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The complete evolutionary process of orogenesis can be deciphered by studying metamorphic rocks at middle and lower crustal depths of orogens. Recent studies have suggested that granulite-facies metamorphic rocks in the Paleoproterozoic Jiao–Liao–Ji orogenic belt experienced clockwise pressure–temperature (p–T) paths. However, due to the effects of high temperature, the prograde metamorphic processes are poorly constrained. The question could be solved by studying the Barrovian series rocks, because some garnet growth zoning has been preserved in the lower grade rocks. A Barrovian series from garnet to kyanite-sillimanite zones has been recognized in the Liaodong Peninsula. Based on petrology and mineral chemistry, each metamorphic rocks in metamorphic zone are divided into prograde, peak, and retrograde metamorphic stages. Pseudosection modelling constrains the peak metamorphic conditions at ~568°C and ~5.8 kbar for the garnet zone, ~585°C and ~6 kbar for the staurolite zone, and ~670°C and ~8.2 kbar for the kyanite-sillimanite zone. All Barrovian series rocks have clockwise p–T paths, implying crustal thickening during prograde metamorphism. LA-ICP-MS monazite and zircon U–Pb dating suggest that peak Barrovian metamorphism occurred at ca. 1.92–1.91 Ga. Combining our results of the Barrovian series with studies on granulite-facies metamorphic rocks, we suggest that the Jiao–Liao–Ji belt experienced crustal thickening from 1.95 to 1.90 Ga, inducing Barrovian metamorphism and granulite-facies metamorphism in the middle and lower crust, respectively. Subsequently, rocks located at the different crustal levels were exhumed during post-orogenic extension. [ABSTRACT FROM AUTHOR]

Thermobarometry in the Northern Snake Range metamorphic core complex (Nevada, USA) implies pre‐extensional burial of footwall rocks to 21–30 km depths, while geologic field relationships support 7–13 km pre‐extensional depths. This has fueled a 40‐year‐long debate, which has far‐reaching implications for how pressure data are interpreted in orogenic settings. Here, we test published models for deep burial by integrating regional cross‐section reconstructions with new (n = 95) and published (n = 132) peak temperature measurements, field relationships and published geophysical data. Burial of Neoproterozoic‐Cambrian metasedimentary footwall rocks to 21–30 km depths is incompatible with a regional seismic reflection cross‐section that interprets the top of Precambrian crystalline basement at 17–20 km depths. Two reconstructed cross‐sections define 42 km and 50–65 km of displacement on the master detachment fault and demonstrate that the higher displacement ranges (>66–94 km and >76–102 km, respectively) necessary to exhume rocks from 21 to 30 km depths are not possible without spatially overlapping Cambrian rocks preserved in its footwall and hanging wall. The 22°C/km average Late Cretaceous thermal gradient predicted by thermobarometry is incompatible with the 46 ± 10°C/km Late Cretaceous peak thermal gradient that we calculate down to 15–20 km pre‐extensional depths. Field relationships that rule out large‐magnitude shortening invalidate models for deep footwall burial via thrust or reverse faulting. We conclude that there is no scenario for deep burial that is compatible with structural/geophysical constraints, crustal thermal architecture, and field relationships. This necessitates a non‐lithostatic interpretation for pressures from the Northern Snake Range, similar to recent interpretations for other Cordilleran metamorphic core complexes. Key Points: Strain compatibility demonstrates that the detachment displacement necessary to exhume footwall rocks from 21 to 30 km depths is not possibleThe 22°C/km gradient predicted by thermobarometry is incompatible with the Late Cretaceous thermal gradient of 46 ± 10°C/km that we calculateA non‐lithostatic interpretation for pressure data from the Northern Snake Range is required, similar to other Cordilleran core complexes [ABSTRACT FROM AUTHOR]

