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1

Dominique, Cluzel, Iseppi Marion y Chen Yan. "Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence". Tectonophysics 811 (julio de 2021): 228875. http://dx.doi.org/10.1016/j.tecto.2021.228875.

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2

Muhtar, M. N., Chang-Zhi Wu, M. Santosh, Ru-Xiong Lei, Lian-Xing Gu, Si-Meng Wang y Kai Gan. "Late Paleozoic tectonic transition from subduction to post-collisional extension in Eastern Tianshan, Central Asian Orogenic Belt". GSA Bulletin 132, n.º 7-8 (23 de diciembre de 2019): 1756–74. http://dx.doi.org/10.1130/b35432.1.

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Abstract Late Paleozoic large-scale transcurrent tectonics and synkinematic intrusions are prominent features in the Eastern Tianshan segment of the southwestern Central Asian Orogenic Belt. However, the spatial and temporal relationship between synkinematic intrusions and crustal-scale shear zones remains unclear. Here we report petrology, geochemistry, and geochronology of the Qiziltag pluton associated with the Kanggur-Huangshan Shear Zone (KHSZ) with a view to characterize the spatial and temporal relationship between synkinematic intrusions and large-scale transcurrent shearing. Field relations and zircon U-Pb ages indicate that the Qiziltag pluton was formed through two stages of magmatism, with earlier stage granitoids (gneissic biotite granite: 288.9 ± 1.9 Ma, biotite monzogranite: 291.5 ± 1.7 Ma, K-feldspar granite: 287.9 ± 3.1 Ma), and later stage bimodal intrusions (biotite quartz monzonite: 278.5 ± 1.8 Ma, gabbro: 278.1 ± 2.3 Ma). The earlier stage granitoids are high-K calc-alkaline, enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs; e.g., Rb, Th, and U), and depleted in high field strength elements (HFSEs; e.g., Nb, Ta, and Ti). Combined with their depleted isotopic compositions (εNd(t) = +6.29 to +7.48) and juvenile model ages (TDM2 = 450–610 Ma), we infer that the granitoids were derived from juvenile lower crust in a post-collisional tectonic transition (from compression to extension). The structural and temporal features indicate that the earlier stage (ca. 290 Ma) granitoids formed prior to the regional large-scale dextral strike slip. The later stage bimodal intrusions are dominated by biotite quartz monzonite as the felsic member and gabbro as the mafic component. The biotite quartz monzonite is high-K calc-alkaline with enriched LREEs and LILEs (e.g., Rb, Th, and U), and depleted HFSEs (e.g., Nb, Ta, and Ti), whereas the gabbro is subalkalic with depleted LREEs and HFSEs (e.g., Nb and Ta), resembling normal mid-ocean ridge basalt features. The bimodal intrusions show similar isotopic compositions (εNd(t) = +6.41 to +6.72 and εHf(t) = +9.55 to + 13.85 for biotite quartz monzonite; εNd(t) = +9.13 to +9.69 and εHf(t) = +4.80 to +14.07 for gabbro). These features suggest that the later stage (ca. 280 Ma) bimodal intrusions were derived from partial melting of depleted mantle and anatectic melting of lower crust materials induced by synchronous underplating of basaltic magma in a post-collisional extension. The structural features of the bimodal intrusions indicate that the later stage (ca. 280 Ma) magmatism was coeval with the development of the KHSZ. In conjunction with spatial and temporal evolution of magmatism and sedimentary records of Eastern Tianshan, we infer that transition between the northward closure of the North Tianshan Ocean and subsequent collision between the Central Tianshan Massif and the Qoltag Arc belt occurred at ca. 300 Ma.
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3

Verstappen, Herman Th. "Indonesian Landforms and Plate Tectonics". Indonesian Journal on Geoscience 5, n.º 3 (28 de septiembre de 2010): 197–207. http://dx.doi.org/10.17014/ijog.5.3.197-207.

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DOI: 10.17014/ijog.v5i3.103The horizontal configuration and vertical dimension of the landforms occurring in the tectonically unstable parts of Indonesia were resulted in the first place from plate tectonics. Most of them date from the Quaternary and endogenous forces are ongoing. Three major plates – the northward moving Indo-Australian Plate, the south-eastward moving SE-Asian Plate and the westward moving Pacific Plate - meet at a plate triple-junction situated in the south of New Guinea’s Bird’s Head. The narrow North-Moluccan plate is interposed between the Asia and Pacific. It tapers out northward in the Philippine Mobile Belt and is gradually disappearing. The greatest relief amplitudes occur near the plate boundaries: deep ocean trenches are associated with subduction zones and mountain ranges with collision belts. The landforms of the more stable areas of the plates date back to a more remote past and, where emerged, have a more subdued relief that is in the first place related to the resistance of the rocks to humid tropical weathering Rising mountain ranges and emerging island arcs are subjected to rapid humid-tropical river erosions and mass movements. The erosion products accumulate in adjacent sedimentary basins where their increasing weight causes subsidence by gravity and isostatic compensations. Living and raised coral reefs, volcanoes, and fault scarps are important geomorphic indicators of active plate tectonics. Compartmental faults may strongly affect island arcs stretching perpendicular to the plate movement. This is the case on Java. Transcurrent faults and related pull-apart basins are a leading factor where plates meet at an angle, such as on Sumatra. The most complicated situation exists near the triple-junction and in the Moluccas. Modern research methods, such as GPS measurements of plate movements and absolute dating of volcanic outbursts and raised coral reefs are important tools. The mega-landforms resulting from the collision of India with the Asian continent, around 50.0 my. ago, and the final collision of Australia with the Pacific, about 5.0 my. ago, also had an important impact on geomorphologic processes and the natural environment of SE-Asia through changes of the monsoonal wind system in the region and of the oceanic thermo-haline circulation in eastern Indonesia between the Pacific and the Indian ocean. In addition the landforms of the region were, of course, affected by the Quaternary global climatic fluctuations and sea level changes.
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4

Bussy, François, Jean Hernandez y Jürgen Von Raumer. "Bimodal magmatism as a consequence of the post-collisional readjustment of the thickened Variscan continental lithosphere (Aiguilles Rouges-Mont Blanc Massifs, Western Alps)". Earth and Environmental Science Transactions of the Royal Society of Edinburgh 91, n.º 1-2 (2000): 221–33. http://dx.doi.org/10.1017/s0263593300007392.

