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1

Royden, Leigh, i Claudio Faccenna. "Subduction Orogeny and the Late Cenozoic Evolution of the Mediterranean Arcs". Annual Review of Earth and Planetary Sciences 46, nr 1 (30.05.2018): 261–89. http://dx.doi.org/10.1146/annurev-earth-060115-012419.

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The Late Cenozoic tectonic evolution of the Mediterranean region, which is sandwiched between the converging African and European continents, is dominated by the process of subduction orogeny. Subduction orogeny occurs where localized subduction, driven by negative slab buoyancy, is more rapid than the convergence rate of the bounding plates; it is commonly developed in zones of early or incomplete continental collision. Subduction orogens can be distinguished from collisional orogens on the basis of driving mechanism, tectonic setting, and geologic expression. Three distinct Late Cenozoic subduction orogens can be identified in the Mediterranean region, making up the Western Mediterranean (Apennine, external Betic, Maghebride, Rif), Central Mediterranean (Carpathian), and Eastern Mediterranean (southern Dinaride, external Hellenide, external Tauride) Arcs. The Late Cenozoic evolution of these orogens, described in this article, is best understood in light of the processes that govern subduction orogeny and depends strongly on the buoyancy of the locally subducting lithosphere; it is thus strongly related to paleogeography. Because the slow (4–10 mm/yr) convergence rate between Africa and Eurasia has preserved the early collisional environment, and associated tectonism, for tens of millions of years, the Mediterranean region provides an excellent opportunity to elucidate the dynamic and kinematic processes of subduction orogeny and to better understand how these processes operate in other orogenic systems.
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Beaumont, Christopher, Rebecca Jamieson i Mai Nguyen. "Models of large, hot orogens containing a collage of reworked and accreted terranesThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, nr 4 (kwiecień 2010): 485–515. http://dx.doi.org/10.1139/e10-002.

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We describe a classification scheme for orogens using Temperature–Magnitude (T–M) diagrams and use this framework for modelling large, hot orogens that evolve in continents comprising cratonic nuclei bordered by a series of juvenile accreted, reworked, and metamorphosed terranes. Modelling the complete evolution of an orogen is difficult, particularly large orogens with multiple orogenic phases. Early phases during which a continent is assembled produce a tectonic and metamorphic fabric that needs to be taken into account when modelling the main collisional orogeny. This inherited fabric is represented in a simple way in models described here by a series of lower crustal blocks that are arranged to be systematically stronger toward the cratonic continental interiors. We investigate how this fabric influences the development of the model orogen during the main collisional phase using upper-mantle-scale (UMS) and crustal-scale (CS) finite element models. The models exhibit a diachronous three-phase evolution: crustal thickening, thermal incubation, and lower crustal indentation. The UMS and CS models are shown to give comparable results in regard to crustal deformation. The UMS models exhibit additional features including single- and double-slab breakoffs and corresponding episodes of uplift and gravitational spreading within the orogenic crust. Protracted postconvergent gravitational spreading of the hot, decoupled crust is also demonstrated. Lastly, we demonstrate the application of this type of model to natural orogens, the Grenville orogen in western Ontario and the southern Canadian Cordillera, and in terms of the T–M diagram.
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Li, Hong Kui, Yi Fan Li, Lu Yi Li, Chuan Yuan Zhuo, Ke Geng i Tai Tao Liang. "Discussion about Gold Ores Mineralization of Collision-Type Orogeny in the East of Shandong". Applied Mechanics and Materials 353-356 (sierpień 2013): 1249–62. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.1249.