[Display omitted] • A regional geology systematic review based on cross-sections and space–time diagrams. • The Dom Feliciano Belt orogenic cycle records pre-, syn- and post-collisional stages. • PT-paths are characteristic of hinterland and foreland tectonic domains. • Northern DFB foreland rifting contrasts with central DFB active margin in the Tonian. • The symmetric schismogenesis of West Gondwana Orogen models can be conciliated. The Dom Feliciano Belt evolution is reviewed based on cross-sections, space–time diagrams, P-T paths, and Sr–Nd isotopic data of pre-collisional metaigneous rocks. The belt is divided into northern, central and southern sectors, subdivided into tectonic domains, developed at Neoproterozoic pre-, syn- and post-collisional stages. The northern sector foreland pre-collisional setting represents a rift, with tholeiitic (meta)volcanic rocks (∼800 Ma) chronocorrelated to hinterland intermediate and acidic orthogneisses of high-K calc-alkaline arc signature. In contrast, the central sector records a complete section from the forearc towards the back-arc region during pre-collisional times. In the western domain, ophiolites (∼920 Ma) are associated with arc-related orthogneisses and metavolcanic rocks (880–830 Ma; 760–730 Ma). At back-arc position, continental arc-related magmatism (800–780 Ma) is registered by hinterland orthogneisses and central foreland metavolcanic rocks. Ophiolites on the hinterland opposite side comprise two compositional groups, with N-MORB and supra subduction signature, interpreted as a back-arc basin record (∼750 Ma). The pre-Neoproterozoic basement of the whole belt is correlated with the Nico Perez Terrane and Luis Alves Block (Archean to Mesoproterozoic, with Congo Craton affinity). This contrasts with the Piedra Alta Terrane (Rio de La Plata Craton, only Paleoproterozoic), westernmost Uruguay. The suture between the Piedra Alta and Nico Perez terranes is correlated with the suture zone in the westernmost central sector. Transpression affected both foreland and hinterland during collision (660–640 Ma), with high-T/low-P hinterland progressive exhumation, whilst foreland low- to medium-grade correlated sequences record underthrusting. Post-collisional processes included magmatism throughout the belt (640–580 Ma), strain partitioning along strike-slip shear zones, and foreland basin fill. Late tectono-metamorphic and magmatic processes (560–540 Ma) were attributed to the Kalahari Craton collision. Arc magmatism migration due to subduction angle variations suggests modern-style plate tectonics during Gondwana amalgamation. Diachronism and kinematic inversion are characteristic of an oblique convergent multi-plate orogenic system. [ABSTRACT FROM AUTHOR]

Lithospheric foundering is hypothesized to contribute to the formation of Earth's largest continental plateaus, but the predicted effects remain poorly constrained, especially considering variations in crustal strength. Here we propose that lithospheric foundering involving a hot, weak crust can explain aspects of topography and crustal deformation in mountain belts. We explore this hypothesis using numerical models of orogenesis and foundering in the Southern Puna Plateau in the Central Andes. Contrary to previous models of foundering involving a strong crust, which are characterized by subsidence and shortening, a weak crust results in surface uplift and upper‐crustal horizontal extension, which is accommodated by horizontal shortening in peripheral regions. Our model explains data such as the timing and location of exhumation and basin sedimentation as a response to foundering. The model also shows that foundering is capable of converting a high‐relief, broken‐foreland region into a high‐elevation, low‐relief plateau in a convergent tectonic setting. Plain Language Summary: Thickened crust can gravitationally unstable and founder into the mantle. This process could contribute to the formation of large plateaus such as Tibet and the Central Andes, which are composed of hot, felsic, and therefore weak crust. However, existing models have not thoroughly considered the implications of lithospheric foundering beneath a weak crust. We present numerical modeling experiments that show that a lithospheric drip can cause crustal flow and spreading, even when it takes place within a convergent tectonic setting, such as a major mountain belt. By comparing our models to geologic data from the Central Andes, we suggest that this scenario can explain many intriguing geological puzzles within the Puna Plateau, such as the timing and distribution of horizontal extension, the thickening of the crust, and the uplift history of the plateau. Future studies should consider the possibility of a weak, flowing crust during a lithospheric foundering event. Key Points: Lithospheric foundering under a hot, weak crust causes syn‐convergent, upper‐crustal extensionOur models successfully explain the Cenozoic uplift and deformation of the Puna Plateau as a result of this processThis style of foundering has been overlooked but may apply to other large orogens [ABSTRACT FROM AUTHOR]