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High Precision U-Pb zircon and monazite dating in the Aiguilles Rouges–Mont Blanc area allowed discrimination of three short-lived bimodal magmatic pulses: the early 332 Ma Mg–K Pormenaz monzonite and associated 331 Ma peraluminous Montées Pélissier monzogranite; the 307 Ma cordierite-bearing peraluminous Vallorcine and Fully intrusions; and the 303 Fe-K Mont Blanc syenogranite. All intruded syntectonically along major-scale transcurrent faults at a time when the substratum was experiencing tectonic exhumation, active erosion recorded in detrital basins and isothermal decompression melting dated at 327-320 Ma. Mantle activity and magma mixing are evidenced in all plutons by coeval mafic enclaves, stocks and synplutonic dykes. Both crustal and mantle sources evolve through time, pointing to an increasingly warm continental crust and juvenile asthenospheric mantle sources. This overall tectono-magmatic evolution is interpreted in a scenario of post-collisional restoration to normal size of a thickened continental lithosphere. The latter re-equilibrates through delamination and/or erosion of its mantle root and tectonic exhumation/erosion in an overall extensional regime. Extension is related to either gravitational collapse or back-arc extension of a distant subduction zone.
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5

Hinschberger, Florent, Jacques André Malod, Jean Pierre Réhault y Safri Burhanuddin. "Contribution of bathymetry and geomorphology to the geodynamics of the East Indonesian Seas". Bulletin de la Société Géologique de France 174, n.º 6 (1 de noviembre de 2003): 545–60. http://dx.doi.org/10.2113/174.6.545.

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Abstract Southeastern Indonesia is located at a convergent triple junction of 3 plates : the Pacific (including the Caro-line and Philippines plates), the Australian and the Southeast Asian plates (fig. 1). The age of the different basins : the North Banda Sea (Sula Basin), the South Banda Sea (Wetar and Damar Basins) and the Weber Trough has been debated for a long time. Their great depth was a reason to interpret them as remnants of oceanic domains either of Indian or Pacific ocean affinities. It has now been demonstrated from geochronological studies that these basins have formed during the Neogene [Réhault et al., 1994 ; Honthaas et al., 1998]. The crust has been sampled only in the Sula Basin, where basalts or trachyandesites with back-arc geochemical signatures have been dredged. Their ages range from 11.4 ± 1.15 to 7.33 ± 0.18 Ma [Réhault et al., 1994 ; Honthaas et al., 1998]. The study of the magnetic anomaly pattern of these basins confirms this interpretation and defines an age between 12.5 and 7.15 Ma for the North Banda Basin and between 6.5 to 3.5 Ma for the South Banda Basin [Hinschberger et al., 2000 ; Hinschberger et al., 2001]. Furthermore, the existence of volcanic arcs linked to subducted slabs suggests that these basins resulted from back-arc spreading and subduction slab roll-back. Lastly, the Weber Trough which exceeds 7 300 m in depth and is one of the deepest non subduction basins in the world, remains enigmatic. A compilation of existing bathymetric data allows us to present a new bathymetric map of the region (fig. 2 and 3). A comparison with the previous published maps [Mammerickx et al., 1976 ; Bowin et al., 1982] shows numerous differences at a local scale. This is especially true for the Banda Ridges or in the Sula Basin where new tectonic directions are expressed. In the North Banda Basin, the Tampomas Ridge, which was striking NE-SW in the previous maps, is actually NW-SE parallel to the West Buru Fracture Zone and to the Hamilton Fault scarp (fig. 6). This NW-SE direction represents the initial direction of rifting and oceanic spreading. In this basin, only the southeastern rifted margin morphology is preserved along the Sinta Ridges. The basin is presently involved in an overall compressional motion and its buckled and fractured crust is subducted westwards beneath East Sulawesi (fig. 4a, 5 and 6). The northern border of the North Banda Basin is reactivated into sinistral transcurrent motion in the South Sula Fracture Zone continued into the Matano fault in Sulawesi. The South Banda Sea Basin is divided in two parts, the Wetar and Damar Basins with an eastward increase in depth. The Wetar and Damar Basins are separated by the NNW-SSE Gunung Api Ridge, characterized by volcanoes, a deep pull apart basin and active tectonics on its eastern flank (fig. 4b and 7). This ridge is interpreted as a large sinistral strike-slip fracture zone which continues across the Banda Ridges and bends towards NW south of Sinta Ridge. The Banda Ridges region, separating the North Banda Basin from the southern Banda Sea (fig. 5 and 7), is another place where many new morphological features are now documented. The Sinta Ridge to the north is separated from Buru island by the South Buru Basin which may constitute together with the West Buru Fracture Zone a large transcurrent lineament striking NW-SE. The central Rama Ridge is made of 2 narrow ridges striking NE-SW with an « en-echelon » pattern indicating sinistral strike slip comparable to the ENE-WSW strike-slip faulting evidenced by focal mechanisms in the northern border of the Damar Basin [Hinschberger, 2000]. Dredging of Triassic platform rocks and metamorphic basement on the Sinta and Rama Ridges suggests that they are fragments of a continental block [Silver et al., 1985 ; Villeneuve et al., 1994 ; Cornée et al., 1998]. The Banda Ridges are fringed to the south by a volcanic arc well expressed in the morphology : the Nieuwerkerk-Emperor of China and the Lucipara volcanic chains whose andesites and arc basalts have been dated between 8 and 3.45 Ma [Honthaas et al., 1998]. Eastern Indonesia deep oceanic basins are linked to the existence of 2 different subduction zones expressed by 2 different downgoing slabs and 2 volcanic arcs : the Banda arc and the Seram arc [Cardwell et Isacks, 1978 ; Milsom, 2001]. They correspond respectively to the termination of the Australian subduction and to the Bird’s head (Irian Jaya) subduction under Seram (fig. 5). Our bathymetric study helps to define the Seram volcanic arc which follows a trend parallel to the Seram Trench from Ambelau island southeast of Buru to the Banda Island (fig. 2 and 5). A new volcanic seamount discovered in the southeast of Buru (location of dredge 401 in figure 7) and a large volcano in the Pisang Ridge (location of dredge 403 in figure 7 and figure 8) have been surveyed with swath bathymetry. Both show a sub-aerial volcanic morphology and a further subsidence evidenced by the dredging of reefal limestones sampled at about 3000 m depth on their flank. We compare the mean basement depths corrected for sediment loading for the different basins (fig. 9). These depths are about 5 000 m in the Sula Basin, 4 800 m in the Wetar basin and 5 100 m in the Damar basin. These values plot about 1 000 m below the age-depth curve for the back-arc basins [Park et al., 1990] and about 2000 m below the Parsons and Sclater’s curve for the oceanic crust [Parsons et Sclater, 1977]. More generally, eastern Indonesia is characterized by large vertical motions. Strong subsidence is observed in the deep basins and in the Banda Ridges. On the contrary, large uplifts characterize the islands with rates ranging between 20 to 250 cm/kyr [De Smet et al., 1989a]. Excess subsidence in the back-arc basins has been attributed to large lateral heat loss due to their small size [Boerner et Sclater, 1989] or to the presence of cold subducting slabs. In eastern Indonesia, these mechanisms can explain only a part of the observed subsidence. It is likely that we have to take into account the tectonic forces linked to plate convergence. This is supported by the fact that uplift motions are clearly located in the area of active collision. In conclusion, the bathymetry and morphology of eastern Indonesian basins reveal a tectonically very active region where basins opened successively in back-arc, intra-arc and fore-arc situation in a continuous convergent geodynamic setting.
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6

Vanderhaeghe, Olivier, Oscar Laurent, Véronique Gardien, Jean-François Moyen, Aude Gébelin, Cyril Chelle-Michou, Simon Couzinié, Arnaud Villaros y Mathieu Bellanger. "Flow of partially molten crust controlling construction, growth and collapse of the Variscan orogenic belt: the geologic record of the French Massif Central". BSGF - Earth Sciences Bulletin 191 (2020): 25. http://dx.doi.org/10.1051/bsgf/2020013.