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The mineralization of collision orogeny is an important part of continental dynamics. For the process of continental dynamics of Shandong, adoption of tectonic facies mapping is main carrier and specific expression form to these researches such as divergence of continental mass, convergence, collision and orogeny. Shandong tectonic facies mapping of 1:500000 scale worked out by author shows that there are two very important events of collision orogeny in Mesozoic this areaIndochina and Yanshan collision orogeny. The Indochina orogeny is mainly characterized as subduction from Yangtze to North China Plates, based on which Sulu high-ultra high pressure zone of metamorphism, syn-orogenic granite and post-orogenic high alkali sinaite are formed. Continental dynamics environment of the Yanshan orogeny derives from transformation from Central Asia-Tethys tectonic domain to marginal-Pacific tectonic domain and subduction of Pacific plates, and it appears as three orogenys and three stretching in the east of Shandong. Magmatic rocks of orogeny related with gold ores can be divided into four combinations as follows: Linglong gneissic granite of the early orogenic period (J3), Guojialing granodiorite-granite of the middle orogenic period (K1), Weideshan diorite-granodiorite-granite of the late orogenic period (K1) and A-type Laoshan geode parlkaline alkali granitesyenogranite of the post orogenic period. For combination of Guojialing granodiorite-granite of the middle orogenic period, SHRIMP U-Pb ages concentrate in 130~126Ma, which are closely related with emplacement of gold ores, and formed ages of gold ores this area concentrate in 115~120Ma, which basically stand for the age of main mineralization period. Polymetallic ores are related with combination of Weideshan diorite-granodiorite-granite of the late orogenic period, and it was also the superimposed mineralization period in the east of Shandong. Tectonics-magma activities and gold ores mineralization are controlled by interaction of three tectonic domains that are tethys, Paleo-Asian Ocean and Pacific. Dynamics background of gold ores this area is transition of tectonic system and lithospheric thinning in Mesozoic, which is related with collision of North China and Yangtze Plates and subduction of Pacific Plates.
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Manatschal, Gianreto, Pauline Chenin, Rodolphe Lescoutre, Jordi Miró, Patricia Cadenas, Nicolas Saspiturry, Emmanuel Masini i in. "The role of inheritance in forming rifts and rifted margins and building collisional orogens: a Biscay-Pyrenean perspective". BSGF - Earth Sciences Bulletin 192 (2021): 55. http://dx.doi.org/10.1051/bsgf/2021042.

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A long-standing challenge in tectonics is to evaluate the role of inheritance and define the initial conditions of a geodynamic system, which are prerequisites to understand and model its evolution with some accuracy. Here we revisit the concept of “inheritance” by distinguishing “interface shape inheritance”, which includes the transient thermal state and gravitational potential energy, and “persisting inheritance”, which encompasses long-lasting structural and compositional inheritance. This new approach allows us to investigate, at each stage of a Wilson Cycle, the interplay between inheritance (innate/“genetic code”) and the physical processes at play (extension/compression, magmatism etc.). The aim of this paper is to provide a conceptual framework that integrates the role of inheritance in the study of rifts, rifted margins and collisional orogens based on the work done in the OROGEN project, which focuses on the Biscay-Pyrenean system. The Biscay-Pyrenean rift system resulted from a multistage rift evolution that developed over a complex lithosphere pre-structured by the Variscan orogenic cycle. There is a general agreement that the Pyrenean-Cantabrian orogen resulted from the reactivation of an increasingly mature rift system along-strike, ranging from mature rifted margins in the west to an immature and segmented hyperextended rift in the east. However, different models have been proposed to explain the preceding rifting and its influence on the subsequent reactivation. Results from the OROGEN project highlight the sequential reactivation of rift-inherited decoupling horizons and identify the specific role of exhumed mantle, hyperextended and necking domains during compressional reactivation. They also highlight the contrasting fate of rift segment centres versus segment boundaries during convergence, explaining the non-cylindricity of internal parts of collisional orogens. Results from the OROGEN project also suggest that the role of inheritance is more important during the initial stages of collision, which may explain the higher complexity of internal parts of orogenic systems with respect to their external parts. In contrast, when the system involved in the orogeny is more mature, the orogenic evolution is mostly controlled by first-order physical processes as described in the Coulomb Wedge theory, for instance. This may account for the simpler and more continuous architecture of external parts of collisional orogens and may also explain why most numerical models can reproduce mature orogenic architectures with a better accuracy compared to those of initial collisional stages. The new concepts developed from the OROGEN research are now ready to be tested at other orogenic systems that result from the reactivation of rifted margins, such as the Alps, the Colombian cordilleras and the Caribbean, Taiwan, Oman, Zagros or Timor.
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Stephens, Michael B., i Carl-Henric Wahlgren. "Chapter 17 Accretionary orogens reworked in an overriding plate setting during protracted continent–continent collision, Sveconorwegian orogen, southwestern Sweden". Geological Society, London, Memoirs 50, nr 1 (2020): 435–48. http://dx.doi.org/10.1144/m50-2018-83.

