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Whether Archean tectonics were horizontally or vertically dominated is controversially discussed because arguments bear on the kinematics and thermal state of the Archean mantle and constrain the mode of formation of the earliest continental crust. Highly deformed strata of Archean greenstone belts figure prominently in this debate because they record long periods of time and multiple deformation phases. Among the best‐preserved greenstone belts counts the Barberton Greenstone Belt (BGB) of southern Africa. Geological mapping of part of the southern BGB in Eswatini (Swaziland), combined with U‐Pb zircon dating, shows that the region preserves a tightly re‐folded imbricate thrust stack in which metavolcanic and ‐volcaniclastic strata of the Onverwacht Group, deposited at 3.34–3.29 Ga, have been thrust on top of ca. 3.22 Ga siliciclastic strata of the Moodies Group. The structurally highest element, the Malolotsha Syncline, forms a tectonic klippe of substantial size and is >1,450 m thick. Forward modeling of a balanced cross section indicates that this thrust stack was part of a northwestward‐verging orogen along the southern margin of the BGB and records a minimum horizontal displacement of 33 km perpendicular to its present‐day faulted, ductily strained and multiply metamorphosed margin. Because conglomerate clasts indicate a significantly higher degree of prolate strain which extends further into the BGB than at its northern margin, late‐stage tectonic architecture of the BGB may be highly asymmetrical. Our study documents that the BGB, and perhaps other Archean greenstone belts, preserves a complex array of both vertically‐ and horizontally‐dominated deformation styles that have interfered with each other at small regional and short temporal scales., Plain Language Summary: Worldwide, only a few regions exist where ancient rock strata document how earth cooled, surface strata deformed, and continents grew. It is debated whether vertical movements dominated (akin to a lava lamp) and when major horizontal motions (as they dominate Earth today) began; certainly, there was also overlap between these regimes. Radiometric age dating of zircons extracted from strata along the southern margin of one of the best‐preserved ancient regions in southern Africa, the Barberton Greenstone Belt in Eswatini, show that older strata were thrust there over younger strata for at least 33 km distance subhorizontally. Then they were shingled, and then folded. The results show that even at a time when Earth's oldest continents were just forming, significant horizontal displacements existed already., Key Points: U‐Pb zircon dating and geological mapping confirm a folded thrust‐stack along part of the southern margin of the Archean Barberton Greenstone Belt (BGB). Forward modeling of a balanced cross‐section indicates >33 km of horizontal shortening toward the northwest. Vertically‐ and horizontally‐dominated tectonics interfered with each other in the BGB and may have done so in other Archean greenstone belts as well., Friedrich‐Schiller‐University Jena, https://doi.org/10.5880/fidgeo.2022.037

The Dinarides fold and thrust belt resulted from the collision of the Adriatic Microplate with Eurasia and shows an overall SW-vergent and in-sequence structural architecture. In the Paleocene the ophiolite-bearing internal Dinarides were exclusively affected by crustal shortening. The outward SW propagation of the deformation front reached the eastern Adriatic passive continental margin mainly composed of Mesozoic carbonate platform rocks in Mid-Eocene times. This led to high crustal Mid Eocene to Oligocene shortening and the formation of the external Dinarides. Two balanced crosssections across the external Dinarides show an along-strike contrasting deformation style observed in two orogenic segments separated by the 250 km long dextrally transpressive Split-Karlovac Fault: the southern segment dominated by SW-vergent forethrusts, and the northern segment dominated by NE-vergent backthrusts, located to the SE and NW from the Split-Karlovac Fault, respectively. So far, it is not known why the regionally rather uniform Mesozoic Adriatic carbonate platform sequence had undergone such contrasting along-strike deformation. To improve the understanding of the initiation of the NE-vergent backthrusts and to assess the amount of crustal shortening in the NW segment, a 2D kinematic forward model across the central Velebit Mt. was set up. The Velebit Mt. extends for about 130 km along the eastern Adriatic coast and form a SW-dipping monocline with topographic elevations reaching close to 1800 m. This faultrelated monocline is formed in the hanging wall of a NE-vergent backthrust system. The 2D kinematic forward model approach applied to a pre-deformed lithostratigraphic template scaled to reported stratigraphic thicknesses enabled us to test various geometries and temporal successions of fault activity not only for the Mid Eocene – Oligocene contraction, but also for the Mesozoic passive margin extension. Through an iterative trial-and-error method, we were able to reproduce the present-day deformed reference section across the Velebit Mt. and the Lika Plateau in its northeastern hinterland. Our best-fit balanced kinematic model suggests that the reactivation of Middle Triassic and Upper Jurassic basement-rooted half grabens played a key role in the initiation of the backthrusts. These half grabens were mainly reactivated by hanging wall shortcuts. This inversion of normal faults led to predetermination of the thin-skinned NE-vergent back thrusts, forming the upper part of a complex 68 km wide triangle structure. The structurally lower part comprised of a SW-vergent antiformal stack involving Paleozoic basement. We assessed a crustal shortening for the triangle structure of 47 km and a shortening of 98 km for the entire cross-section. Our results show that the differences in both the lithostratigraphic and Mesozoic halfgrabens along the eastern Adriatic passive margin played a crucial role in the Mid Eocene – Oligocene deformation of the external part of the Dinarides fold and thrust belt, which led to the contrasting along strike deformation styles to the NW and SE of the Split-Karlovac Fault.