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We present here a tectonic-geodynamic model for the generation and flow of partially molten rocks and for magmatism during the Variscan orogenic evolution from the Silurian to the late Carboniferous based on a synthesis of geological data from the French Massif Central. Eclogite facies metamorphism of mafic and ultramafic rocks records the subduction of the Gondwana hyperextended margin. Part of these eclogites are forming boudins-enclaves in felsic HP granulite facies migmatites partly retrogressed into amphibolite facies attesting for continental subduction followed by thermal relaxation and decompression. We propose that HP partial melting has triggered mechanical decoupling of the partially molten continental rocks from the subducting slab. This would have allowed buoyancy-driven exhumation and entrainment of pieces of oceanic lithosphere and subcontinental mantle. Geochronological data of the eclogite-bearing HP migmatites points to diachronous emplacement of distinct nappes from middle to late Devonian. These nappes were thrusted onto metapelites and orthogneisses affected by MP/MT greenschist to amphibolite facies metamorphism reaching partial melting attributed to the late Devonian to early Carboniferous thickening of the crust. The emplacement of laccoliths rooted into strike-slip transcurrent shear zones capped by low-angle detachments from c. 345 to c. 310 Ma is concomitant with the southward propagation of the Variscan deformation front marked by deposition of clastic sediments in foreland basins. We attribute these features to horizontal growth of the Variscan belt and formation of an orogenic plateau by gravity-driven lateral flow of the partially molten orogenic root. The diversity of the magmatic rocks points to various crustal sources with modest, but systematic mantle-derived input. In the eastern French Massif Central, the southward decrease in age of the mantle- and crustal-derived plutonic rocks from c. 345 Ma to c. 310 Ma suggests southward retreat of a northward subducting slab toward the Paleotethys free boundary. Late Carboniferous destruction of the Variscan belt is dominantly achieved by gravitational collapse accommodated by the activation of low-angle detachments and the exhumation-crystallization of the partially molten orogenic root forming crustal-scale LP migmatite domes from c. 305 Ma to c. 295 Ma, coeval with orogen-parallel flow in the external zone. Laccoliths emplaced along low-angle detachments and intrusive dykes with sharp contacts correspond to the segregation of the last melt fraction leaving behind a thick accumulation of refractory LP felsic and mafic granulites in the lower crust. This model points to the primordial role of partial melting and magmatism in the tectonic-geodynamic evolution of the Variscan orogenic belt. In particular, partial melting and magma transfer (i) triggers mechanical decoupling of subducted units from the downgoing slab and their syn-orogenic exhumation; (ii) the development of an orogenic plateau by lateral flow of the low-viscosity partially molten crust; and, (iii) the formation of metamorphic core complexes and domes that accommodate post-orogenic exhumation during gravitational collapse. All these processes contribute to differentiation and stabilisation of the orogenic crust.
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7

Percival, John A. "A regional perspective of the Quetico metasedimentary belt, Superior Province, Canada". Canadian Journal of Earth Sciences 26, n.º 4 (1 de abril de 1989): 677–93. http://dx.doi.org/10.1139/e89-058.

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Alternating greenstone–granite and metasedimentary gneiss belts are a first-order tectonic feature of the southern Superior Province. The tectonic development of the Quetico metasedimentary belt is reviewed with regard to depositional, structural, and metamorphic–plutonic history. Over its 1200 km length, the belt consists of marginal metasedimentary schists of turbiditic origin and interior metasedimentary migmatite and peraluminous leucogranite. Polyphase deformation has resulted in a steep easterly-striking foliation and regional, gently east-plunging stretching lineation. Metamorphic grade varies in a low-P facies series from greenschist at the belt margins to upper amphibolite and local granulite in the central migmatite – intrusive granite zone. Mineral assemblages in the central zone yield estimates of metamorphic pressure that increase systematically eastward over 800 km from about 250 MPa (2.5 kbar) near the Canada – United States border to 600 MPa (6 kbar) in granulites adjacent to the Kapuskasing structural zone.Geochronology suggests that sediments were deposited at approximately the same time as active volcanism in adjacent volcanic belts, although evidence of volcanic–sedimentary stratigraphic contiguity is weak as a result of later transcurrent movement parallel to major lithological boundaries. Adjacent belts are inferred to have been contiguous since common D2 deformation, 2689–2684 Ma ago. Major plutonism and associated metamorphism occurred in the Quetico Belt approximately 2670–2650 Ma ago, significantly later than major plutonism in the adjacent volcanic belts.The linear disposition of greywacke-rich sediments over 1200 km invites an analogy with modern accretionary prisms. However, the high-temperature, low-pressure metamorphism of the Quetico Belt is inconsistent with such a low-heat-flow environment, and a change in tectonic regime would be required to account for the metamorphism and intracrustal plutonism. Simple cessation of subduction beneath the thick sedimentary prism could have led to restoration of isotherms, with possible attendant crustal melting and isostatic recovery.
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8

Mackie, D. J., R. M. Clowes, S. A. Dehler, R. M. Ellis y P. Morel-À-l'Huissier. "The Queen Charlotte Islands refraction project. Part II. Structural model for transition from Pacific plate to North American plate". Canadian Journal of Earth Sciences 26, n.º 9 (1 de septiembre de 1989): 1713–25. http://dx.doi.org/10.1139/e89-146.

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The oceanic-continental boundary west of the Queen Charlotte Islands is marked by the active Queen Charlotte Fault Zone. Motion along the fault is predominantly dextral strike slip, but relative plate motion and other studies indicate that a component of convergence between the oceanic Pacific plate and the continental North American plate presently exists. This convergence could be manifest through different types of deformation: oblique subduction, crustal thickening, or lateral distortion of the plates. In 1983, a 330 km offshore–onshore seismic refraction profile extending from the deep ocean across the islands to the mainland of British Columbia was recorded to investigate (i) structure of the fault zone and associated oceanic–continental boundary and (ii) lithospheric structure beneath the islands and Hecate Strait to define the regional transition from Pacific plate to North American plate and thus the nature of the convergence. Two-dimensional ray tracing and synthetic seismogram modelling of many record sections enabled the derivation of a composite velocity structural section along the profile. The structural section also was tested with two-dimensional gravity modelling. Part I of the study addressed the structure of the fault zone; part II addresses lithospheric structure extending eastward to the mainland.The derived velocity structure has some important and well-constrained features: (i) anomalously low crustal velocities (5.3 km/s with a 0.2 km/s per km gradient) underlain by a steep, 19 °eastward-dipping boundary above the mantle in the terrace region west of the main fault; (ii) a thin crust of 21–27 km beneath the Queen Charlotte Islands; and (iii) a gentle 4 °eastward dip of the Moho below Hecate Strait as crustal thickness increases from 27 km to 32 km. The gravity modelling requires that mantle material extend upwards to a depth of about 30 km below the mainland and indicates that an underlying subducted slab, if it exists, extends eastward no farther than the mainland.Unfortunately, the velocity structure delineated by this study could not unambiguously determine the mode of deformation, because the lowermost crustal block beneath Queen Charlotte Islands and Hecate Strait can be interpreted as subducted oceanic crust or middle to lower continental crust. Thus, two different tectonic models for the transition from Pacific plate to North American plate are discussed: in one, oblique subduction is the principal characteristic; in the other, oceanic lithosphere juxtaposed against continental lithosphere across a narrow boundary zone along which only transcurrent motion occurs is the dominant feature. Based on the thin crust beneath the Queen Charlotte Islands, the lack of a wide zone of deformation along the plate boundary region, and other geological and geophysical characteristics, oblique subduction is the more plausible model.
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9

Thurston, Phillips C. "Igneous Rock Associations 19. Greenstone Belts and Granite−Greenstone Terranes: Constraints on the Nature of the Archean World". Geoscience Canada 42, n.º 4 (7 de diciembre de 2015): 437. http://dx.doi.org/10.12789/geocanj.2015.42.081.