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AbstractThe Eastern Segment in the Sveconorwegian orogen, southwestern Sweden, is dominated by 2.0–1.8, 1.7 and 1.5–1.4 Ga crust; and the overlying Idefjorden terrane by 1.6–1.5 Ga crust. Assuming reorganization of a subduction system prior to 1.5–1.4 Ga and applying a sinistral transpressive component of disruption during the subsequent Sveconorwegian orogeny (1.1–0.9 Ga), the Idefjorden terrane is inferred to be indigenous outboard rather than exotic with respect to the continental plate Fennoscandia (Baltica). The geological record then records successive westwards shift of accretionary orogens along a convergent plate boundary for at least 500 million years. Sveconorwegian foreland-younging tectonic cycles at c. 1.05 (or older)–1.02 Ga (Idefjorden terrane) and at c. 0.99–0.95 Ga (Eastern Segment) prevailed. Crustal thickening and exhumation during oblique convergence preceded migmatization, magmatic activity and a changeover to an extensional regime, possibly triggered by delamination of continental lithosphere, in each cycle. Convergence after 0.95 Ga involved antiformal doming with extensional deformation at higher crustal levels (Eastern Segment) and continued magmatic activity (Idefjorden terrane). An overriding plate setting is inferred during either accretionary orogeny or, more probably, protracted continent–continent collision. Continuity of the erosional fronts in the Grenville and Sveconorwegian orogens is questioned.
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6

Zhimulev, F. I., E. V. Vetrov, I. S. Novikov, G. Van Ranst, S. Nachtergaele, S. A. Dokashenko i J. De Grave. "Mesozoic Intracontinental Orogeny in the Tectonic History of the Kolyvan’– Tomsk Folded Zone (Southern Siberia): a Synthesis of Geological Data and results of Apatite Fission Track Analysis". Russian Geology and Geophysics 62, nr 9 (1.09.2021): 1006–20. http://dx.doi.org/10.2113/rgg20204172.

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Abstract —The Kolyvan’–Tomsk folded zone (KTFZ) is a late Permian collisional orogen in the northwestern section of the Central Asian Orogenic Belt. The Mesozoic history of the KTFZ area includes Late Triassic–Early Jurassic and Late Jurassic–Early Cretaceous orogenic events. The earlier event produced narrow deep half-ramp basins filled with Early–Middle Jurassic molasse south of the KTFZ, and the later activity rejuvenated the Tomsk thrust fault, whereby the KTFZ Paleozoic rocks were thrust over the Early–Middle Jurassic basin sediments. The Mesozoic orogenic events induced erosion and the ensuing exposure of granitoids (Barlak complex) that were emplaced in a within-plate context after the Permian collisional orogeny. Both events were most likely associated with ocean closure, i.e., the Paleothetys Ocean in the Late Triassic–Early Jurassic and the Mongol–Okhotsk Ocean in the Late Jurassic–Early Cretaceous. The apatite fission track (AFT) ages of granitoids from the Ob’ complex in the KTFZ range between ~120 and 100 Ma (the Aptian and the Albian). The rocks with Early Cretaceous AFT ages were exhumed as a result of denudation and peneplanation of the Early Cretaceous orogeny, which produced a vast Late Cretaceous–Paleogene planation surface. The tectonic pattern of the two orogenic events, although being different in details, generally inherited the late Paleozoic primary collisional structure of the Kolyvan’–Tomsk zone.
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Slagstad, Trond, Michael A. Hamilton, Rebecca A. Jamieson i Nicholas G. Culshaw. "Timing and duration of melting in the mid orogenic crust: Constraints from U–Pb (SHRIMP) data, Muskoka and Shawanaga domains, Grenville Province, Ontario". Canadian Journal of Earth Sciences 41, nr 11 (1.11.2004): 1339–65. http://dx.doi.org/10.1139/e04-068.

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The Central Gneiss Belt in the Grenville Province, Ontario, exposes metaplutonic rocks, orthogneisses, and minor paragneisses that were deformed and metamorphosed at crustal depths of 20–35 km during the Mesoproterozoic Grenvillian orogeny. We present sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon data from eight samples of migmatitic orthogneiss, granite, and pegmatite from the Muskoka and Shawanaga domains that constrain the age and duration of partial melting in the mid orogenic crust. Our results support earlier interpretations that the protoliths to these migmatitic orthogneisses formed at ca. 1450 Ma. Emplacement and crystallization of granite and pegmatite in the Shawanaga domain took place at ca. 1089 Ma, apparently coevally with deformation and high-grade metamorphism. Leucosomes in the Muskoka and Shawanaga domains yield ages of 1067 and 1047 Ma, respectively, interpreted as the ages of melt crystallization. The geochronological data and field observations suggest that melt was present at the mid-crustal level of the Grenville orogen during a significant part of its deformational history, probably at least 20–30 million years. By analogy with modern orogens, the amount and duration of melting observed in the Muskoka and Shawanaga domains may have had an impact on the orogenic evolution of the area.
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Gonzalez, Joseph P., Suzanne L. Baldwin, Jay B. Thomas, William O. Nachlas i Paul G. Fitzgerald. "Evidence for ultrahigh-pressure metamorphism discovered in the Appalachian orogen". Geology 48, nr 10 (19.06.2020): 947–51. http://dx.doi.org/10.1130/g47507.1.