Extension across the southern Pannonian Basin and the internal Dinarides is characterized by Oligo���Miocene metamorphic core complexes (MCCs) exhumed along mylonitic low���angle extensional shear zones. Cer MCC at the transition between Dinarides and Pannonian Basin occupies a structural position within the distal���most Adriatic thrust sheet and originates from two different tectonic processes: Late Cretaceous���Paleogene nappe���stacking during a continent���continent collision with Adria in a lower plate position, and exhumation related to Miocene extension driven by the Carpathian slab���rollback. Structural data and a balanced cross section across the Cer massif show linking of the exhuming shear zone to a breakaway fault, which reactivated the early Late Cretaceous most internal nappe contact. Paleozoic greenschist���to amphibolite���grade lithologies surround a polyphase intrusion composed of I��� and S���type granites and were exhumed along a shear zone characterized by top���N transport. Thermobarometric analyses indicate an intrusion depth of 7���8 km of the Oligocene I���type granite; cooling below ���500��C occurred at 25.4 �� 0.6 Ma (1��) yielded by 40Ar/39Ar dating of hornblende. Biotite and white mica from this intrusion as well as from the mylonitic shear zone yield 40Ar/39Ar cooling ages of 17���18 Ma independent of the used techniques (in situ laser ablation, single���grain total fusion, single���grain step heating, and multi���grain step heating). White mica from the S���type granite yield an 40Ar/39Ar cooling age of 16.7 �� 0.1 Ma (1��). Associated dikes intruding the shear zone were also affected by N���S extension resulting in the exhumation of the MCC, which was triggered by the opening of the Pannonian back���arc basin in response to the Carpathian slab���rollback., Plain Language Summary: Horizontal stretching of continental plates induces thinning of the crustal upper part, melting of rocks, the sinking of the land surface, and formation of large basins. One of the world's best���studied basins formed by such a process is the Central European Pannonian Basin. This basin is surrounded by the mountain belts of the Alps, Carpathians, and Dinarides. We have studied rocks between the Pannonian Basin and the southerly adjacent Dinaride Mountains, where rocks deposited in the basin are found right next to rocks that were initially about 7���8 km deep in the crust. These rocks are separated by a shear zone, along which they were brought to the surface. We have dated the activity of the shear zone by measuring concentrations of radioactive isotopes and their decay products contained in deformed minerals. The shear zone was active at a time when the Pannonian Basin started to open due to tectonic processes further NE underneath the Carpathian mountain chain. We also found evidence that the shear zone, which brought metamorphic rocks upwards was formerly one that brought rocks downwards into the crust during an earlier phase of mountain building, predating basin formation., Key Points: Activity along the shear zone exhuming Cer metamorphic core complex in the internal Dinarides was dated by 40Ar/39Ar geochronology to ���17 Ma. Exhumation was facilitated by extensional reactivation of Late Cretaceous���Paleogene nappe contacts resulting from Adria���Europe collision. Extensional reactivation of the thrusts is interpreted as a far���field effect of Oligo���Miocene Carpathian slab rollback.