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Greenstone belts are long, curvilinear accumulations of mainly volcanic rocks within Archean granite−greenstone terranes, and are subdivided into two geochemical types: komatiite−tholeiite sequences and bimodal sequences. In rare instances where basement is preserved, the basement is unconformably overlain by platform to rift sequences consisting of quartzite, carbonate, komatiite and/or tholeiite. The komatiite−tholeiite sequences consist of km-scale thicknesses of tholeiites, minor intercalated komatiites, and smaller volumes of felsic volcanic rocks. The bimodal sequences consist of basal tholeiitic flows succeeded upward by lesser volumes of felsic volcanic rocks. The two geochemical types are unconformably overlain by successor basin sequences containing alluvial–fluvial clastic metasedimentary rocks and associated calc-alkaline to alkaline volcanic rocks. Stratigraphically controlled geochemical sampling in the bimodal sequences has shown the presence of Fe-enrichment cycles in the tholeiites, as well as monotonous thicknesses of tholeiitic flows having nearly constant MgO, which is explained by fractionation and replenishment of the magma chamber with fresh mantle-derived material. Geochemical studies reveal the presence of boninites associated with the komatiites, in part a result of alteration or contamination of the komatiites. Within the bimodal sequences there are rare occurrences of adakites, Nb-enriched basalts and magnesian andesites. The greenstone belts are engulfed by granitoid batholiths ranging from soda-rich tonalite−trondhjemite−granodiorite to later, more potassic granitoid rocks. Archean greenstone belts exhibit a unique structural style not found in younger orogens, consisting of alternating granitoid-cored domes and volcanic-dominated keels. The synclinal keels are cut by major transcurrent shear zones. Metamorphic patterns indicate that low pressure metamorphism of the greenstones is centred on the granitoid batholiths, suggesting a central role for the granitoid rocks in metamorphosing the greenstones. Metamorphic patterns also show that the proportion of greenstones in granite−greenstone terranes diminishes with deeper levels of exposure. Evidence is presented on both sides of the intense controversy as to whether greenstone belts are the product of modern plate tectonic processes complete with subduction, or else the product of other, lateral tectonic processes driven by the ‘mantle wind.’ Given that numerous indicators of plate tectonic processes – structural style, rock types, and geochemical features − are unique to the Archean, it is concluded that the evidence is marginally in favour of non-actualistic tectonic processes in Archean granite−greenstone terranes.RÉSUMÉLes ceintures de roches vertes sont des accumulations longiformes et curvilinéaires, principalement composées de roches volcaniques au sein de terranes granitique archéennes, et étant subdivisées en deux types géochimiques: des séquences à komatiite–tholéite et des séquences bimodales. En de rares occasions, lorsque le socle est préservé, ce dernier est recouvert en discordance par des séquences de plateforme ou de rift, constituées de quartzite, carbonate, komatiite et/ou de tholéiite. Les séquences de komatiite-tholéiite forment des épaisseurs kilométriques de tholéiite, des horizons mineurs de komatiites, et des volumes de moindre importance de roches volcaniques felsiques. Les séquences bimodales sont constituées à la base, de coulées tholéiitiques surmontées par des volumes mineurs de roches volcaniques felsiques. Ces deux types géochimiques sont recouverts en discordance par des séquences de bassins en succession contenant des roches métasédimentaires clastiques fluvio-alluvionnaires associées à des roches volcaniques calco-alcalines à alcalines. Un échantillonnage à contrôle stratigraphique des séquences bimodales a révélé la présence de cycles d’enrichissement en Fe dans les tholéiites, ainsi que des épaisseurs continues d’épanchements tholéiitiques ayant des valeurs presque constante en MgO, qui s’explique par la cristallisation fractionnée et le réapprovisionnement de la chambre magmatique par du matériel mantélique. Les études géochimiques montrent la présence de boninites associées aux komatiites, résultant en partie de l’altération ou de la contamination des komatiites. Au sein des séquences bimodales, on retrouve en de rares occasions des adakites, des basaltes enrichis en Nb et des andésites magnésiennes. Les ceintures de roches vertes sont englouties dans des batholites granitoïdes de composition passant des tonalites−trondhjémites−granodiorites enrichies en sodium, à des roches granitoïdes tardives plus potassiques. Les ceintures de roches vertes archéennes montrent un style structural unique que l’on ne retrouve pas dans des orogènes plus jeunes, et qui est constitué d’alternances de dômes à cœur granitoïdes et d`affaissements principalement composés de roches volcaniques. Les synclinaux formant les affaissements sont recoupés par de grandes zones de cisaillement. Les profils métamorphiques indiquent que le métamorphisme de basse pression des roches vertes est centré sur les batholites, indiquant un rôle central des roches granitoïdes durant le métamorphisme des roches vertes. Les profils métamorphiques montrent également que la proportion de roches vertes dans les terranes granitiques diminue avec l’exposition des niveaux plus profonds. On présente les arguments des deux côtés de l’intense controverse voulant que les ceintures de roches vertes soient le produit de processus moderne de la tectonique des plaques incluant la subduction, ou alors le produit d’autres processus tectoniques découlant du « flux mantélique ». Étant donné la présence des indicateurs des processus de tectonique des plaques – style structural, les types de roches, et les caractéristiques géochimiques – ne se retrouvent qu’à l’Archéen, nous concluons que les indices favorisent légèrement l’option de processus tectoniques non-actuels dans les terranes granitiques de roches vertes à l’Archéen.
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10

Doblas, Miguel. "Late hercynian extensional and transcurrent tectonics in Central Iberia". Tectonophysics 191, n.º 3-4 (junio de 1991): 325–34. http://dx.doi.org/10.1016/0040-1951(91)90065-z.

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11

Lu, Chia-Yu, Jacques Angelier, Hao-Tsu Chu y Jian-Cheng Lee. "Contractional, transcurrent, rotational and extensional tectonics: examples from Northern Taiwan". Tectonophysics 246, n.º 1-3 (junio de 1995): 129–46. http://dx.doi.org/10.1016/0040-1951(94)00252-5.