Structural elements of the Svecokarelide pericratonic zone in the Karelian Massif (SE Fennoscandia) were identified and described. They were formed after the major events of the Svecofennian tectogenesis. The age ranges of the orogenic stage and the post-orogenic extension collapse were dated, and the depth levels of the corresponding structures were determined. The differentiated exhumation process of deep complexes of the post-Proterozoic Savo–Ladoga movable zone was visualized. The approximate exhumation velocities of the deep material were estimated at certain stages of Precambrian evolution in the zone under consideration. [ABSTRACT FROM AUTHOR]

The Porgera Transfer Zone (PTZ) is a major crustal and probably lithospheric structure across Papua New Guinea recording >50 km offset of ophiolites and very different patterns of geology and topography on either side. In the Late Jurassic, the PTZ probably separated oceanic crust and thick Jurassic Om shales to the west from a continental promontory to the east. During the Late Miocene to Recent orogenesis, the differential compression of these features is interpreted to have created a dextral strike slip fault across the fold belt with pull-apart basins at sites of fault relays. This facilitated the ascent of intrusions and mineralization at Porgera. The acquisition of high-resolution LIDAR data semi-regionally around the Porgera Gold Mine greatly improved interpretation of the regional geology and particularly the recognition of normal faults. By correlating with sparse dip data and paly-dated samples, it was possible to create stratigraphic sections and interpret structural cross-sections using the LIDAR data. As the area involved strike–slip offsets, it was important to construct sections in multiple orientations in order to interpret the 3D geology. Both dips and fault orientation could be directly inferred from the LIDAR data such that sections could be constructed orthogonally to them. A balanced, restored and forward-modelled cross-section illustrates the interaction between thrust faults and normal faults during compression and that it was synchronous with the development of a pull-apart basin. A semi-regional 3D geological model, which was developed mainly from the LIDAR data, supports the hypothesis of inversion of the thick Om beds to the west before or during compression of the continental promontory to the east resulting in dextral strike–slip offsets across the PTZ. A jog or relay in the faults occurred and caused a pull-apart collapse basin to develop in the area of the Porgera mine. Similar pull-apart graben, or negative flower structures, were detected nearby and may be areas for future exploration. [ABSTRACT FROM AUTHOR]

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Continental orogens that involve subduction and collision are important target areas for studying the growth, stabilization and transformation of Earth's continents. In particular, the nature of the lithospheric mantle and its relationship to the overlying crust in these active subduction-collision zones are key factors to be constrained. Mantle xenoliths entrained by Cenozoic basalts from the Indochina Block, the Sukhothai Arc and the Inthanon Zone (IB-SA-IZ) provide direct deep-seated samples of the lithospheric mantle derived from part of the Tethyan orogenic belt, offering a unique opportunity to study mantle processes during orogenesis in response to the closure of the Paleo-Tethys Ocean. The studied mantle xenoliths comprise 32 spinel lherzolites, six harzburgites, and one olivine websterite. We present a comprehensive study of the elemental geochemistry and Os isotopes of this sample suite. Their lithophile element systematics indicate that they represent mantle residues after varying degrees of melt extraction (5–24%), followed by melt refertilization. Although the highly siderophile element abundances have been affected to some extent by melt refertilization through removal of sulfides, the Os isotopic compositions of the studied xenoliths were minimally disturbed. Lherzolites and the sole olivine websterite from the IB-SA-IZ share similar Re-Os isotope systematics (187Os/188Os: 0.121–0.137) to global abyssal peridotites, representing juvenile lithospheric mantle accreted from the upwelling asthenosphere, most likely associated with arc-continent collision in response to the closure of the Paleo-Tethys Ocean and back-arc basin during the Middle-Late Triassic. In contrast, the refractory harzburgites from the Indochina Block and Sukhothai Arc are characterized by substantially lower 187Os/188Os ratios (187Os/188Os: 0.117–0.122) than the lherzolites, yielding Mesoproterozoic Re-depletion Os model ages, which can be interpreted as either ancient lithosphere relics beneath these regions or accreted ancient mantle debris from the upwelling asthenosphere. Although the interpretation for the origin of the older harzburgites is ambiguous, we can conclude that rejuvenation of the lithospheric mantle commonly occurred beneath different tectonic units of the Tethyan orogenic belt: i.e., the pre-existing lithospheric mantle beneath different tectonic units of the Tethyan orogenic belt has been largely replaced by upwelling asthenospheric mantle during the Middle-Late Triassic orogenesis. This mantle was then further refertilized to varying degrees by asthenosphere-derived melts. Both processes play key roles in defining the nature of the lithospheric mantle in orogenic settings. This study also highlights that the geodynamic processes in the lithospheric mantle beneath orogenic belts can be well constrained by integrated evidence from lithophile and highly siderophile elements and their isotopes (e.g., Os isotopes) of mantle xenoliths. [ABSTRACT FROM AUTHOR]

