Subduction and Slab Detachment Under Moving Trenches During Ongoing India-Asia Convergence

The dynamics of slab detachment and associated geological fingerprints have been inferred from various numerical and analog models. These invariably use a setup with slab-pull-driven convergence in which a slab detaches below a mantle-stationary trench after the arrest of plate convergence due to arrival of continental lithosphere. In contrast, geological reconstructions show that post-detachment plate convergence is common and that trenches and sutures are rarely mantle-stationary during detachment. Here, we identify the more realistic kinematic context of slab detachment using the example of the India-Asia convergent system. We first show that only the India and Himalayas slabs (from India's northern margin) and the Carlsberg slab (from the western margin) unequivocally detached from Indian lithosphere. Several other slabs below the Indian Ocean do not require a Neotethyan origin and may be of Mesotethys and Paleotethys origin. Additionally, the still-connected slabs are being dragged together with the Indian plate forward (Hindu Kush) or sideways (Burma, Chaman) through the mantle. We show that Indian slab detachment occurred at moving trenches during ongoing plate convergence, providing more realistic geodynamic conditions for use in future numerical and analog experiments. We identify that the actively detaching Hindu Kush slab is a type-example of this setting, whilst a 25–13 Ma phase of shallow detachment of the Himalayas slab, here reconstructed from plate kinematics and tomography, agrees well with independent, published geological estimates from the Himalayas orogen of slab detachment. The Sulaiman Ranges of Pakistan may hold the geological signatures of detachment of the laterally dragged Carlsberg slab

The forearc ophiolites of California formed during trench-parallel spreading: Kinematic reconstruction of the western USA Cordillera since the Jurassic

Ophiolites, fragments of oceanic lithosphere exposed on land, are typically found as isolated klippen in intensely deformed fold-thrust belts spanning hundreds to thousands of kilometers along-strike. Ophiolites whose geochemistry indicates that they formed above subduction zones, may have been relics of larger, once-coherent, oceanic lithosphere tracts that formed the leading edge of an upper plate below which subduction occurred; such tracts were subsequently dismembered by deformation and erosion during orogenesis and uplift. However, to what extent the first-order original coherence is maintained between ophiolitic klippen is difficult to assess. Here, we aim to evaluate whether the Jurassic forearc ophiolites overlying subduction complex rocks in California, now scattered over 1000 km and dismembered by the wider San Andreas Fault Zone, still maintain their original lithospheric coherence. To this end we (i) compile available crustal ages from all ophiolite klippen exposed in the Jurassic ophiolite belt of the western United States; (ii) review and kinematically reconstruct post-middle Jurassic deformation that occurred between the modern western coast and the stable North American craton to restore the original positions of the ophiolite fragments relative to each other and to North America, and (iii) perform a paleomagnetic analysis of a sheeted dyke sections of the Mt. Diablo and Josephine ophiolites to estimate the orientation of the spreading axis at which the Jurassic Californian forearc ophiolites formed. The latter analysis reveals that the original ridge orientation likely trended ∼080–260°, near-perpendicular to the orientation of the trench along the western margin of the ophiolite belt. We show that with these constraints, a straightforward ridge-transform system can explain the age distributions of the ophiolites with spreading rates of 6–7 cm/a. Our analysis shows that the Jurassic ophiolites of California may be considered klippen of a single sheet of oceanic lithosphere that accreted at a supra-subduction zone spreading ridge. In addition, we show that kinematic and paleomagnetic analysis of ophiolite belts may provide novel constraints on the kinematic evolution of accretionary orogens and the plates now lost to subduction

A global apparent polar wander path for the last 320 Ma calculated from site-level paleomagnetic data