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12

Brown, Michael, Tim Johnson y Nicholas J. Gardiner. "Plate Tectonics and the Archean Earth". Annual Review of Earth and Planetary Sciences 48, n.º 1 (30 de mayo de 2020): 291–320. http://dx.doi.org/10.1146/annurev-earth-081619-052705.

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If we accept that a critical condition for plate tectonics is the creation and maintenance of a global network of narrow boundaries separating multiple plates, then to argue for plate tectonics during the Archean requires more than a local record of subduction. A case is made for plate tectonics back to the early Paleoproterozoic, when a cycle of breakup and collision led to formation of the supercontinent Columbia, and bimodal metamorphism is registered globally. Before this, less preserved crust and survivorship bias become greater concerns, and the geological record may yield only a lower limit on the emergence of plate tectonics. Higher mantle temperature in the Archean precluded or limited stable subduction, requiring a transition to plate tectonics from another tectonic mode. This transition is recorded by changes in geochemical proxies and interpreted based on numerical modeling. Improved understanding of the secular evolution of temperature and water in the mantle is a key target for future research. ▪ Higher mantle temperature in the Archean precluded or limited stable subduction, requiring a transition to plate tectonics from another tectonic mode. ▪ Plate tectonics can be demonstrated on Earth since the early Paleoproterozoic (since c. 2.2 Ga), but before the Proterozoic Earth's tectonic mode remains ambiguous. ▪ The Mesoarchean to early Paleoproterozoic (3.2–2.3 Ga) represents a period of transition from an early tectonic mode (stagnant or sluggish lid) to plate tectonics. ▪ The development of a global network of narrow boundaries separating multiple plates could have been kick-started by plume-induced subduction.
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13

Ben-Avraham, Zvi, Gerald Schubert, Emanuele Lodolo y Uri Schattner. "Ripple Tectonics—When Subduction Is Interrupted". Positioning 11, n.º 03 (2020): 33–44. http://dx.doi.org/10.4236/pos.2020.113003.

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14

Ben-Avraham, Zvi, Gerald Schubert, Emanuele Lodolo y Uri Schattner. "Ripple Tectonics—When Subduction Is Interrupted". Positioning 11, n.º 03 (2020): 33–44. http://dx.doi.org/10.4236/pos.2020.113003.

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15

Ben-Avraham, Zvi, Gerald Schubert, Emanuele Lodolo y Uri Schattner. "Ripple Tectonics—When Subduction Is Interrupted". Positioning 11, n.º 03 (2020): 33–44. http://dx.doi.org/10.4236/pos.2020.113303.

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16

O'Neill, Craig, Simon Turner y Tracy Rushmer. "The inception of plate tectonics: a record of failure". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, n.º 2132 (octubre de 2018): 20170414. http://dx.doi.org/10.1098/rsta.2017.0414.

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The development of plate tectonics from a pre-plate tectonics regime requires both the initiation of subduction and the development of nascent subduction zones into long-lived contiguous features. Subduction itself has been shown to be sensitive to system parameters such as thermal state and the specific rheology. While generally it has been shown that cold-interior high-Rayleigh-number convection (such as on the Earth today) favours plates and subduction, due to the ability of the interior stresses to couple with the lid, a given system may or may not have plate tectonics depending on its initial conditions. This has led to the idea that there is a strong history dependence to tectonic evolution—and the details of tectonic transitions, including whether they even occur, may depend on the early history of a planet. However, intrinsic convective stresses are not the only dynamic drivers of early planetary evolution. Early planetary geological evolution is dominated by volcanic processes and impacting. These have rarely been considered in thermal evolution models. Recent models exploring the details of plate tectonic initiation have explored the effect of strong thermal plumes or large impacts on surface tectonism, and found that these ‘primary drivers’ can initiate subduction, and, in some cases, over-ride the initial state of the planet. The corollary of this, of course, is that, in the absence of such ongoing drivers, existing or incipient subduction systems under early Earth conditions might fail. The only detailed planetary record we have of this development comes from Earth, and is restricted by the limited geological record of its earliest history. Many recent estimates have suggested an origin of plate tectonics at approximately 3.0 Ga, inferring a monotonically increasing transition from pre-plates, through subduction initiation, to continuous subduction and a modern plate tectonic regime around that time. However, both numerical modelling and the geological record itself suggest a strong nonlinearity in the dynamics of the transition, and it has been noted that the early history of Archaean greenstone belts and trondhjemite–tonalite–granodiorite record many instances of failed subduction. Here, we explore the history of subduction failure on the early Earth, and couple these with insights from numerical models of the geodynamic regime at the time. This article is part of a discussion meeting issue ‘Earth dynamics and the development of plate tectonics'.
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17

Wan, Bo, Xusong Yang, Xiaobo Tian, Huaiyu Yuan, Uwe Kirscher y Ross N. Mitchell. "Seismological evidence for the earliest global subduction network at 2 Ga ago". Science Advances 6, n.º 32 (agosto de 2020): eabc5491. http://dx.doi.org/10.1126/sciadv.abc5491.

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The earliest evidence for subduction, which could have been localized, does not signify when plate tectonics became a global phenomenon. To test the antiquity of global subduction, we investigated Paleoproterozoic time, for which seismic evidence is available from multiple continents. We used a new high-density seismic array in North China to image the crustal structure that exhibits a dipping Moho bearing close resemblance to that of the modern Himalaya. The relict collisional zone is Paleoproterozoic in age and implies subduction operating at least as early as ~2 billion years (Ga) ago. Seismic evidence of subduction from six continents at this age is interpreted as the oldest evidence of global plate tectonics. The sutures identified can be linked in a plate network that resulted in the assembly of Nuna, likely Earth’s first supercontinent. Global subduction by ~2 Ga ago can explain why secular planetary cooling was not appreciable until Proterozoic time.
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18

Gerya, Taras. "Numerical modeling of subduction: State of the art and future directions". Geosphere 18, n.º 2 (9 de febrero de 2022): 503–61. http://dx.doi.org/10.1130/ges02416.1.

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Abstract During the past five decades, numerical modeling of subduction, one of the most challenging and captivating geodynamic processes, remained in the core of geodynamic research. Remarkable progress has been made in terms of both in-depth understanding of different aspects of subduction dynamics and deciphering the diverse and ever-growing array of subduction zone observations. However, numerous key questions concerning subduction remain unanswered defining the frontier of modern Earth Science research. This review of the past decade comprises numerical modeling studies focused on 12 key open topics: Subduction initiationSubduction terminationSlab deformation, dynamics, and evolution in the mantle4D dynamics of subduction zonesThermal regimes and pressure-temperature (P-T) paths of subducted rocksFluid and melt processes in subduction zonesGeochemical transport, magmatism, and crustal growthTopography and landscape evolutionSubduction-induced seismicityPrecambrian subduction and plate tectonicsExtra-terrestrial subductionInfluence of plate tectonics for life evolution. Future progress will require conceptual and technical progress in subduction modeling as well as crucial inputs from other disciplines (rheology, phase petrology, seismic tomography, geochemistry, numerical theory, geomorphology, ecology, planetology, astronomy, etc.). As in the past, the multi-physics character of subduction-related processes ensures that numerical modeling will remain one of the key quantitative tools for integration of natural observations, developing and testing new hypotheses, and developing an in-depth understanding of subduction. The review concludes with summarizing key results and outlining 12 future directions in subduction and plate tectonics modeling that will target unresolved issues discussed in the review.
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19

Ledru, P., J. Pons, J. P. Milesi, J. L. Feybesse y V. Johan. "Transcurrent tectonics and polycyclic evolution in the lower proterozoic of Senegal-Mali". Precambrian Research 50, n.º 3-4 (mayo de 1991): 337–54. http://dx.doi.org/10.1016/0301-9268(91)90028-9.