Abstract Lithospheric foundering is hypothesized to contribute to the formation of Earth's largest continental plateaus, but the predicted effects remain poorly constrained, especially considering variations in crustal strength. Here we propose that lithospheric foundering involving a hot, weak crust can explain aspects of topography and crustal deformation in mountain belts. We explore this hypothesis using numerical models of orogenesis and foundering in the Southern Puna Plateau in the Central Andes. Contrary to previous models of foundering involving a strong crust, which are characterized by subsidence and shortening, a weak crust results in surface uplift and upper‐crustal horizontal extension, which is accommodated by horizontal shortening in peripheral regions. Our model explains data such as the timing and location of exhumation and basin sedimentation as a response to foundering. The model also shows that foundering is capable of converting a high‐relief, broken‐foreland region into a high‐elevation, low‐relief plateau in a convergent tectonic setting.

By demonstrating that extensional inheritance plays a decisive role in the formation of orogens, recent studies have questioned the ability of a unique, complete Wilson cycle model to explain the diversity of collisional orogens. For 5 years, the OROGEN Research Project had therefore the ambition to challenge this classical Wilson cycle model. By focusing on the diffuse Africa-Europe plate boundary in the Biscay-Pyrenean-Western Mediterranean system, the project questioned the preconceived “Orogen singularity” assumption and investigated the role of divergent and convergent maturities in orogenic and post-orogenic processes. This work led us to rethink the development of collisional orogens in a genetic (or process-driven) way and to propose an updated version of the ” classical Wilson cycle”, the Wilson Cycle 2.0, and the ORO-Genic ID concept presented in this paper. The particularity of the Wilson Cycle 2.0 is to take into account the divergence and convergence maturity reached during extensional and orogenic processes in proposing different tectonic tracks associated with different ORO-Genic ID numbers. The ORO-Genic ID is composed of a letter (or track), corresponding to the maturity of divergence reached and a number corresponding to the maturity of convergence reached during the formation of the orogen. This new concept relies on the observed pre- and syn- convergent tectono- stratigraphic and magmatic record and deformation history and can be identified in using diagnostic criteria presented in this paper. It represents therefore a powerful tool that can be used to characterize the evolution and the architectural type of an orogenic system. Moreover, as a mappable concept, it can be easily used worldwide and can help us to explain differences in the style of deformation at crustal scale between orogens.

The Porgera Transfer Zone (PTZ) is a major crustal and probably lithospheric structure across Papua New Guinea recording >50 km offset of ophiolites and very different patterns of geology and topography on either side. In the Late Jurassic, the PTZ probably separated oceanic crust and thick Jurassic Om shales to the west from a continental promontory to the east. During the Late Miocene to Recent orogenesis, the differential compression of these features is interpreted to have created a dextral strike slip fault across the fold belt with pull-apart basins at sites of fault relays. This facilitated the ascent of intrusions and mineralization at Porgera. The acquisition of high-resolution LIDAR data semi-regionally around the Porgera Gold Mine greatly improved interpretation of the regional geology and particularly the recognition of normal faults. By correlating with sparse dip data and paly-dated samples, it was possible to create stratigraphic sections and interpret structural cross-sections using the LIDAR data. As the area involved strike–slip offsets, it was important to construct sections in multiple orientations in order to interpret the 3D geology. Both dips and fault orientation could be directly inferred from the LIDAR data such that sections could be constructed orthogonally to them. A balanced, restored and forward-modelled cross-section illustrates the interaction between thrust faults and normal faults during compression and that it was synchronous with the development of a pull-apart basin. A semi-regional 3D geological model, which was developed mainly from the LIDAR data, supports the hypothesis of inversion of the thick Om beds to the west before or during compression of the continental promontory to the east resulting in dextral strike–slip offsets across the PTZ. A jog or relay in the faults occurred and caused a pull-apart collapse basin to develop in the area of the Porgera mine. Similar pull-apart graben, or negative flower structures, were detected nearby and may be areas for future exploration.