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Abstract The Appalachian orogen has long been enigmatic because, compared to other parts of the Paleozoic orogens that formed following the subduction of the Iapetus Ocean, direct evidence for ultrahigh-pressure (UHP) metamorphism has never been found. We report the first discovery of coesite in the Appalachian orogen in a metapelite from the mid-Ordovician (Taconic orogeny) Tillotson Peak Complex in Vermont (USA). Relict coesite occurs within a bimineralic SiO2 inclusion in garnet. In situ elastic barometry and trace-element thermometry allow reconstruction of the garnet growth history during prograde metamorphism. The data are interpreted to indicate garnet nucleation and crystallization during blueschist- to eclogite-facies subduction zone metamorphism, followed by garnet rim growth at UHP conditions of > 28 kbar and > 530 ° C. Results provide the first direct evidence that rocks of the Appalachian orogen underwent UHP metamorphism to depths of > 75 km and warrant future studies that constrain the extent of UHP metamorphism.
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Cook, D. G., i B. C. MacLean. "The intracratonic Paleoproterozoic Forward orogeny, and implications for regional correlations, Northwest Territories, Canada". Canadian Journal of Earth Sciences 32, nr 11 (1.11.1995): 1991–2008. http://dx.doi.org/10.1139/e95-152.

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Reflection seismic data from the Colville Hills and Anderson Plain document an intracratonic compressional event, herein named the Forward orogeny, which affected strata considered equivalent to the >1663 Ma Hornby Bay Group outcropping on Coppermine Homocline. Forward orogeny structures were peneplaned and unconformably overlain by strata considered equivalent to the >1267 Ma Dismal Lakes Group. A comparable tectonic history is recorded in the exposed rocks of Coppermine Homocline to the east. Structural orientations indicate a general northwest–southeast direction of maximum compression during an early phase and a more west–east direction in a later phase. Regional sequence A of G.M. Young and co-workers is subdivided into preorogenic sequence A1 (Hornby Bay and equivalents), and postorogenic sequences A2 (Dismal Lakes and equivalents) and A3 (Coppermine River group and equivalents). The Forward orogeny, dated as approximately 1663 Ma (the age of the syntectonic Kaertok Formation on Coppermine Homocline), is not related to the 1.84–1.9 Ga Wopmay Orogen. Relationships between the Forward orogeny and the Racklan orogeny, in the Wernecke and Ogilvie mountains, remain unresolved because the age of the Racklan is uncertain.
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Wilkins, Colin, i Mike Quayle. "Structural Control of High-Grade Gold Shoots at the Reward Mine, Hill End, New South Wales, Australia". Economic Geology 116, nr 4 (1.06.2021): 909–35. http://dx.doi.org/10.5382/econgeo.4807.