Apparent polar wander paths (APWPs) calculated from paleomagnetic data describe the motion of tectonic plates relative to the Earth's rotation axis through geological time, providing a quantitative paleogeographic framework for studying the evolution of Earth's interior, surface, and atmosphere. Previous APWPs were typically calculated from collections of paleomagnetic poles, with each pole computed from collections of paleomagnetic sites, and each site representing a spot reading of the paleomagnetic field. It was recently shown that the choice of how sites are distributed over poles strongly determines the confidence region around APWPs and possibly the APWP itself, and that the number of paleomagnetic data used to compute a single paleomagnetic pole varies widely and is essentially arbitrary. Here, we use a recently proposed method to overcome this problem and provide a new global APWP for the last 320 million years that is calculated from simulated site-level paleomagnetic data instead of from paleopoles, in which spatial and temporal uncertainties of the original datasets are incorporated. We provide an updated global paleomagnetic database scrutinized against quantitative, stringent quality criteria, and use an updated global plate motion model. The new global APWP follows the same trend as the most recent pole-based APWP but has smaller uncertainties. This demonstrates that the first-order geometry of the global APWP is robust and reproducible. Moreover, we find that previously identified peaks in APW rate disappear when calculating the APWP from site-level data and correcting for a temporal bias in the underlying data. Finally, we show that a higher-resolution global APWP frame may be determined for time intervals with high data density, but that this is not yet feasible for the entire 320–0 Ma time span. Calculating polar wander from site-level data provides opportunities to significantly improve the quality and resolution of the global APWP by collecting large and well-dated paleomagnetic datasets from stable plate interiors, which may contribute to solving detailed Earth scientific problems that rely on a paleomagnetic reference frame

Investigation and Mapping of Active Faults in Antakya and Its Surroundings

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Avrasya Yer Bilimleri Enstitüsü, 2011Thesis (M.Sc.) -- İstanbul Technical University, Eurasia Institute of Earth Sciences, 2011Bu çalışma kapsamında, jeolojik ve jeofizik yöntemler kullanılarak Antakya ve çevresinde etkili olan faylar ve geometrileri araştırılmış, bu fayların bölge morfolojisindeki etkileri incelenmiştir. Bu kapsamda öncelikle uydu görüntüleri ve sayısal arazi verileri kullanılarak morfolojik analizler yapılmış ardından saha çalışmalarında tektonik yapılar gözlemlenerek ölçümler alınmış ve haritalanmıştır. Belirlenen faylar yapısal jeoloji ve jeomorfoloji ağırlıklı, jeofizik destekli çalışmalar ile değerlendirilmiş ve aktiviteleri yorumlanmıştır. Çalışmada, Pliyo-Kuvaterner yaşlı çökeller, kırık sistemleri, depremlerle oluşan yüzey kırığı ile morfotektonik elemanlar detaylı olarak haritalanmıştır. Ayrıca, Antakya ve çevresindeki aktif fayların Yer Radarı (GPR) metodu kullanılarak incelenip bölgenin aktif tektoniğini araştırılmıştır. Jeolojik değerlendirmeler sonucunda graben içinde yanal atımlı ve düşey atımlı iki sistemin egemen olduğunu göstermiştir. Düşey atımlı faylar grabeni oluşturan faylar olarak nitelendirilirken Pliyosen ve Miyosen birimleri kesen yanal atımlı faylar aktif faylar olarak yorumlanmışlardır. Ancak kesin olarak bu faylanmaların ne zaman olduğuna dair veri elde edilememiştir. Yer Radarı ile toplamda 66 profil ölçüm alınmıştır. Aktif olduğu düşünülen Çöğürlü ve Sutaşı faylarının bölgedeki uzanımı incelenmiştir. Değerlendirmeler sonucunda basamaklı bir yapıda olan Sutaşı fayının GB'sına ait ölçümlerde fay izi tespit edilmiştir. Çöğürlü fayı üzerinde yapılan araştırmalar fayın Akdeniz kıyısına kadar uzandığı olasılıkla Kıbrıs Yayı ile bağlantılı olduğunu göstermektedir. Jeolojik ve jeofizik veriler Hatay Grabeni'nin DAFZ, ÖDFZ ve Kıbrıs Yayı etkisinde gelişen bir üçlü eklem olduğunu ortaya koymaktadır.In this study, geological and geophysical methods were used to determine the faults and their geometries in Antakya and its surroundings and to investigate their effects on morphology. In this context primarily by using the morphological analysis of satellite imagery and digital field data, measurements were made after the field work is completed by observing and mapping tectonic structures. The determined faults were evaluated mainly by using geological and geomorphological methods and additionally by using geophysical methods, then their activities were interpreted. In the study, the Plio-Quaternary sediments, fault systems, surface ruptures form by earthquakes and morphotectonic elements mapped in detail. In addition, the active faults in and around Antakya were examined and investigated by using Ground Penetrating Radar (GPR) method. Geological evaluations have shown that there are two dominant systems in the graben; lateral strike-slip and vertical slip. Vertical strike-slip faults are described as forming the graben, whereas lateral strike-slip faults that cut Pliocene and Miocene units interpreted as active faults. But these faultings could not be aged. Ground Penetrating Radar measurements were taken with a total of 66 profiles. The extension of Sutaşı and Çöğürlü faults which are thought to be active were investigated. As a result of the investigations, fault is detected on southern west part of Sutaşı Fault. On the other hand the studies have shown that Çöğürlü fault is likely to extend to the Mediterranean and it can be linked with the Cyprus Arc. In conclusion geophysical and geological data exhibits that Hatay Graben is a developing triple junction under the influence of DSFZ-EAFZ-Cyprus Arc.Yüksek LisansM.Sc