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20

Voosen, Paul. "Ancient crystals show plate tectonics began early". Science 385, n.º 6705 (12 de julio de 2024): 129. http://dx.doi.org/10.1126/science.adr6184.

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21

Chen, Ling, Xu Wang, Xiaofeng Liang, Bo Wan y Lijun Liu. "Subduction tectonics vs. Plume tectonics—Discussion on driving forces for plate motion". Science China Earth Sciences 63, n.º 3 (2 de enero de 2020): 315–28. http://dx.doi.org/10.1007/s11430-019-9538-2.

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22

Gao, Haiying y Maureen D. Long. "Tectonics and Geodynamics of the Cascadia Subduction Zone". Elements 18, n.º 4 (1 de agosto de 2022): 226–31. http://dx.doi.org/10.2138/gselements.18.4.226.

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The Cascadia subduction zone, where the young and thin oceanic Juan de Fuca plate sinks beneath western North America, represents a thermally hot endmember of global subduction systems. Cascadia exhibits complex and three-dimensional heterogeneities including variable coupling between the overriding and downgoing plates, the amount of water carried within and released by the oceanic plate, flow patterns within the mantle wedge and backarc, and the continuity and depth extent of the subducting slab. While recent research has benefitted from extensive onshore and offshore deployments of geophysical instrumentation, a consensus on many important aspects of Cascadia’s magmatic, tectonic, and geodynamic setting remains elusive.
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23

Kent, Adam J. R. y Josef Dufek. "Cascadia: Subduction and People". Elements 18, n.º 4 (1 de agosto de 2022): 221–25. http://dx.doi.org/10.2138/gselements.18.4.221.

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The well-studied Cascadia subduction zone has enriched our general understanding of global subduction zones. This Elements issue explores the interconnected set of processes that link geodynamics, tectonics, and magmatism at depth and the surface expressions of these processes, which shape the landscape and give rise to natural hazards in the Cascadia region. This issue also addresses the impact of subduction zone processes on human populations using cultural records, and reviews the state of knowledge of Cascadia while highlighting some key outstanding research questions.
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24

UMINO, Susumu. "Tectonics of boninites: Subduction initiation and mantle evolution". Japanese Magazine of Mineralogical and Petrological Sciences 48, n.º 2 (2019): 63–75. http://dx.doi.org/10.2465/gkk.190216.

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25

Aubouin, Jean. "Some aspects of the tectonics of subduction zones". Tectonophysics 160, n.º 1-4 (marzo de 1989): 1–21. http://dx.doi.org/10.1016/0040-1951(89)90381-8.

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26

Riedinger, N., M. E. Torres, E. Screaton, E. A. Solomon, S. Kutterolf, J. Schindlbeck‐Belo, M. J. Formolo, T. W. Lyons y P. Vannucchi. "Interplay of Subduction Tectonics, Sedimentation, and Carbon Cycling". Geochemistry, Geophysics, Geosystems 20, n.º 11 (noviembre de 2019): 4939–55. http://dx.doi.org/10.1029/2019gc008613.

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27

Ellis, Susan y Christopher Beaumont. "Models of convergent boundary tectonics: implications for the interpretation of Lithoprobe data". Canadian Journal of Earth Sciences 36, n.º 10 (1 de octubre de 1999): 1711–41. http://dx.doi.org/10.1139/e99-075.

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Physical models of convergent boundary processes can provide insights into compressional orogens such as those studied by Lithoprobe. We summarize the qualitative tectonic style of a series of models designed to explore behaviour in subduction, collision, and obliquely convergent settings. The model results are represented by a series of diagrams which emphasize the main controls and behaviours in each case. Models are categorized in terms of the three main types of control: B, the boundary conditions assumed to operate on crust from surrounding lithosphere; I, the internal properties such as rheology and temperature distribution; and T, the redistribution of thickened crust or excess mass by gravitational forces (flexural compensation) and by surface processes such as erosion and deposition. The model templates for each setting are used to interpret some of the orogens studied by Lithoprobe, where there are sufficient temporal and spatial data for such a comparison to be meaningful. The purpose is to examine conceptual evolutions proposed by geologists and geophysicists in a process-based way. We compare the evolution of the Cascadia subduction margin with templates for oblique subduction; the eastern Trans-Hudson Orogen with models of the transition from subduction to collision; the Appalachian Transect in Lithoprobe East with models that involve a weak interior ("vise" models); the Torngat and New Quebec orogens with templates of subduction, transition to collision, and vise models; and the evolution of the Abitibi-Opatica granite-greenstone belt with models of subduction and collision. Comparison between models and seismic transects also highlights some of the potential pitfalls in interpreting compressional structures using reflectivity fabric.
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28

Murphy, Finbarr C. "Evidence for late Ordovician amalgamation of volcanogenic terranes in the Iapetus suture zone, eastern Ireland". Transactions of the Royal Society of Edinburgh: Earth Sciences 78, n.º 3 (1987): 153–67. http://dx.doi.org/10.1017/s026359330001107x.

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ABSTRACTA major transcurrent fault in the zone of the Iapetus suture in eastern Ireland separates Ordovician (pre-Ashgill) terranes. The stratigraphy of each terrane belongs to a dismembered volcanic arc system: the northern terrane is characterised by acid plinian eruptions and derivative sediments which are displaced relative to the andesitic southern terrane volcanism. Each was a separate palaeoenvironment with its own lithostratigraphical character and faunal elements which were juxtaposed across the fault. However, the late Ashgill to Silurian sediments in both terranes form part of a regional overstep sequence which links across the suture zone, such that the palaeogeographical contrasts were eliminated by the Silurian. The inference is that the detached terranes were gradually amalgamated by late Ordovician transtensional movements. This occurred when regional scale subduction-related volcanism had ended. Final assembly by early Devonian sinistral transpressive movements juxtaposed a northern terrane, akin to the Lake District/SE Ireland calcalkaline volcanic province, with a southern terrane in the tholeiitic province of eastern Ireland. As distinct from a singular fault trace, the Iapetus suture is regarded as a 100 km wide zone of anastomosing late Caledonian transcurrent faults whose precursors were active during late Ordovician (i.e. Taconic) terrane amalgamation.
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29

Loreto, Maria Filomena. "Editorial of Special Issue “Tectonics and Morphology of Back-Arc Basins”". Geosciences 12, n.º 2 (14 de febrero de 2022): 86. http://dx.doi.org/10.3390/geosciences12020086.

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30

Tibaldi, Alessandro. "The role of transcurrent intra-arc tectonics in the configuration of a volcanic arc". Terra Nova 4, n.º 5 (septiembre de 1992): 567–77. http://dx.doi.org/10.1111/j.1365-3121.1992.tb00598.x.