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Abstract The Reward mine at Hill End hosts structurally controlled orogenic gold mineralization in moderately S plunging, high-grade gold shoots located at the intersection between a late, steeply W dipping reverse fault zone and E-dipping, bedding-parallel, laminated quartz veins (the Paxton’s vein system). The mineralized bedding-parallel veins are contained within the middle Silurian to Middle Devonian age, turbidite-dominated Hill End trough forming part of the Lachlan orogen in New South Wales. The Hill End trough was deformed in the Middle Devonian (Tabberabberan orogeny), forming tight, N-S–trending, macroscopic D2 folds (Hill End anticline) with S2 slaty cleavage and associated bedding-parallel veins. Structural analysis indicates that the D2 flexural-slip folding mechanism formed bedding-parallel movement zones that contained flexural-slip duplexes, bedding-parallel veins, and saddle reefs in the fold hinges. Bedding-parallel veins are concentrated in weak, narrow shale beds between competent sandstones with dip angles up to 70° indicating that the flexural slip along bedding occurred on unfavorably oriented planes until fold lockup. Gold was precipitated during folding, with fluid-flow concentrated along bedding, as fold limbs rotated, and hosted by bedding-parallel veins and associated structures. However, the gold is sporadically developed, often with subeconomic grades, and is associated with quartz, muscovite, chlorite, carbonates, pyrrhotite, and pyrite. East-west shortening of the Hill End trough resumed during the Late Devonian to early Carboniferous (Kanimblan orogeny), producing a series of steeply W dipping reverse faults that crosscut the eastern limb of the Hill End anticline. Where W-dipping reverse faults intersected major E-dipping bedding-parallel veins, gold (now associated with galena and sphalerite) was precipitated in a network of brittle fractures contained within the veins, forming moderately S plunging, high-grade gold shoots. Only where major bedding-parallel veins were intersected, displaced, and fractured by late W-dipping reverse faults is there a potential for localization of high-grade gold shoots (>10 g/t). A revised structural history for the Hill End area not only explains the location of gold shoots in the Reward mine but allows previous geochemical, dating, and isotope studies to be better understood, with the discordant W-dipping reverse faults likely acting as feeder structures introducing gold-bearing fluids sourced within deeply buried Ordovician volcanic units below the Hill End trough. A comparison is made between gold mineralization, structural style, and timing at Hill End in the eastern Lachlan orogen with the gold deposits of Victoria, in the western Lachlan orogen. Structural styles are similar where gold mineralization is formed during folding and reverse faulting during periods of regional east-west shortening. However, at Hill End, flexural-slip folding-related weakly mineralized bedding-parallel veins are reactivated to a lesser degree once folds lock up (cf. the Bendigo zone deposits in Victoria) due to the earlier effects of fold-related flattening and boudinage. The second stage of gold mineralization was formed by an array of crosscutting, steeply W dipping reverse faults fracturing preexisting bedding-parallel veins that developed high-grade gold shoots. Deformation and gold mineralization in the western Lachlan orogen started in the Late Ordovician to middle Silurian Benambran orogeny and continued with more deposits forming in the Bindian (Early Devonian) and Tabberabberan (late Early-Middle Devonian) orogenies. This differs from the Hill End trough in the eastern Lachlan orogen, where deformation and mineralization started in the Tabberabberan orogeny and culminated with the formation of high-grade gold shoots at Hill End during renewed compression in the early Carboniferous Kanimblan orogeny.
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Hynes, Andrew, i Toby Rivers. "Protracted continental collision — evidence from the Grenville OrogenThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, nr 5 (maj 2010): 591–620. http://dx.doi.org/10.1139/e10-003.

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The Grenville Orogen in North America is interpreted to have resulted from collision between Laurentia and another continent, probably Amazonia, at ca. 1100 Ma. The exposed segment of the orogen was derived largely from reworked Archean to Paleoproterozoic Laurentian crust, products of a long-lived Mesoproterozoic continental-margin arc and associated back arc, and remnants of one or more accreted mid-Mesoproterozoic island-arc terranes. A potential suture, preserved in Grenvillian inliers of the southeastern USA, may separate rocks of Laurentian and Amazonian affinities. The Grenvillian Orogeny lasted more than 100 million years. Much of the interior Grenville Province, with peak metamorphism at ca. 1090–1020 Ma, consists of uppermost amphibolite- to granulite-facies rocks metamorphosed at depths of ca. 30 km, but areas of lower crustal, eclogite-facies nappes metamorphosed at 50–60 km depth also occur and an orogenic lid that largely escaped Grenvillian metamorphism is preserved locally. Overall, deformation and regional metamorphism migrated sequentially to the northwest into the Laurentian craton, with the youngest contractional structures in the northwestern part of the orogen at ca. 1000–980 Ma. The North American lithospheric root extends across part of the Grenville Orogen, where it may have been produced by depletion of sub-continental lithospheric mantle beneath the long-lived Laurentian-margin Mesoproterozoic subduction zone. Both the Grenville Orogen and the Himalaya–Tibet Orogen have northern margins characterized by long-lived subduction before continental collision and protracted convergence following collision. Both exhibit cratonward-propagating thrusting. In the Himalaya–Tibet Orogen, however, the pre-collisional Eurasian-margin arc is high in the structural stack, whereas in the Grenville Orogen, the pre-collisional continental-margin arc is low in the structural stack. We interpret this difference as due to subduction reversal in the Grenville case shortly before collision, so that the continental-margin arc became the lower plate during the ensuing orogeny. The structurally low position of the warm, extended Laurentian crust probably contributed significantly to the ductility of lower and mid-crustal Grenvillian rocks.
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Dimitrescu, Radu. "Considerations on the Variscides of Romania". Geologica Balcanica 23, nr 2 (30.04.1993): 73–80. http://dx.doi.org/10.52321/geolbalc.23.2.73.