Palaeaomagnetic Research On The Palaeozoic Of Istanbul And The Place Of The Latter İn Hercynides

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2018Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2018Rodop-Pontid kıtasının bir parçası olan İstanbul tektonik birliği Neoproterozoyik metamorfik bir temel üzerine yerleşmiş Paleozoyik bir istif ile tanımlanır. İstanbul sınırları içerisinde bu istif Ordovisyen'den erken Karbonifer'e sürekli bir gelişim gösterir. Üst Karbonifer molasına geçen Alt Karbonifer fliş çökelleri ve hemen ardından gelen uyumsuzluk ile Avrupa Hersinidleri'ne benzerlik gösterir. İstanbul Paleozoyik parçası (İstanbul+Çamdağ+Zonguldak) hakkında genel bir tektonik yorum yapılamayacak kadar küçük bir alanı işgal etmektedir. Bu nedenle öncelikle ait olduğu düşünülen Hersiniyen Orojen'i ele alınmıştır. Avrupa Hersinidlerinden elde edilen 1138 adet yüksek kaliteli izotopik yaş verisi Ediyakaran'dan başlayıp geç Karbonifer'e kadar faaliyet göstermiş olan ve Gondwana-Land'ın kuzey kıta kenarını oluşturan bir magmatik yayın ürünleri olarak yorumlanmıştır. Elde edilen veriler bu magmatik yayın Hersiniyen Sistemi'nin bel kemiğini oluşturduğunu göstermektedir. Bu çalışmada bu yaya "Protogonos" (= ilk oluşan) adı verilmiştir. Yaş verilerine ek olarak manyetik anomali haritaları ve kılavuz hatlar kullanılarak bu yayın uzanımı ve gelişimi takip edilmiştir. Bu tez kapsamında yapılan paleomanyetik gözlemler, İstanbul Paleozoyik parçasınının Hersiniyen Orojeni'nin içerisindeki konumu belirlemek amacıyla yapılmıştı. Ancak İstanbul'u oluşturan tüm Paleozoyik kayaçların ikincil mıknatıslanmaya maruz kalmış olmaları Paleozoyik'teki mıknatıslanmalarını kaybetmelerine sebep olmuştur. Yapılan gözlemler yeniden mıknatıslanmanın genellikle Kenozoyik dönemin son evresinde olduğunu göstermiştir. Bu nedenle İstanbul tektonik birliğine ait paleoenlem ya da dönme bilgisi elde etmek mümkün olmamıştır. Bu sonuç, bu tezin önemli sonuçlarından biri olup bundan sonra İstanbul'da paleomanyetik gözlemlerle vakit kaybedilmemesini sağlayacaktır. İstanbul Paleozoyik parçasının Gondwana-Land kökenli olduğu gösterilmiş olan Moezya ve Tepla-Barrandiyum birliği ile birlikte Protogonos yayının ardında, Orta Karbonifer'e kadar Gondwana-Land'a ait olduğu düşünülmektedir. Moezya'nın batısından itibaren meydana gelen Gondwana-Land/Lavrusya çarpışması Avrupa ve Kuzey Amerika'da Hersinid orogenik kuşağını oluşturmuş, Moezya'nın batısında kalan kesim ise Gondwana-Land'ın Paleo-Tetis kenarını oluşturarak tektonik evrimine Kimmeridler olarak devam etmiştir. Bu evrim de Jura'da Kimmerid çarpışması ile son bulmuştur. Bu şekilde Karadeniz çevresinde herhangi bir Hersinyen (veya bir diğer adıyla Varisk) olaylarının olmadığı tespit edilmiştir. Burada sunulan Hersinid modeli tamamen orjinal bir model olup bugüne kadar dünyada ileri sürülen Hersinid evrim modellerinden tamamen farklıdır. Bu modelin eldeki stratigrafik, paleontolojik ve yapısal verilerle diğer modellerden daha uyumlu olduğu görülmüştür.The Istanbul tectonic unit is a part of a bigger continental fragment called the Rhodope-Pontide Fragment, and it consists, at the base, of a Neoproterozoic crystalline basement. This basement is overlain by a continuous, well-developed sedimentary sequence extending from the Lower Ordovician to the Upper Carboniferous. The Palaeozoic sequence commences with laminated siltstones and shales. The following thick arkoses are covered by Upper Ordovician-Lower Silurian feldspathic quartz arenite representing a low energy open shelf, probably tidal and beach environment. The basin became progressively deeper and more stable during the Silurian and Devonian. Lower-Middle Devonian nodular limestones show a transition from open shelf to a slope setting. Continuous