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31

Bercovici, David, Gerald Schubert y Yanick Ricard. "Abrupt tectonics and rapid slab detachment with grain damage". Proceedings of the National Academy of Sciences 112, n.º 5 (20 de enero de 2015): 1287–91. http://dx.doi.org/10.1073/pnas.1415473112.

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A simple model for necking and detachment of subducting slabs is developed to include the coupling between grain-sensitive rheology and grain-size evolution with damage. Necking is triggered by thickened buoyant crust entrained into a subduction zone, in which case grain damage accelerates necking and allows for relatively rapid slab detachment, i.e., within 1 My, depending on the size of the crustal plug. Thick continental crustal plugs can cause rapid necking while smaller plugs characteristic of ocean plateaux cause slower necking; oceanic lithosphere with normal or slightly thickened crust subducts without necking. The model potentially explains how large plateaux or continental crust drawn into subduction zones can cause slab loss and rapid changes in plate motion and/or induce abrupt continental rebound.
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32

Dilek, Yildirim y Limei Tang. "Magmatic record of the Mesozoic geology of Hainan Island and its implications for the Mesozoic tectonomagmatic evolution of SE China: effects of slab geometry and dynamics in continental tectonics". Geological Magazine 158, n.º 1 (10 de diciembre de 2020): 118–42. http://dx.doi.org/10.1017/s0016756820001211.

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AbstractOur field-based geochemical studies of the Triassic, Jurassic and Cretaceous granitoids on Hainan Island indicate that their magmas had different geochemical affinities, changing from alkaline in the Triassic through ocean island basalt (OIB) in the Jurassic, to calc-alkaline in the Cretaceous. We show that these changes in the geochemical affinities of the Mesozoic granitoids on Hainan and in SE China reflect different melt sources and melt evolution patterns through time. Our new geodynamic model suggests that: (1) Triassic geology was controlled by flat-slab subduction of the palaeo-Pacific plate beneath SE China. This slab dynamics resulted in strong coupling between the lower and upper plates, causing push-over tectonics and contractional deformation in SE China. Flat subduction-induced edge flow and aesthenospheric uprising led to the production of high-K granites, syenites and mafic rocks. (2) Slab foundering, accelerated subduction rates and subduction hinge retreat in the Early Jurassic caused rapid rollback of the downgoing slab. Strong decoupling of the upper and lower plates resulted in pull-away tectonics, producing extensional deformation in SE China. Decompression melting of the upwelling aesthenosphere produced OIB-type melts, which interacted with the subcontinental lithospheric mantle (SCLM) to form A- and I-type granitoids. (3) Segmentation of the palaeo-Pacific plate in the Early Cretaceous resulted in steeply dipping slabs and their faster rollback, facilitating lithospheric-scale extension and oceanward migration of calc-alkaline magmatism. This extensional deformation played a significant role in the formation of metamorphic core complexes, widespread crustal melting and development of a Basin and Range-type tectonics and landscape evolution in SE China.
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33

Ueda, ayato. "Forearc tectonics and solid material circulation during seamounts subduction". Journal of the Geological Society of Japan 113, Supplement (2007): S137—S152. http://dx.doi.org/10.5575/geosoc.113.s137.

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34

KIMURA, Toshio. "Subduction Tectonics ; with Special Reference to the Japanese Islands". Journal of Geography (Chigaku Zasshi) 95, n.º 7 (1987): 463–71. http://dx.doi.org/10.5026/jgeography.95.7_463.

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35

Byrne, D. B., G. Suarez y W. R. McCann. "Muertos Trough subduction—microplate tectonics in the northern Caribbean?" Nature 317, n.º 6036 (octubre de 1985): 420–21. http://dx.doi.org/10.1038/317420a0.

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36

CLARKE, S. H. y G. A. CARVER. "Late Holocene Tectonics and Paleoseismicity, Southern Cascadia Subduction Zone". Science 255, n.º 5041 (10 de enero de 1992): 188–92. http://dx.doi.org/10.1126/science.255.5041.188.

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37

Replumaz, Anne, Fabio Antonio Capitanio, Stéphane Guillot, Ana M. Negredo y Antonio Villaseñor. "The coupling of Indian subduction and Asian continental tectonics". Gondwana Research 26, n.º 2 (septiembre de 2014): 608–26. http://dx.doi.org/10.1016/j.gr.2014.04.003.

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38

ICHIHARA, Mie, Claudia ADAM, Valérie VIDAL, Pablo GROSSE, Kenji MIBE y Yuji ORIHASHI. "Dots-and-Lines Approach to Subduction Volcanism and Tectonics". Journal of Geography (Chigaku Zasshi) 126, n.º 2 (2017): 181–93. http://dx.doi.org/10.5026/jgeography.126.181.

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39

Foley, Bradford J. "The dependence of planetary tectonics on mantle thermal state: applications to early Earth evolution". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, n.º 2132 (octubre de 2018): 20170409. http://dx.doi.org/10.1098/rsta.2017.0409.

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For plate tectonics to operate on a planet, mantle convective forces must be capable of forming weak, localized shear zones in the lithosphere that act as plate boundaries. Otherwise, a planet's mantle will convect in a stagnant lid regime, where subduction and plate motions are absent. Thus, when and how plate tectonics initiated on the Earth is intrinsically tied to the ability of mantle convection to form plate boundaries; however, the physics behind this process are still uncertain. Most mantle convection models have employed a simple pseudoplastic model of the lithosphere, where the lithosphere ‘fails’ and develops a mobile lid when stresses in the lithosphere reach the prescribed yield stress. With pseudoplasticity high mantle temperatures and high rates of internal heating, conditions relevant for the early Earth, impede plate boundary formation by decreasing lithospheric stresses, and hence favour a stagnant lid for the early Earth. However, when a model for shear zone formation based on grain size reduction is used, early Earth thermal conditions do not favour a stagnant lid. While lithosphere stress drops with increasing mantle temperature or heat production rate, the deformational work, which drives grain size reduction, increases. Thus, the ability of convection to form weak plate boundaries is not impeded by early Earth thermal conditions. However, mantle thermal state does change the style of subduction and lithosphere mobility; high mantle temperatures lead to a more sluggish, drip-like style of subduction. This ‘sluggish lid’ convection may be able to explain many of the key observations of early Earth crust formation processes preserved in the geologic record. Moreover, this work highlights the importance of understanding the microphysics of plate boundary formation for assessing early Earth tectonics, as different plate boundary formation mechanisms are influenced by mantle thermal state in fundamentally different ways.This article is part of a discussion meeting issue ‘Earth dynamics and the development of plate tectonics’.
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40

Tikoo, Sonia M. y Linda T. Elkins-Tanton. "The fate of water within Earth and super-Earths and implications for plate tectonics". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, n.º 2094 (17 de abril de 2017): 20150394. http://dx.doi.org/10.1098/rsta.2015.0394.

