the Cornwallis Fold Belt was fragmented by block faulting. The horsts form islands, and the grabens form submarine channels, some of which contain thick sections of semiconsolidated Cretaceous–Tertiary sediments. Numerous other normal faults that occur within the fold belt probably formed at this time. Cretaceous–Tertiary faults within the Cornwallis Fold Belt have a rectilinear pattern that was inherited from preexisting structures.

Oceanic crust generation in an island arc tectonic setting, SE Anatolian orogenic belt (Turkey)

2004 ◽  
Vol 141 (5) ◽  
pp. 583-603 ◽  
Author(s):  
OSMAN PARLAK ◽  
VOLKER HÖCK ◽  
HÜSEYİN KOZLU ◽  
MICHEL DELALOYE
Keyword(s):  
Late Cretaceous ◽  
Subduction Zones ◽  
Wide Spectrum ◽  
Tectonic Setting ◽  
Volcanic Rocks ◽  
Orogenic Belt ◽  
Mature Stage ◽  
Magmatic Arc ◽  
The North ◽  
Suprasubduction Zone

A number of Late Cretaceous ophiolitic bodies are located between the metamorphic massifs of the southeast Anatolian orogenic system. One of them, the Göksun ophiolite (northern Kahramanmaraş), which crops out in a tectonic window bounded by the Malatya metamorphic units on both the north and south, is located in the EW-trending nappe zone of the southeast Anatolian orogenic belt between Göksun and Afşin (northern Kahramanmaraş). It consists of ultramafic–mafic cumulates, isotropic gabbro, a sheeted dyke complex, plagiogranite, volcanic rocks and associated volcanosedimentary units. The ophiolitic rocks and the tectonically overlying Malatya–Keban metamorphic units were intruded by syn-collisional granitoids (∼ 85 Ma). The volcanic units are characterized by a wide spectrum of rocks ranging in composition from basalt to rhyolite. The sheeted dykes consist of diabase and microdiorite, whereas the isotropic gabbros consist of gabbro, diorite and quartzdiorite. The magmatic rocks in the Göksun ophiolite are part of a co-magmatic differentiated series of subalkaline tholeiites. Selective enrichment of some LIL elements (Rb, Ba, K, Sr and Th) and depletion of the HFS elements (Nb, Ta, Ti, Zr) relative to N-MORB are the main features of the upper crustal rocks. The presence of negative anomalies for Ta, Nb, Ti, the ratios of selected trace elements (Nb/Th, Th/Yb, Ta/Yb) and normalized REE patterns all are indicative of a subduction-related environment. All the geochemical evidence both from the volcanic rocks and the deeper levels (sheeted dykes and isotropic gabbro) show that the Göksun ophiolite formed during the mature stage of a suprasubduction zone (SSZ) tectonic setting in the southern branch of the Neotethyan ocean between the Malatya–Keban platform to the north and the Arabian platform to the south during Late Cretaceous times. Geological, geochronological and petrological data on the Göksun ophiolite and the Baskil magmatic arc suggest that there were two subduction zones, the first one dipping beneath the Malatya–Keban platform, generating the Baskil magmatic arc and the second one further south within the ocean basin, generating the Göksun ophiolite in a suprasubduction zone environment.

scholarly journals Transversely isotropic lower crust of Variscan central Europe imaged by ambient noise tomography of the Bohemian Massif

Solid Earth ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 1051-1074
Author(s):  
Jiří Kvapil ◽  
Jaroslava Plomerová ◽  
Hana Kampfová Exnerová ◽  
Vladislav Babuška ◽  
György Hetényi ◽  
...  
Keyword(s):  
Bohemian Massif ◽  
Lower Crust ◽  
Ambient Noise ◽  
Regional Scale ◽  
Crustal Thickening ◽  
Scale Model ◽  
Significant Feature ◽  
Ambient Noise Tomography ◽  
North East ◽  
The North