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From the proposed analysis of two geotraverses, Moesian Platform – South Carpathians and East European Platform – East Carpathians – Apuseni Mountains, it seems that the south-eastern boundary of the Variscan orogen coincided with the present south-eastern boundary of the Alpine orogen. A corollary of this fact could be that the Palaeozoic basement of the Carpathian foreland played the same role of foreland at the time of the Variscan orogeny. Herefrom, the polarity of the Variscides on which the Carpathians are built may be inferred. The mafic initial tension magmatism of the Variscan orogeny was manifested from the Silurian up to the Early Carboniferous in the present territory of the Carpathian orogen. This magmatism became bimodal in the Early Carboniferous. An exclusively acid character of this Early Carboniferous magmatism occur only in the Northern Poiana Ruscă and in the Rapolt massif. In the relative hinterland of the Variscides underlying the Carpathian orogen, an internal zone of carbonatic-platform formations of Devonian and Carboniferous age can bе outline.
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MOUMBLOW, R. M., G. A. ARCURI, A. P. DICKIN i C. F. GOWER. "Nd and Pb isotope mapping of crustal domains within the Makkovik Province, Labrador". Geological Magazine 156, nr 5 (3.04.2018): 833–48. http://dx.doi.org/10.1017/s0016756818000195.

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AbstractThe Makkovik Province of eastern Labrador represents part of an accretionary orogen active during an early stage in the development of the Palaeoproterozoic southern Laurentian continental margin. New Nd isotope data for the eastern Makkovik Province suggest that accreted juvenile Makkovik crust was generated in the Cape Harrison domain during a single crust-forming event at c. 2.0 Ga. Pb isotope data support this model, and show a strong similarity to radiogenic crustal signatures in the juvenile Palaeoproterozoic crust of the Ketilidian mobile belt of southern Greenland. As previously proposed, an arc accretion event at c. 1.9 Ga triggered subduction-zone reversal and the development of an ensialic arc on the composite margin. After the subduction flip, a temporary release of compressive stress at c. 1.87 Ga led to the development of a retro-arc foreland basin on the downloaded Archean continental edge, forming the Aillik Group. Unlike previous models, a second arc is not envisaged. Instead, a compressive regime at c. 1.82 Ga is attributed to continued ensialic arc plutonism on the existing margin. The tectonic model for the Makkovikian orogeny proposed here is similar to that for the Ketilidian orogeny. Major- and trace-element analyses suggest that much of the magmatism in the Makkovik orogen results from post-accretionary ensialic arc activity, and that few vestiges remain of the original accreted volcanic arc. This pattern of arc accretion and intense post-accretion reworking is common to many accretionary orogens, such as the South American Andes and North American Cordillera.
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Balintoni, Ion, Constantin Balica, Antoneta Seghedi i Mihai Ducea. "Peri-Amazonian provenance of the Central Dobrogea terrane (Romania) attested by U/Pb detrital zircon age patterns". Geologica Carpathica 62, nr 4 (1.08.2011): 299–307. http://dx.doi.org/10.2478/v10096-011-0023-x.

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Peri-Amazonian provenance of the Central Dobrogea terrane (Romania) attested by U/Pb detrital zircon age patterns The Central Dobrogea Shield is a part of the Moesia, a Paleozoic composite terrane located southward of the North Dobrogea Alpine orogen. The two geological units are separated from each other by a trans-lithospheric discontinuity, the Peceneaga-Camena transform fault. Along this fault, remnants of a Variscan orogen (i.e. North Dobrogea), recycled during the Alpine orogeny come in contact with two lithological entities of the Central Dobrogea Shield, unaffected by the Phanerozoic orogenic events: the Histria Formation, a flysch-like sequence of Ediacaran age very low-grade metamorphosed and its basement, the medium-grade metamorphosed Altîn Tepe sequence. Southward, along the reverse hidden Palazu fault, the Histria Formation meets South Dobrogea, formed of quite different geological formations. Detrital zircon from the Histria Formation yielded U/Pb LA ICP MS ages that show provenance patterns typical of peri-Amazonian terranes. Such terranes were sourced by orogens ranging from Paleoarchean to Neoproterozoic. The ages between 750 and 600 Ma differentiate the Amazonian sources from the Baltican and Laurentian sources, since they are lacking from the last ones. The youngest ages of 587 and 584 Ma suggest for the Histria Formation a maximum late Ediacaran deposition age. At the same time, the continuity of the Ordovician sediments over the Palazu fault revealed by drill-cores favours a Cambrian junction between Central and South Dobrogea.
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Koroteev, V. A., V. M. Necheukhin, V. A. Dushin i E. N. Volchek. "Formation features and a geodynamic map of the Ural-Timan-Paleo-Asian segment of Eurasia". LITHOSPHERE (Russia) 20, nr 5 (30.10.2020): 607–29. http://dx.doi.org/10.24930/1681-9004-2020-20-5-607-629.