deepening Lower Carboniferous black lydites. The basin, which was tectonically stable from the Ordovician to the end of the Devonian, became a site of turbiditic flysch deposition and tectonically active during the Early Carboniferous. The Carboniferous flysch marks the progress of a collision. That collision created a dominantly (now) west vergent marginal fold and thrust belt on the eastern side of the Bosphorus and what now seems an east vergent (but with many inconsistencies) on the western side as a retrocharriage. The structural style of folds and faults requires a décollement underneath the whole city which thrusts the entire structure westward. The İstanbul Zone has a complicated deformation history related to the Hercynide (or Scythide), Cimmeride and Alpide orogenies. Although the region of Istanbul shows a weak metamorphism and a weak cleavage development, constraining the entire history of the deformation in the İstanbul Zone marginal fold and thrust belt is a difficult task, primarily due to the multiple deformation phases. But yet it is not impossible. The Palaeozoic sequence is cut by late Cretaceous plutonics together with dacitic and andesitic dykes. This arc magmatism is ascribed to the north-dipping subduction of the Neo-Tethyan ocean along the İzmir-Ankara-Erzincan suture. The Palaeozoic sequence is unconformably overlain by Permian and younger sedimentary strata. Istanbul tectonic unit resembles the Hercynides with its abundant Lower Carboniferous flysch deposits passing into Upper Carboniferous molasse and with a sharp unconformity upon its sediments. The Palaeozoic sequences of Istanbul and Zonguldak have been compared and correlated with similar sequences in Europe, including the Moesian platform in Romania and Bulgaria, Moravo-Silesia (Brunovistulian) in the Czech Republic and the Rhenohercynian zone in Germany and Belgium, all deposited on the northern passive margin of the Rheic ocean. The Istanbul Zone is treated as a part of Avalonia. However, continuous transgressive sedimentation and absence of collision related magmatics or volcaniclastic sediments rule out this relationship. By contrast, the Istanbul sequence resembles the Pyrenees, the Carnic Alps, the Bohemian (Saxo-Thuringian) sequences and thus northern Gondwana-Land of the Palaeozoic times. The zircon ages from its Neoproterozoic basement suggest that İstanbul Zone once was located at the north-eastern margin of Gondwana-Land, recent paleontological studies place the İstanbul Zone to about 30–400S for early Ordovician. Devonian fauna shows similarities with Thuringia, Rhenish Massif, Cantabrian Mountains, Pyrenees, Holy Cross Mts. and North Africa. In this study a total of 688 samples were obtained from 54 sites around İstanbul and Kocaeli. 465 samples collected from the Palaeozoic sedimentary rocks and 223 samples belong to the dykes that cut these sediments and lavas, and related ashes, tuffs that overlay these sediments. 624 standard palaeomagnetic specimens were prepared from 688 samples, and 547 of them are successfully completed their demagnetization steps. The specimens were demagnetized in the laboratory by using both AF and thermal treatments depending on their effectiveness. After demagnetization treatments, 290 specimens showed stable demagnetization patterns and majority of these samples have a characteristic remanant magnetization component close to the present day geomagnetic field. Palaeomagnetic data processing were made on RemaSoft 3.0 and IAPD2014 softwares. Demagnetization studies demonstrate variable degrees of overprinting in a large number of samples. After the application of the tilt correction, %70 of the specimens failed the fold test at site level (early Ordovician siltstones; late Silurian-early Devonian