These files represent the supplementary material to our publication titled Torn between two plates: exhumation of the Cer Massif (internal Dinarides) as a far-field effect of Carpathian slab rollback inferred from 40Ar/39Ar dating and cross section balancing. Dataset 01: Ar-Ar in-situ dating Dataset 02: Ar-Ar single-grain total fusion dating Dataset 03: Ar-Ar single-grain step heating dating Dataset 04: Ar-Ar multi-grain step heating dating Table S2: element oxides obtained by EMPA analyses of Hbl and results of Al-in-Hbl geothermobarometry Figure S01: ranked order plots and inverse isochron plots of SGTF experiements Figure S02: ranked order plots and inverse isochron plots of SGSH experiments

Detailed outcrop-scale analysis of fault-slip data, in combination with data presented on published geological maps, were used for a reconstruction of the structural architecture and tectonic evolution of the Velebit Mt., the most prominent geomorphological structure in the central part of the External Dinarides in Croatia. The analysis of kinematic indicators recorded by major fault planes indicates the prevalence of dip-slip and top-to-NE motions, verifying that these faults are NE-verging thrusts rather than NE-dipping normal faults as previously thought. Consequently, we challenge earlier tectonic models that interpret the Velebit Mt. structure as a SW-vergent antiformal stack or thrust duplex formed above the major NE-dipping thrust system (TARI KOVAČIĆ & MRINJEK, 1994) or as a complex transpressional structure formed during the late-orogenic escape tectonic phase along an inherited crustal fault zone (GRANDIĆ et al., 2004 ; KORBAR, 2009). Instead, we use the concept of a passive roof duplex within a triangle structure. Thereby, the Velebit structure represents a stack of NE-verging backthrusts formed above a SW-vergent compressional duplex. Our interpretation was recently tested by BALLING et al. (2017) by construction of forward modelled balanced cross sections. Additionally, we analysed a large set of fault-slip data comprising more than 1000 measurements collected in the carbonate breccia exposed along the SW mountain slope at about 60 measurement sites. Curiously, the majority of recorded fault-slip data comprise structures with a normal sense of shear indicating orogen-perpendicular (NE-SW) to orogen-parallel (NW-SE) extension. According to the very good preservation and high frequency of occurrence, these extensional structures may have played an important role in formation of the extremely voluminous carbonate breccia exposed along the SW mountain slope. Accordingly, we propose that these structures resulted from a state of stress characterised by radial extension induced by gravitational collapse and spreading as a result of the uptilting of the SW-dipping Velebit monocline. Therefore, our interpretation is only partly in accordance with KORBAR (2009) who suggested that divergent extension and gravity gliding was a major mechanism in formation of the carbonate Jelar breccia in general.

The long-lasting convergence between the European and Adriatic plate led to the formation of the Dinar- ides fold and thrust belt. The Cretaceous deformation of the Internal Dinarides, composed by ophiolite-bar- ing nappes, is older than the mid Eocene deformation of the External Dinarides. The later consists mainly of shallow marine Mesozoic and Cenozoic carbonate platform rocks. Besides the overall younging trend of the start of the deformation from the internal to the external part, the Dinarides show a very prominent NW-SE “Dinaric” strike of the main folds and faults. However, a large-scale dextral strike-slip fault, the Split-Karlovac-Fault (SKF) striking N-S is interrupted this homogenous deformation pattern within the Ex¬ternal Dinarides. Within the most external part, the fault changed its strike to the “Dinaric” NW-SE strike and its kinematics turned to a pure top-SW thrusting. In close proximity to this change of fault kinematics, most of the heterogeneous 2 km thick mid-Eocene to late Oligocene sedimentary sequence is exposed - the Promina Beds. These beds are syn-tectonic and date the latest major deformation event within the Exter¬nal Dinarides and cover older Mesozoic and Cenozoic platform carbonate rocks in a progressive angular unconformity. Former sedimentological studies stated that the Promina Beds show an overall trend from deeper over shallow marine to fluvial depositional conditions, documenting the evolution from an under¬filled to an overfilled basin. The overall tectonic mechanism for the subsiding of the Promina Basin is a matter of debate, whether the accommodation space was created by a subsiding piggyback basin or in a flexural foreland basin setting. To validate one of the both tectonic settings, we have forward- and backward-modeled three balanced cross-sections on both sides of the SKF. Interestingly, the SKF marks a paleo-facies transition from a hiatus in the west to Permian evaporites in the east. The presence vs. absence of Permian evaporites led to areas of a contrasting style of deformation. The deformation in the western non-evaporitic segment of the SKF is characterized by a SW-vergent duplex system, which expands to the NW and is associated with a large- scale NE-vergent back thrust. In contrast, within the eastern segment the evaporites served as a main de¬tachment, which is used to tectonically double the entire carbonate platform by a SW-vergent nappe stack. Our results show, that the complex and contrasting hinterland deformation is related partly to the pres-ence of evaporites, leading to a nappe stack in the eastern segment, which produced a lithosphere flexure and enough subsidence. This favours the flexural foreland basin hypothesis for the origin of the Promina Basin, because most of the present-day outcropping sediments can be solely found in a close proximity to this eastern nappe stack. The Promina Beds solely contain carbonate platform rocks, proving that the catch¬ment did not substantial changed throughout time.