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The Earth is likely to have acquired most of its water during accretion. Internal heat of planetesimals by short-lived radioisotopes would have caused some water loss, but impacts into planetesimals were insufficiently energetic to produce further drying. Water is thought to be critical for the development of plate tectonics, because it lowers viscosities in the asthenosphere, enabling subduction. The following issue persists: if water is necessary for plate tectonics, but subduction itself hydrates the upper mantle, how is the upper mantle initially hydrated? The giant impacts of late accretion created magma lakes and oceans, which degassed during solidification to produce a heavy atmosphere. However, some water would have remained in the mantle, trapped within crystallographic defects in nominally anhydrous minerals. In this paper, we present models demonstrating that processes associated with magma ocean solidification and overturn may segregate sufficient quantities of water within the upper mantle to induce partial melting and produce a damp asthenosphere, thereby facilitating plate tectonics and, in turn, the habitability of Earth-like extrasolar planets. This article is part of the themed issue ‘The origin, history and role of water in the evolution of the inner Solar System’.
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41

Zhou, Xin, Zhong-Hai Li, Taras V. Gerya y Robert J. Stern. "Lateral propagation–induced subduction initiation at passive continental margins controlled by preexisting lithospheric weakness". Science Advances 6, n.º 10 (marzo de 2020): eaaz1048. http://dx.doi.org/10.1126/sciadv.aaz1048.

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Understanding the conditions for forming new subduction zones at passive continental margins is important for understanding plate tectonics and the Wilson cycle. Previous models of subduction initiation (SI) at passive margins generally ignore effects due to the lateral transition from oceanic to continental lithosphere. Here, we use three-dimensional numerical models to study the possibility of propagating convergent plate margins from preexisting intraoceanic subduction zones along passive margins [subduction propagation (SP)]. Three possible regimes are achieved: (i) subducting slab tearing along a STEP fault, (ii) lateral propagation–induced SI at passive margin, and (iii) aborted SI with slab break-off. Passive margin SP requires a significant preexisting lithospheric weakness and a strong slab pull from neighboring subduction zones. The Atlantic passive margin to the north of Lesser Antilles could experience SP if it has a notable lithospheric weakness. In contrast, the Scotia subduction zone in the Southern Atlantic will most likely not propagate laterally.
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42

Bauve, Victorien, Romain Plateaux, Yann Rolland, Guillaume Sanchez, Nicole Bethoux, Bertrand Delouis y Romain Darnault. "Long-lasting transcurrent tectonics in SW Alps evidenced by Neogene to present-day stress fields". Tectonophysics 621 (mayo de 2014): 85–100. http://dx.doi.org/10.1016/j.tecto.2014.02.006.

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43

Craw, Dave, Tania M. King, Graham A. McCulloch, Phaedra Upton y Jonathan M. Waters. "Biological evidence constraining river drainage evolution across a subduction-transcurrent plate boundary transition, New Zealand". Geomorphology 336 (julio de 2019): 119–32. http://dx.doi.org/10.1016/j.geomorph.2019.03.032.

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44

Dilek, Yildirim, Minella Shallo y Harald Furnes. "Rift-Drift, Seafloor Spreading, and Subduction Tectonics of Albanian Ophiolites". International Geology Review 47, n.º 2 (febrero de 2005): 147–76. http://dx.doi.org/10.2747/0020-6814.47.2.147.

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45

Ellis, Susan. "Forces driving continental collision: Reconciling indentation and mantle subduction tectonics". Geology 24, n.º 8 (1996): 699. http://dx.doi.org/10.1130/0091-7613(1996)024<0699:fdccri>2.3.co;2.

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46

Kimura, Gaku. "Oblique subduction and collision: Forearc tectonics of the Kuril arc". Geology 14, n.º 5 (1986): 404. http://dx.doi.org/10.1130/0091-7613(1986)14<404:osacft>2.0.co;2.

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47

Dong, Yunpeng, Shengsi Sun, Zhao Yang, Xiaoming Liu, Feifei Zhang, Wei Li, Bin Cheng, Dengfeng He y Guowei Zhang. "Neoproterozoic subduction-accretionary tectonics of the South Qinling Belt, China". Precambrian Research 293 (mayo de 2017): 73–90. http://dx.doi.org/10.1016/j.precamres.2017.02.015.

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48

Zheng, YongFei, Kai Ye y LiFei Zhang. "Developing the plate tectonics from oceanic subduction to continental collision". Science Bulletin 54, n.º 15 (agosto de 2009): 2549–55. http://dx.doi.org/10.1007/s11434-009-0464-0.

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49

Keppler, Hans, Eiji Ohtani y Xiaozhi Yang. "The Subduction of Hydrogen: Deep Water Cycling, Induced Seismicity, and Plate Tectonics". Elements 20, n.º 4 (1 de agosto de 2024): 229–34. http://dx.doi.org/10.2138/gselements.20.4.229.

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The dynamic equilibrium between mantle degassing and water recycling in subduction zones controls the variation of sea level in deep geologic time, as well as the size of Earth’s interior hydrogen reservoir. While the principles of water transport and water release by common hydrous minerals in the subducted crust are relatively well understood, the importance of deep serpentinization of the slab, the contribution of nominally anhydrous minerals and dense hydrous magnesium silicates to water transport, and the mechanisms of water subduction into the lower mantle are still subjects of active research. A quantitative understanding of these processes is required to constrain the evolution of Earth’s deep water cycle through geologic time and the role of water in stabilizing plate tectonics.
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50

Hidayat, Edi, Dicky Muslim, Dimas Aryo Wibowo, Eko Puswanto, Sonny Aribowo, Asep Mulyono y Yayat Sudrajat. "Appraisal of active tectonics in Karangsambung Amphitheater: Insights from DEM-derived geomorphic indices and geological data". IOP Conference Series: Earth and Environmental Science 1314, n.º 1 (1 de marzo de 2024): 012092. http://dx.doi.org/10.1088/1755-1315/1314/1/012092.

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Abstract The morphology of the Karangsambung area shows a unique form, namely the morphology of the amphitheater. This area results from the complexity of tectonic, erosion, and depositional processes. The active tectonics in this region greatly influence the drainage system and geomorphic expression. The study area provides evidence of subduction in Java. It is an ideal natural laboratory for studying evidence of tectonic activity due to the subduction of the Indo-Australian plate with the Eurasian plate during the Cretaceous period. We evaluated active tectonics using the DEM to assess the characteristics of the geomorphic index. The results obtained from these indices were combined to produce an index of relative active tectonics (IRAT) using GIS. The average of the seven geomorphic indices measured was used to evaluate the distribution of relative tectonic activity in the study area. We defined four classes to determine the relative level of tectonic activity: class 1: very high (1.0 ≤ IRAT < 1.5); class 2: high (1.5 ≥ IRAT < 2); grade 3: moderate (2 ≥ IRAT < 2.5); and grade 4: low (2.5 ≥ IRAT). The results show that the study area was strongly deformed and was influenced by tectonic activity. Landsat imagery, DEM, and field observations also proved the presence of active tectonics in the form of uplift accompanied by high vertical erosion forming pointed hills with narrow valleys, the exposure of Cretaceous-aged rocks, amphitheater morphology, and the uplift of river terraces. The indicative IRAT values were consistent with the relative uplift levels, landforms, and geology.
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