limestones; late Devonian limestones; early Carboniferous turbidites). Rest of them clearly got scattered with increasing α95 and decreasing k values (mid Ordovician conglomerates; mid-late Devonian shales; late Ordovician-early Silurian sandstone and siltstones). This secondary magnetization, acquired during or after the folding event, constitutes evidence of pervasive remagnetization that can be caused viscous remanant magnetization. The İstanbul tectonic unit (İstanbul-Çamdağ-Zonguldak) occupies a rather small area that makes its tectonic evolution hard to reconstruct. This raises the necessity of dealing with the European Hercynides. The Hercynides of Europe are part of a large (~1000 km broad and ~8000 km long) Palaeozoic mountain belt, which was formed as a result of diachronic collision between Laurussia±Baltica and Gondwana-Land at the end of the Carboniferous. This system extends from the Caucasus to the Appalachians. In this thesis we mainly focused on European side of this orogenic belt and used methodology of comparative anatomy of orogens. Every orogenic belt has its own organs represented by distinctive rocks. Fore-arc, arc, back-arc basin, a continental shelf (clastic shelf, shallow shelf, and/or carbonate platform) are basic organs of an orogenic belt. These organs may not be present in every orogenic belt but the most common feature among all these organs is the magmatic arc. Magmatic rock types are strongly related to geodynamic environments. Well-typed and well-dated magmatic rocks can be used as indicators of geodynamic environments, and even further as tracers of geodynamic evolution. To identify the magmatic arcs, the intermediate and felsic magmatic rocks, namely granodiorites, diorites, andesites, granites, and rhyolites are used. For this purpose geological maps of the Germany, Spain, England, France, Czech Republic, Austria, Poland were digitized and mapped as one geological map. ~2700 high quality isotopic age data are collected from the literature. 1138 of them are interpreted as products of a single magmatic arc which had been active from the Ediacaran to the late Carboniferous on the northern margin of Gondwana-Land. The magmatic anomaly maps also used to track this magmatic fragments. This magmatic arc is herein named "Protogonos" (=the first born) in this study. Magnetic anomaly maps and structural trend lines are used as supplements in identifying the extent and evolution of Protogonos. Palaeomagnetic studies revealed remagnetization in the Palaeozoic rocks of İstanbul. The timing of this event coincides with the latest Cainozoic. As a result of this remagnetization we are unable to find a paleolatitude or a rotation for the Palaeozoic rocks. The final step of this thesis is reconstructing the tectonic units and find a proper place for İstanbul tectonic unit. The magmatic arc is the key point in this reconstruction. The fragments of this magmatic arc repositioned according to the displacements on the major transform faults at that time. For this purpose, we used Pangaea B reconstruction template to replace the tectonic units. We propose a retro-arc setting for the İstanbul tectonic unit with Moesia and Tepla-Barrandium behind the Protogonos magmatic arc as part of Gondwana-Land until the medial Carboniferous. While the western part of Hercynian orogen went through collision and formed an orogenic belt from North America and North-western Africa to Moesia, the eastern part including the İstanbul tectonic unit remained untouched by this collision and continued its tectonic evolution as a part of Palaeo-Tethys margin. This episode is ended in Jurassic with the Cimmeride collision. This leads us to the conclusion that no Hercynian event is present in the İstanbul tectonic unit.DoktoraPh