The Dinarides fold-and-thrust belt on the Balkan Peninsula records the long-lasting history of convergence between the European and the Adriatic plates. The Internal Dinarides are composed of composite ophiolite-bearing nappes, whereas the External Dinarides largely consist of Mesozoic and Paleogene shallow marine Adriatic Carbonate Platform (AdCP) rocks. Due to numerous paleontological studies the chronostratigraphic evolution of the AdCP is well known. However, kinematics, timing, and in some places even the geometry of Cenozoic deformation of the AdCP (i. e. the formation of the External Dinarides) are poorly constrained due to the lack of siliciclastic deposits suitable for dating of deformational events/phases. Consequently, neither exhumation rates nor deformation rates based on low-temperature thermochronology are yet known in this part of the Dinarides. However, the presence of different types of syn-depositional and tectonic breccia, in particular those outcropping over large areas on both sides of the Velebit Mts., could help in constraining the timing of Cenozoic deformational events. For this purpose, besides the definition of age and formation mechanisms of these breccia, their structural position is of crucial importance. To show the different structural postions we described the different breccia in the field and integrated them into a kinematic forward model of the Velebit Mts, an up to 1800 m high mountain range along the Adriatic coast. The geologically most viable, kinematically forward modelled cross-section is based on geological maps, dip data, four boreholes, an unpublished cross-section and fault kinematic data ; the latter revealing that the Velebit structure is controlled by a major NE vergent back thrust. In the northwestern part of the Velebit hinterland, a mostly monomict breccia conformably overlaying Jurassic and Cretaceous carbonates is widely exposed. Based on its structural position that is confined to the footwall of the major NE vergent back thrust and its petrographic characteristics, we interpret this breccia to represent tectonically reworked material mostly derived from lithologies in the footwall of the back-thrust. In contrast, the foreland-facing SW slope of the Velebit Mts. is characterised by the presence of mostly polymict breccia, known as Velebit breccia. Taking its structural position and its petrographic composition into account, this breccia is interpreted as consisting of prevailingly talus and fill-up deposits of a flexural foreland basin that formed during late Paleogene times due to the SW advancing nappe stacking. Our kinematic forward model suggests that both the cataclastic and the talus breccia must have formed at the same time, because their formation is directly related to shortening and uplift of the Velebit structure. Additionally, we found two types of much older intraformational breccia: Triassic intraformational breccia located in the hanging wall of Triassic normal faults and Cretaceous intraformational breccia, which is not associated to any local structure and hence only reflects pre-contractional emersion phase(s). Our study underlines that a precise distinction of the structural position and the formation mechanisms of seemingly monotonous, but genetically different carbonate breccia with respect to major km-scale faults and fault-related folds, are crucially important to gain an improved understanding of the kinematics and timing of deformation in carbonate-dominated thrust belt portions.

Mt. Velebit is the most prominent geomorphological structure in the central part of the External Dinarides fold-thrust belt formed by contraction along the eastern margin of the Adriatic plate during Cenozoic convergence between the Adriatic and European plates. Detailed outcrop-scale analysis of fault-slip data were used in evaluation of existing tectonic models, reconstruction of the present-day structural architecture and tectonic evolution of the mountain. Our analysis shows the prevalence of dip-slip and top-to-NE motions along major Velebit’s faults, verifying that these faults are NE-verging thrusts and not NE-dipping normal faults as previously thought. Consequently, we also challenge earlier tectonic models that interpret the Mt. Velebit as a SW-vergent antiformal stack or thrust duplex formed above the major NE-dipping thrust system. Our data rather validate the concept of a passive roof duplex recently tested by Balling et al. (2017) by the construction of forward modelled balanced cross sections. Based on orientation and kinematic compatibility criteria of recorded fault-slip data, we separated six groups of conjugate fault sets used for assessing paleostress directions. Relative chronology between analysed sets and separated groups is partly defined. Presumably the oldest two groups contain fault sets with prevailing dip-slip and reverse motions: a first one is composed of antithetic NNW-striking sets that indicate the ENE–WSW trending contraction ; the second group contains a WNW-dipping set, which indicates WNW-ESE trending contraction. Structures of both groups strike parallel and slightly oblique to the structural grain and the mountain front. They are thus supposed to have formed during the major contractional tectonic phase in this part of the External Dinarides. Most of the recorded fault-slip data comprise structures with a normal sense of shear. These are separated into three groups: the most robust subgroup is composed of NW-striking antithetic fault sets indicating NE-SW trending extension ; a second group comprises NNE-striking antithetic sets, which show WNW–ESE extension, while a third group includes W-striking antithetic sets related to a N–S extension. Although separated into three kinematically homogeneous subgroups, these structures possibly resulted from one and the same state of stress, characterised by radial extension that according to good preservation and frequency of occurrence might play an important role in the formation of extremely voluminous carbonate breccia exposed along the SW slope of the mountain. The remaining group of faults comprises sets of subvertical, conjugate NW-striking dextral and NE-striking sinistral faults, which indicate N–S trending contraction. Outcrop- to map-scale overprinting relationships, suggest these to be the youngest brittle deformation structures in the study area. Acknowledgements. This research was financially supported by the Croatian Science Foundation, Grant no. IP-2014-09-9666. REFERENCES Balling, P., Tomljenović, B., Schmid, S.M., Ustaszewski, K. 2017. Contrasting deformation styles across the Split-Karlovac Fault (External Dinarides) induced by reactivation of pre-existing structures. In: Šarić, K., Prelević, D., Sudar, M. & Cvetković, V. (eds.): 13th Workshop on Alpine Geological Studies, Abstracts, Uni. Belgrade, Belgrade.