Cordilleran orogens are complex tectonic systems, strongly influenced by lithospheric deformation and exhumation. However, in the type region of the Central Andes, the timing and mechanisms of deformation and mountain building remain poorly constrained, especially for the high‐elevation Puna Plateau of NW Argentina. We use geologic mapping, structural cross‐sections, low‐temperature thermochronology, and U‐Pb dating of ash and detrital zircons to elucidate the history and style of orogenic deformation in the Antofalla region of the Puna Plateau. Cooling ages of major reverse fault hanging walls and dated growth strata indicate that crustal shortening activated major reverse faults during the Eocene and continued out‐of‐sequence through the Early Miocene. This protracted period of shortening, which resulted in the filling of the Antofalla Basin, was followed by a transient episode of upper‐crustal E‐W extension on a major normal fault system during the Late Miocene. Pliocene to Quaternary time saw E‐W shortening return to the region. Our structural cross‐section permits only a low magnitude of shortening (∼15–25%), which stands in contrast to the 60‐km thick crust. Triassic to Cretaceous cooling ages from footwall rocks and minor structures indicate that the entire region experienced little exhumation or sedimentation during the Mesozoic, perhaps retaining a crust thickened during multiple episodes of Paleozoic orogenesis. The crust may also reflect lower‐crustal thickening due to the growth of a lithospheric drip during the Late Miocene. Key Points: Combination of structural mapping, thermochronology, and U‐Pb chronostratigraphy reveals four phases of Cenozoic deformationExhumation due to horizontal shortening was underway by the Eocene (∼45 Ma), ∼20 Myr earlier than previously inferred for the regionShortening propagated out‐of‐sequence, westward from the Calalaste Range into the Antofalla Basin until ∼15 Ma [ABSTRACT FROM AUTHOR]