Abstract. The recent development of ambient noise tomography, in combination with the increasing number of permanent seismic stations and dense networks of temporary stations operated during passive seismic experiments, provides a unique opportunity to build the first high-resolution 3-D shear wave velocity (vS) model of the entire crust of the Bohemian Massif (BM). This paper provides a regional-scale model of velocity distribution in the BM crust. The velocity model with a cell size of 22 km is built using a conventional two-step inversion approach from Rayleigh wave group velocity dispersion curves measured at more than 400 stations. The shear velocities within the upper crust of the BM are ∼0.2 km s−1 higher than those in its surroundings. The highest crustal velocities appear in its southern part, the Moldanubian unit. The Cadomian part of the region has a thinner crust, whereas the crust assembled, or tectonically transformed in the Variscan period, is thicker. The sharp Moho discontinuity preserves traces of its dynamic development expressed in remnants of Variscan subductions imprinted in bands of crustal thickening. A significant feature of the presented model is the velocity-drop interface (VDI) modelled in the lower part of the crust. We explain this feature by the anisotropic fabric of the lower crust, which is characterised as vertical transverse isotropy with the low velocity being the symmetry axis. The VDI is often interrupted around the boundaries of the crustal units, usually above locally increased velocities in the lowermost crust. Due to the north-west–south-east shortening of the crust and the late-Variscan strike-slip movements along the north-east–south-west oriented sutures preserved in the BM lithosphere, the anisotropic fabric of the lower crust was partly or fully erased along the boundaries of original microplates. These weakened zones accompanied by a velocity increase above the Moho (which indicate an emplacement of mantle rocks into the lower crust) can represent channels through which portions of subducted and later molten rocks have percolated upwards providing magma to subsequently form granitoid plutons.

Upper plate deformation during blueschist exhumation, ancestral western California forearc basin, from stratigraphic and structural relationships at Mount Diablo and in the Rio Vista Basin

2021 ◽  
Author(s):  
Jeffrey Unruh
Keyword(s):  
San Francisco ◽  
Late Cretaceous ◽  
Normal Faults ◽  
Coast Range ◽  
Forearc Basin ◽  
Bay Area ◽  
The North ◽  
Early Tertiary ◽  
Local Equivalent ◽  
Structural Relief

ABSTRACT Late Cenozoic growth of the Mount Diablo anticline in the eastern San Francisco Bay area, California, USA, has produced unique 3D exposures of stratigraphic relationships and normal faults that record Late Cretaceous uplift and early Tertiary extension in the ancestral California forearc basin. Several early Tertiary normal faults on the northeast flank of Mount Diablo have been correlated with structures that accommodated Paleogene subsidence of the now-buried Rio Vista basin north of Mount Diablo. Stepwise restoration of deformation at Mount Diablo reveals that the normal faults probably root into the “Mount Diablo fault,” a structure that juxtaposes blueschist-facies rocks of the Franciscan accretionary complex with attenuated remnants of the ophiolitic forearc basement and relatively unmetamorphosed marine forearc sediments. This structure is the local equivalent of the Coast Range fault, which is the regional contact between high-pressure Franciscan rocks and structurally overlying forearc basement in the northern Coast Ranges and Diablo Range, and it is folded about the axis of the Mount Diablo anticline. Apatite fission-track analyses indicate that the Franciscan rocks at Mount Diablo were exhumed and cooled from depths of 20+ km in the subduction zone between ca. 70−50 Ma. Angular unconformities and growth relations in the Cretaceous and Paleogene stratigraphic sections on the northeast side of Mount Diablo, and in the Rio Vista basin to the north, indicate that wholesale uplift, eastward tilting, and extension of the western forearc basin were coeval with blueschist exhumation. Previous workers have interpreted the structural relief associated with this uplift and tilting, as well as the appearance of Franciscan blueschist detritus in Late Cretaceous and early Tertiary forearc strata, as evidence for an “ancestral Mount Diablo high,” an emergent Franciscan highland bordering the forearc basin to the west. This outer-arc high is here interpreted to be the uplifted footwall of Coast Range fault. The stratigraphic and structural relations exposed at Mount Diablo support models for exposure of Franciscan blueschists primarily through syn-subduction extension and attenuation of the overlying forearc crust in the hanging wall of the Coast Range fault, accompanied by (local?) uplift and erosion of the exhumed accretionary prism in the footwall.

Alpine tectonic evolution of the Northern Serbo-Macedonian sub-unit: inferences from kinematic and petrological investigations

2021 ◽  
Author(s):  
Bojan Kostić ◽  
Uroš Stojadinović ◽  
Nemanja Krstekanić ◽  
Marija Ružić ◽  
Aleksa Luković
Keyword(s):  
Continental Margin ◽  
Late Cretaceous ◽  
Pannonian Basin ◽  
Oceanic Lithosphere ◽  
Normal Faults ◽  
Low Grade ◽  
The South ◽  
The North ◽  
Neogene Sediments ◽  
Subduction System