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Research subject. This article is devoted to the formation features of the Ural-Timan-Paleo-Asian segment of Eurasia. Materials and methods. The research was based on the authors’ data and those obtained following a review of available publications on the geology of segmentation. The Timan region was investigated using the geological information obtained by V.G. Olovyanishnikov.Results. A geodynamic map of the Ural-Timan-Paleo-Asian segment with a scale of 1 : 2 500 000 was compiled, which allowed further research into the structure and formation of the north-western part of the Eurasian area. This part was found to be mostly composed of geodynamic associations of orogens, orogenic systems and orogenic belts of the Upper Proterozoic (Riphean) and Paleozoic time intervals, as well as by elements of the Mesozoic-Cenozoic neoplate. These processes were supplemented by the formation of tectonic systems of superimposed depressions and protoplate protrusions. The formation of orogens, orogenic systems and orogenic belts is associated with the development and subsequent transformation of paleooceanic basins under the conditions of accretion and collision. The terranes of the ancient continental crust also participated in the formation of the segment’s geodynamic elements, for which a typification scheme was proposed. The articles present new data on the formation conditions of the segment’s orogenic elements and the relationship of the orogeny with global reconstructions, including the problem of closing the surrounding oceanic space.
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Stephens, Michael B. "Chapter 1 Introduction to the lithotectonic framework of Sweden and organization of this Memoir". Geological Society, London, Memoirs 50, nr 1 (2020): 1–15. http://dx.doi.org/10.1144/m50-2019-21.

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AbstractThe solid rock geology of Sweden comprises three principal components: (1) Proterozoic and (locally) Archean rocks belonging to the western part of the Fennoscandian Shield; (2) Phanerozoic and (locally) Neoproterozoic sedimentary cover rocks deposited on top of this ancient crust; and (3) the early to mid-Paleozoic (0.5–0.4 Ga) Caledonide orogen. Earlier compilations have applied different principles for the subdivision of the geology in the Fennoscandian Shield and the Caledonide orogen. A uniform lithotectonic framework has been developed here. Crustal segments affected by orogenesis have been identified and their ages determined by the youngest tectonothermal event. Four ancient mountain belts and six orogenies are preserved. Solid rocks outside the orogens have been assigned to different magmatic complexes or sedimentary successions based on their time of formation and tectonic affiliation. This approach allows relicts of older mountain-building activity to be preserved inside a younger orogen – for example, the effects of the Archean (2.8–2.6 Ga) orogeny inside the 2.0–1.8 Ga Svecokarelian orogen and Paleo–Mesoproterozoic (1.7–1.5 and 1.5–1.4 Ga) mountain-building processes inside the 1.1–0.9 Ga Sveconorwegian orogen. Sweden's five largest mineral districts are addressed in the context of this new lithotectonic framework, which forms the architecture to the contents of the chapters in this Memoir.
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HARTMANN, LÉO, LAURO NARDI, MILTON FORMOSO, MARCUS REMUS, EVANDRO DE LIMA i ANDRÉ MEXIAS. "Magmatism and Metallogeny in the Crustal Evolution of Rio Grande do Sul Shield, Brazil". Pesquisas em Geociências 26, nr 2 (31.12.1999): 45. http://dx.doi.org/10.22456/1807-9806.21123.