The Strandja Massif and the İstanbul Zone were once parts of the same palaeotectonic unit: new data from Triassic detrital zircons

Spatially continuous rock assemblages that share similar environmental evolution or structural features can be classified as a single tectonic unit. This approach enables to link dispersed units or massifs with each other and sometimes can be subjective, depending on the classification criteria. The relationship and the nature of the contact between the Strandja Massif and the İstanbul Zone have been controversial due to the Cainozoic cover. Amalgamation of these units was claimed as early as the Aptian-Albian. Lower Triassic sedimentary rocks, which are overlain by the Carboniferous flysch with a N-verging thrust fault are exposed NW of the İstanbul Zone. This study reveals the spatial relationship between the Strandja Massif and the İstanbul Zone deduced from the U-Pb dating and Lu-Hf isotopes of the detrital zircons from these Lower Triassic clastics. Our results show that the early Triassic basin was fed from a provenance that included arc-related Upper Carboniferous-Lower Permian magmatic rocks which is much more likely to be the Strandja Massif than the İstanbul Zone. The second outcome of this study is that a unit that previously assigned to Palaeozoic turned out to be Triassic, which brings the Strandja Massif farther to the east, into the northern İstanbul Zone

The Strandja Massif and the İstanbul Zone were once parts of the same palaeotectonic unit: new data from Triassic detrital zircons

<p>Spatially continuous rock assemblages that share similar environmental evolution or structural features can be classified as a single tectonic unit. This approach enables to link dispersed units or massifs with each other and sometimes can be subjective, depending on the classification criteria. The relationship and the nature of the contact between the Strandja Massif and the İstanbul Zone have been controversial due to the Cainozoic cover. Amalgamation of these units was claimed as early as the Aptian-Albian.</p> <p>Lower Triassic sedimentary rocks, which are overlain by the Carboniferous flysch with a N-verging thrust fault are exposed NW of the İstanbul Zone. This study reveals the spatial relationship between the Strandja Massif and the İstanbul Zone deduced from the U-Pb dating and Lu-Hf isotopes of the detrital zircons from these Lower Triassic clastics. Our results show that the early Triassic basin was fed from a provenance that included arc-related Upper Carboniferous-Lower Permian magmatic rocks which is much more likely to be the Strandja Massif than the İstanbul Zone. The second outcome of this study is that a unit that previously assigned to Palaeozoic turned out to be Triassic, which brings the Strandja Massif farther to the east, into the northern İstanbul Zone.</p

The geology and morphology of the Antakya Graben between the Amik Triple Junction and the Cyprus Arc

In southeastern Turkey, the NE-trending Antakya Graben forms an asymmetric depression filled by Pliocene marine siliciclastic sediment, Pleistocene to Recent fluvial terrace sediment, and alluvium. Along the Mediterranean coast of the graben, marine terrace deposits sit at different elevations ranging from 2 to 180 m above present sea level, with ages ranging from MIS 2 to 11. A multisegmented, dominantly sinistral fault lying along the graben may connect the Cyprus Arc in the west to the Amik Triple Junction on the Dead Sea Fault (DSF) in the east. Normal faults, which are younger than the sinistral ones, bound the graben's southeastern margin. The westward escape of the continental Iskenderun Block, delimited by sinistral fault segments belonging to the DSF in the east and the Eastern Anatolian Fault in the north caused the development of a sinistral transtensional tectonic regime, which has opened the Antakya Graben since the Pliocene. In the later stages of this opening, normal faults developed along the southeastern margin that caused the graben to tilt to the southwest, leading to differential uplift of Mediterranean coastal terraces. Most of these normal faults remain active. In addition to these tectonic movements, Pleistocene sea level changes in the Mediterranean affected the geomorphological evolution of the area

Subduction and Slab Detachment Under Moving Trenches During Ongoing India-Asia Convergence

The dynamics of slab detachment and associated geological fingerprints have been inferred from various numerical and analog models. These invariably use a setup with slab-pull-driven convergence in which a slab detaches below a mantle-stationary trench after the arrest of plate convergence due to arrival of continental lithosphere. In contrast, geological reconstructions show that post-detachment plate convergence is common and that trenches and sutures are rarely mantle-stationary during detachment. Here, we identify the more realistic kinematic context of slab detachment using the example of the India-Asia convergent system. We first show that only the India and Himalayas slabs (from India's northern margin) and the Carlsberg slab (from the western margin) unequivocally detached from Indian lithosphere. Several other slabs below the Indian Ocean do not require a Neotethyan origin and may be of Mesotethys and Paleotethys origin. Additionally, the still-connected slabs are being dragged together with the Indian plate forward (Hindu Kush) or sideways (Burma, Chaman) through the mantle. We show that Indian slab detachment occurred at moving trenches during ongoing plate convergence, providing more realistic geodynamic conditions for use in future numerical and analog experiments. We identify that the actively detaching Hindu Kush slab is a type-example of this setting, whilst a 25–13 Ma phase of shallow detachment of the Himalayas slab, here reconstructed from plate kinematics and tomography, agrees well with independent, published geological estimates from the Himalayas orogen of slab detachment. The Sulaiman Ranges of Pakistan may hold the geological signatures of detachment of the laterally dragged Carlsberg slab