<p>The Serbo-Macedonian Massif represents a belt of medium to lower amphibolite facies metamorphics situated along the European continental margin between the Pannonian Basin in the north and the Aegean Sea in the south. Structurally, it comprises the innermost segments of the Dacia mega-unit of the European affinity and is juxtaposed against the Adria-derived units of the Dinarides across the Adria-Europe zone of collision. The peak metamorphic event in the Serbo-Macedonian Massif is Variscan in age, while its magmatism had a complex pre-Alpine evolution, with the youngest stage being related to the crustal extension during the Triassic opening of the northern branch of Neotethys Ocean (or the Vardar Ocean). The subsequent Late Jurassic–Paleogene closure of the Vardar Ocean led to the E-ward subduction of the Neotethys oceanic lithosphere beneath the upper European plate (i.e., the Sava subduction system). The retreating and steepening of subducting lithosphere during the Late Cretaceous triggered syn-subductional extension in the upper plate of the Sava subduction system. The Late Cretaceous extension exhumed and structurally juxtaposed<strong> </strong>the high-grade Serbo-Macedonian metamorphics against the low-grade metamorphics of the Carpathians Supragetic Unit. The contact is marked by the E-dipping shear zone that can be traced along the eastern margin of Serbo-Macedonian Massif, from the Vršac Mts in the north, across the Jastrebac Mts and further towards the south in the Central Serbo-Macedonian sub-unit of south-eastern Serbia. The Late Cretaceous extension exhumed the Serbo-Macedonian metamorphic core, concurrently creating subsidence in a forearc basin along the frontal part of the European continental margin.</p><p>Due to its unique position in the interference zone of the two retreating Carpathian and Dinaridic slabs, the Northern Serbo-Macedonian sub-unit between the Vršac Mts in the north and the Jastrebac Mts in the south was strongly influenced by processes associated with the Oligocene–Miocene Pannonian extension. Hence, large segments of the Northern Serbo-Macedonian sub-unit including its contact with the Supragetic Unit were buried beneath the Neogene sediments of the Morava Valley Corridor, as the southern prolongation of the Pannonian Basin. In order to segregate and quantify the effects of the Oligocene–Miocene extension we have conducted a coupled kinematic, petrological and thermochronological study in the segments of Northern Serbo-Macedonian sub-unit adjacent to the Dinarides and Carpathians. The recent tectonic uplift of the Vršac Mts occurred in the Middle to Late Miocene along the WSW-dipping normal faults that control deposition in the adjacent Zagajica depression. The ENE-WSW oriented extension, which was triggered by the retreat of Carpathian slab, exhumed the core of the mountains and exposed the Late Cretaceous Serbo-Macedonian\Supragetic extensional contact. South from the Vršac Mts such exhumation was hampered by the presence of rigid Moesian indenter. Tectonic exhumation of the Jastrebac Mts, together with a cluster of Serbo-Macedonian gneiss domes that emerge from the surrounding Neogene sediments in the western-central part of the Morava Valley Corridor, was induced by corrugated detachment faults during the Oligocene–Miocene E-W oriented Dinaridic extension.</p>

scholarly journals Tectonic domains and exhumation history of the Omineca Belt in southeastern British Columbia from 40Ar/39Ar thermochronology

2020 ◽  
Vol 57 (8) ◽  
pp. 918-946
Author(s):  
Ewan R. Webster ◽  
Douglas A. Archibald ◽  
David R.M. Pattison ◽  
Jessica A. Pickett ◽  
Joel C. Jansen
Keyword(s):  
British Columbia ◽  
Late Cretaceous ◽  
Regional Scale ◽  
Metamorphic Rocks ◽  
Normal Faults ◽  
Canadian Cordillera ◽  
Data Set ◽  
Rapid Cooling ◽  
Central Domain ◽  
Eastern Domain