The long-lasting convergence between the European, African and Adriatic Plates led to the deformation of the Dinarides fold and thrust belt. This orogen is subdivided into the internal and external Dinarides. The internal part is composed by composite ophiolitic nappes, whereas the external part consists of several thrust sheets of mainly Mesozoic to Paleogene shallow marine Adriatic Carbonate Platform rocks. The presence of Mid-Eocene to Mid-Miocene syntectonic deposits defines the time interval of SW directed folding and thrusting. Here Triassic and Late Cretaceous evaporitic intercalations serve as main detachment horizons in the external Dinarides, resulting in a NW-SE strike, which can be traced from Slovenia to Albania. However, the exact amount of total shortening and its Neogene component is unknown. To tackle this issue we balanced two unpublished cross-sections across external Dinarides. Furthermore, we investigated several Miocene wedge-top basins with respect to their substratum. These restricted intra-montane basins were filled with up to 500 m of lacustrine limestones. Field observations show that these basins are not fault bounded and passively uplifted by much deeper faults. This is supported by the analysis of longitudinal river profiles, which show that major knickpoints in this area are immobile and are hence rather related to erosional contrast between different lithologies. This, in turn, implies that the basin boundaries underwent insignificant deformation. Our balanced sections strongly support the assumption that the total amount of shortening within the study area is highly variable alongstrike. In the northern profile we assessed a total shortening of ~60 km (38%), whereas in the southern profile a minimum shortening of ~130 km (88%) was estimated. The high variation of shortening amounts is strongly affected by the presence of a largescale dextral transpressive strike-slip fault, the Split-Karlovac Fault. This fault also seems to actively accommodate seismogenic strain. This is suggested by the pronounced seismic moment release that spatially coincides with the SE end of the Split-Karlovac Fault. The fact that the great majority of earthquakes along the southern profile show reverse faulting mechanisms, implies that the strain field remained unchanged since the onset of folding and thrusting in Paleogene times.

International audience; Sedimentary basins in the interior of orogenic plateaus can provide unique insights into the early history of plateau evolution and related geodynamic processes. The northern sectors of the Iranian Plateau of the Arabia–Eurasia collision zone offer the unique possibility to study middle–late Miocene terrestrial clastic and volcaniclastic sediments that allow assessing the nascent stages of collisional plateau formation. In particular, these sedimentary archives allow investigating several debated and poorly understood issues associated with the long-term evolution of the Iranian Plateau, including the regional spatio-temporal characteristics of sedimentation and deformation and the mechanisms of plateau growth. We document that middle–late Miocene crustal shortening and thickening processes led to the growth of a basement-cored range (Takab Range Complex) in the interior of the plateau. This triggered the development of a foreland-basin (Great Pari Basin) to the east between 16.5 and 10.7 Ma. By 10.7 Ma, a fast progradation of conglomerates over the foreland strata occurred, most likely during a decrease in flexural subsidence triggered by rock uplift along an intraforeland basement-cored range (Mahneshan Range Complex). This was in turn followed by the final incorporation of the foreland deposits into the orogenic system and ensuing compartmentalization of the formerly contiguous foreland into several intermontane basins. Overall, our data suggest that shortening and thickening processes led to the outward and vertical growth of the northern sectors of the Iranian Plateau starting from the middle Miocene. This implies that mantle-flow processes may have had a limited contribution toward building the Iranian Plateau in NW Iran.