Four Tethyan ocean basins are recognised in Asia, the Proto-Tethys (Late Proterozoic - Silurian), Palaeo-Tethys (Middle Devonian - Late Triassic), Meso-Tethys (Middle Permian - Late Cretaceous) and Ceno-Tethys (late Middle Triassic - Eocene). Multi-disciplinary data, including ages of pelagic sediments, ocean plate stratigraphy, seamounts, ophiolites, blueschists, eclogites in accretionary complexes, volcanic arc and magmatic rocks found along suture zones of the Tethyan oceans are described and used to date the opening and closure of these oceans. The evolution of the Tethyan ocean basins in Asia illustrates that Asia has been a giant convergent zone for more than 500 million years and the Phanerozoic construction and evolution of Asia involved the opening and closure of Tethyan ocean basins and the collision and accretion of Gondwana-derived continental blocks and the Indian Craton. Subduction processes, arc and back-arc basin generation, and continent-continent and arc-continent collisions led to the principal orogenic events, basin development and related mineral and energy resource deposits recorded in Asia. Three major orogenic belts are recognised in Asia, the Central Asian Orogenic Belt, that relates to the evolution of the Palaeo-Asia Ocean, and the Tethyan (Tethysides) Orogenic Belt and the Alpine-Himalayan Orogenic Belt which relate to the evolution of Tethyan ocean basins. The principal Tethyan basin related orogenies in Asia are the Bhimphedian Orogeny (Ordovician-Silurian) that reflects the collision of major Asian continental blocks ("Asian-Hun Superterrane") with Gondwana, the Indosinian (Cimmerian) Orogeny (Permian-Triassic) resulting from Palaeo-Tethyan subduction processes, collisions of Asian blocks and collision of the Cimmerian continent with Asia, and the Himalayan-Tibetan Orogeny (Cretaceous-Palaeogene) caused by subduction of the Meso- and Ceno-Tethys oceans and the Lhasa-Asia and India-Asia collisions. [Display omitted] • Proto-, Palaeo-, Meso-, and Ceno-Tethys oceans are recognised in Asia. • Orogeny was driven by subduction/closure of Tethyan oceans and collision of blocks. • Tethyan & Alpine-Himalayan orogenic belts relate to evolution of Tethyan oceans. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three phases of deformation (D 1 -D 3) are recognized in the Langzishan Barrovian metamorphic series. • The kyanite zone rocks record a clockwise P-T-D path in the Paleoproterozoic. • Metamorphic and deformational characteristics documented by Barrovian metamorphic series in the Paleoproterozoic and Phanerozoic are comparable, possibly indicating a similar orogenic mechanism. Orogenesis always involves multiple tectonic events accompanied by metamorphic cycles. The Barrovian metamorphic series often records complicated prograde metamorphism and deformational features, which are crucial for understanding the related orogenic evolution. While Barrovian metamorphism have been widely documented in the Phanerozoic orogenic belts, limited stuides have been conducted on Paleoproterozoic Barrovian metamorphic series. In this contribution, Barrovian metamorphic series extending from biotite to kyanite zones in the middle of Jiao-Liao-Ji Orogenic Belt (JLJOB) from eastern part of North China Craton (NCC) was investigated. The current studies identified the occurrence of polyphase deformation and metamorphism within the Langzishan Barrovian metamorphic series. D 1 fabrics are characterized by the development of S 1 foliation and L 1 lineation in association with greenschist facies metamorphism (M 1) that occurrs at ca. 490 ℃ and ca. 5.7 kbar. D 2 fabrics that include different folds (F 2), S 2 crenulation cleavage, S 2 foliation and L 2 lineation, accompanied by the low amphibolite metamorphism (M 2) that occurrs at ca. 670 ℃ and 8.2–8.6 kbar. D 3 fabrics involving kink band postdate sillimanite growth that occurrs at ca. 660 ℃ and ca. 6.5 kbar, and predate chlorite occurrence. Monazite U-Pb dating suggests the peak and retrograde metamorphic ages of ca. 1.93 Ga and 1.86 Ga, respectively. Thus, a clockwise pressure–temperature-time-deformation (P-T-t-D) path is established, possibly related to the crustal thickening process. These features are very similar to those documented in Phanerozoic Barrovian metamorphic series, suggesting that a comparable orogenesis mechanism could be shared in the Paleoproterozoic and Phanerozoic. [ABSTRACT FROM AUTHOR]

The assembly and dispersion of continental crust are first-order controls on paleogeography and geochemical cycles. The associated reworking of Earth's crust can be tracked with zircon initial hafnium (ε Hf T) through space and time. Here we apply a new method of quantitative analysis using ε Hf T density estimates based on a compilation of 155,329 ε Hf T values. Investigation of the global database reveals significant geographic and temporal bias in the ε Hf T record associated with sampling and regional tectonic events. Recent research has attempted to address global ε Hf T bias using resampling methods to augment gaps of low ε Hf T data density, which in turn obfuscates tectonic signals and artificially weights outliers. Instead, we evaluate ε Hf T density patterns for both igneous and detrital zircon on eight continental zones demarcated by Paleozoic sutures: Africa, Antarctica, Asia, Australia, Baltica, North America, Peri-Gondwana, and South America. Pairwise two-dimensional quantitative comparison highlights similarity in timing and ε Hf T values between zones, all of which can be linked to documented shared regional tectonism. Integration of all pairwise comparisons reveals that peak similarity corresponds to the timing of supercontinent amalgamation, and that the associated ε Hf T differs depending on the style of supercontinent amalgamation, particularly internal versus external orogenesis. The three most recent supercontinents produced distinctive ε Hf T signals, shared by the constituent continental zones. The supercontinents Rodinia and Pangea were constructed through collisions of marginal arc terranes, peripheral to ancient crust, and did not produce highly enriched ε Hf T values. In contrast, Ediacaran to Cambrian formation of the Gondwana supercontinent was largely the product of internal Pan-African orogens that formed directly after Neoproterozoic Rodinia rifting and arc accretion forming the Arabian Shield. The final assembly of Gondwana was dominated by continent-continent collisions of old radiogenic crust without establishment and accretion of extensive intervening depleted arc terranes, resulting in a more enriched distribution of ε Hf T values compared to prior and subsequent supercontinent formation. The secular ε Hf T record is the product of spatiotemporally biased sampling and preservation of specific orogenic belts with predictable ε Hf T data arrays, modulated by the amalgamation, tenure, and breakup of supercontinents through time. • Zircon Hf is predictable based on tectonic context. • Global Hf records are geographically and temporally biased. • All major Hf excursions can be linked to regional orogenic events. • Zircon Hf is modulated by the amalgamation, tenure, and breakup of supercontinents. [ABSTRACT FROM AUTHOR]