A large geochronological data set comprising 40Ar/39Ar and K–Ar (hornblende, muscovite, biotite, and K-feldspar), Rb–Sr (muscovite), fission track (zircon and apatite) and U–Pb (zircon and monazite) dates has been compiled for the southern Kootenay Arc and western Purcell anticlinorium in the Omineca Belt of the Canadian Cordillera in southeastern British Columbia. New 40Ar/39Ar data for hornblende, muscovite, biotite, and alkali feldspar are presented and combined with data from other studies. We integrate these data with recent advances in the geology of the region to define three partially fault-bounded domains with differing geological and exhumation histories, here termed the western, central, and eastern domains. The western domain is characterized by (1) late synkinematic Jurassic plutons with hornblende, muscovite, and biotite 40Ar/39Ar plateau dates between 170 and 165 Ma, some of which are within error of the U–Pb zircon dates for these plutons, and (2) late Early Cretaceous (118–102 Ma) plutons commonly with concordant mica 40Ar/39Ar plateau dates of a similar age range, indicating rapid cooling following emplacement of both suites. The central domain is bounded by regional-scale normal faults (Gallagher and Midge Creek faults, Blazed Creek/Next Creek faults, and Purcell Trench fault) and contains superposed Early and Late Cretaceous zones of Barrovian metamorphic rocks and several mid- to Late Cretaceous, post-kinematic plutons. The transition from the western domain into the central domain is characterized by 40Ar/39Ar mica age spectra showing a progression of increasing thermal overprinting. Along the north–south length of the central domain, biotite and muscovite yield Paleocene to Eocene K–Ar and 40Ar/39Ar plateau dates between 66 and 40 Ma. The eastern domain consists of (1) a southern portion that occurs in the hanging wall of the Purcell Trench fault, comprising mid-Cretaceous intrusions of the Bayonne magmatic suite emplaced into biotite zone metasedimentary rocks of the Mesoproterozoic Belt-Purcell Supergroup in the western Purcell anticlinorium, and (2) a northern portion that shows a continuous transition with the northern part of the central domain north of the terminus of the Purcell Trench fault. Cretaceous igneous rocks in the southern portion of the eastern and western domains have 40Ar/39Ar mica plateau dates that are <9 Myr younger than U–Pb zircon dates, indicating rapid cooling shortly after emplacement. 40Ar/39Ar step-heating reveals that there was a mid- to Late Cretaceous thermal disturbance in the eastern domain, possibly related to emplacement of younger plutons at deeper crustal levels and the Late Cretaceous Barrovian metamorphic event recorded in rocks of the central domain, such that biotite with dates <ca. 73 Ma yield plateau age spectra but those with older dates are disturbed. The new geochronology, combined with recent mapping and metamorphic studies, leads to the conclusion that the exhumation of the Barrovian metamorphic rocks of the central domain was a multi-stage process. The central domain experienced rapid tectonic decompression and minor pluton emplacement in the Late Cretaceous to early Paleocene (76–61 Ma) when the Cordilleran orogen was under regional contraction during which most of the exhumation occurred. Final exhumation in the footwall of Eocene normal faults was less significant and occurred between 53 and ca. 46 Ma when the Cordilleran orogen had transitioned to regional extension, by which time the three domains had attained a similar crustal level. These episodes of exhumation are similar to those found in other core complexes in the southern Canadian Cordillera and contiguous northern Idaho and Washington. The earlier episode is coincident with regional-scale, Late Cretaceous thrust faulting in the Foreland Belt of the Rocky Mountains. Eocene normal faulting and final exhumation of core complexes in the Omineca Belt mark the end of contraction in the Foreland Belt.

scholarly journals Polyphase evolution of Pelagonia (northern Greece) revealed by geological and fission-track data

2014 ◽  
Vol 6 (2) ◽  
pp. 3075-3109 ◽  
Author(s):  
F. L. Schenker ◽  
M. G. Fellin ◽  
J.-P. Burg
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
Fission Track ◽  
Regional Scale ◽  
Normal Faults ◽  
Recent Sediment ◽  
Northern Greece ◽  
Rapid Cooling ◽  
Basement Rocks ◽  
Fission Track Ages

Abstract. The Pelagonian zone, between the External Hellenides/Cyclades to the west and the Axios/Vardar/Almopia zone (AVAZ) and Rhodope to the east, was involved in late Early Cretaceous and in Late Cretaceous-Eocene orogenic events whose duration are still controversial. This work constrains their late thermal imprints. New and previously published zircon (ZFT) and apatite (AFT) fission-track ages show cooling below 240°C of the metamorphic western AVAZ imbricates between 102 and 93–90 Ma, of northern Pelagonia between 86 and 68 Ma, of the eastern AVAZ at 80 Ma and of western Rhodope at 72 Ma. At the regional scale, this heterogeneous cooling is coeval with subsidence of Late Cretaceous marine basin(s) that unconformably covered since 100 Ma the Early Cretaceous (130–110 Ma) thrust system. Thrusting restarted at 70 Ma in the AVAZ and migrated across Pelagonia to reach the External Hellenides at 40–38 Ma. Renewed thrusting in Pelagonia is attested at 68 Ma by abrupt and rapid cooling below 240°C and erosion of the basement rocks. ZFT and AFT in western and eastern Pelagonia, respectively, set at 40 Ma the latest thermal imprint related to thrusting. Central-eastern Pelagonia cooled rapidly and uniformly from 240 to 80°C between 24 and 16 Ma in the footwall of a major extensional fault. Extension started even earlier, at 33 Ma in the western AVAZ. Post-7 Ma rapid cooling is inferred from inverse modeling of AFT lengths. It occurred while E–W normal faults were cutting Pliocene-to-recent sediment.

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