The India-Asia collision zone is the archetype to calibrate geological responses to continent-continent collision, but hosts a paradox: there is no orogen-wide geological record of oceanic subduction after initial collision around 60-55 Ma, yet thousands of kilometers of post-collisional subduction occurred before the arrival of unsubductable continental lithosphere that currently horizontally underlies Tibet. Kinematically restoring incipient horizontal underthrusting accurately predicts geologically estimated diachronous slab break-off, unlocking the Miocene of Himalaya-Tibet as a natural laboratory for unsubductable lithosphere convergence. Additionally, three endmember paleogeographic scenarios exist with different predictions for the nature of post-collisional subducted lithosphere but each is defended and challenged based on similar data types. This paper attempts at breaking through this impasse by identifying how the three paleogeographic scenarios each challenge paradigms in geodynamics, orogenesis, magmatism or paleogeographic reconstruction and identify opportunities for methodological advances in paleomagnetism, sediment provenance analysis, and seismology to conclusively constrain Greater Indian paleogeography., (© The Author(s) 2022. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

New fieldwork and tectonic analysis has been carried out along the Andean morphotectonic frontline between 46°30' and 47°30′S. The right lateral transtensional Marques–Zeballos Pass fault system (MZPRS) controlled the 800–1200 m uplift of the Andes at 16.1–18.1 Ma. Our data and analysis indicate that there was no lower Miocene contractile event along the Andean morphotectonic frontline. The Main Andean Thrust (MAT), which is deeply rooted in the upper crust is a retroarc thrust dipping 10–15° westward, and provides evidence for major crustal shortening at ~120 Ma. At that time the arc volcanic strata of the Ibañez Fm (148–178 Ma) was transported eastward above the rift volcanic Quemado Fm (144179 Ma), which lies unconformably on the Deseado basement massif. The geologic records from the fieldwork together with the available data allow us to identify the processes controlling the dynamic evolution of the two main topographic features of the studied Andean segment. (1) Upward convection originating from the subducted South Chile Ridge −1 segment (SCR −1) is dynamically sustaining the high topography of the North Patagonian Icefield (4070 m at the Mt. San Valentin, ~2 km higher than the Southern South Volcanic Zone). This, together with the locus of maximum moisture being at 47°S during glacial events has resulted in producing the two largest glacial lobes of Patagonia. (2) The 180 km long, E –W trending antiformal arch structure of the Mt. Zeballos Ridge (MZR, a hinge zone trending N–S along the MZPRS) straddling the Andes and the Foreland is proposed to be the morphological "twin" of the South American Plate Moho Plateau (SAM MOHO P). The SAM MOHO P controls the location of both the MZPRS and the MZR boundaries location through time. The Patagonia Slab Window and SAM asthenospheric dynamics (upward and corner flows, respectively) and their in–depth interaction appear to control the morphotectonic evolution of the whole studied segment through a powerful feedback loop between tectonics, morphology, and climate, at least for the past 3–4 Myr. [ABSTRACT FROM AUTHOR]