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The State of Rio Grande do Sul has a complex Precambrian/Cambrian shield, which has been investigated for four decades. This complexity involves ages ranging from 2.55 Ga (possibly 3.3 Ga) to 550 Ma (and even 470 Ma). The three major juvenile accretionary episodes occurred at 2.55 Ga, 2.26-2.02 Ga and 900-700 Ma, while a continental-scale crustal reworking (collisional) orogeny occurred from 780 to 550 Ma. The three accretionary orogenies are known as the Jequié, Transamazonian and Brasiliano Cycles, respectively. The Brasiliano Cycle includes the collisional orogeny. Magmatism was tholeiitic low-K bimodal basic-acid in the Archean (Santa Maria Chico granulites), and evolved to tonalitic-trondhjemitic-granodioritic in the Paleoproterozoic (Encantadas Complex). During the Paleoproterozoic/Archean transition, komatiites and basalts were formed in greenstone belts (Passo Feio Sul Formation). The end of the Transamazonian Cycle was the beginning of a long period of tectonic quiescence, and the region remained in the interior of the Atlantica Supercontinent until the beginning of the Brasiliano Cycle at ca. 900 Ma (Passinho Diorite). This Neoproterozoic cycle displays two classical orogenic types, namely the São Gabriel accretionary orogeny in the western part of the State and Dom Feliciano collisional orogeny in its eastern part. Accretion generated juvenile tonalite-trondhjemite-granodiorite associations with related ophiolites (Cerro Mantiqueiras Ophiolite), while the collision formed the voluminous and mostly peraluminous and high-K calcalkaline granites of the Dom Feliciano orogeny. The waning stages of the orogeny were responsible for the outpouring of a very expressive silica-saturated volcanism and eventually finished with the Rodeio Velho basalts at 470 Ma. Comparable Paleoproterozoic/Neoproterozoic Precambrian terranes surround the shield in Uruguay, in Santa Catarina and in western Africa. Comparable Neoproterozoic juvenile and reworked terranes occur in NE Africa. Widespread indications of metals are a good sign of possible deposits, but the two major types of deposits are the orogenic epizonal Bossoroca gold deposit and the distal magmatichydrothermal Lavras/Camaquã copper-gold deposits.
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Glen, R. A., S. Meffre i R. J. Scott. "Benambran Orogeny in the Eastern Lachlan Orogen, Australia". Australian Journal of Earth Sciences 54, nr 2-3 (marzec 2007): 385–415. http://dx.doi.org/10.1080/08120090601147019.

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Van Der Linden, Willem J. M. "Orogeny". Tectonophysics 111, nr 1-2 (styczeń 1985): 167–70. http://dx.doi.org/10.1016/0040-1951(85)90078-2.

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20

Burchfiel, B. C., i L. H. Royden. "Antler orogeny: A Mediterranean-type orogeny". Geology 19, nr 1 (1991): 66. http://dx.doi.org/10.1130/0091-7613(1991)019<0066:aoamto>2.3.co;2.

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21

Kelly, Sean, Christopher Beaumont i Jared P. Butler. "Inherited terrane properties explain enigmatic post-collisional Himalayan-Tibetan evolution". Geology 48, nr 1 (28.10.2019): 8–14. http://dx.doi.org/10.1130/g46701.1.

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Abstract Observations highlight the complex tectonic, magmatic, and geodynamic phases of the Cenozoic post-collisional evolution of the Himalayan-Tibetan orogen and show that these phases migrate erratically among terranes accreted to Asia prior to the Indian collision. This behavior contrasts sharply with the expected evolution of large, hot orogens formed by collision of lithospheres with laterally uniform properties. Motivated by this problem, we use two-dimensional numerical geodynamical model experiments to show that the enigmatic behavior of the Himalayan-Tibetan orogeny can result from crust-mantle decoupling, transport of crust relative to the mantle lithosphere, and diverse styles of lithospheric mantle delamination, which emerge self-consistently as phases in the evolution of the system. These model styles are explained by contrasting inherited mantle lithosphere properties of the Asian upper-plate accreted terranes. Deformation and lithospheric delamination preferentially localize in terranes with the most dense and weak mantle lithosphere, first in the Qiangtang and then in the Lhasa mantle lithospheres. The model results are shown to be consistent with 11 observed complexities in the evolution of the Himalayan-Tibetan orogen. The broad implication is that all large orogens containing previously accreted terranes are expected to have an idiosyncratic evolution determined by the properties of these terranes, and will be shown to deviate from predictions of uniform lithosphere models.
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22

Kranendonk, M. J. Van, i R. J. Wardle. "Crustal-scale flexural slip folding during late tectonic amplification of an orogenic boundary perturbation in the Paleoproterozoic Torngat Orogen, northeastern Canada". Canadian Journal of Earth Sciences 34, nr 12 (1.12.1997): 1545–65. http://dx.doi.org/10.1139/e17-126.

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Large variations in metamorphic grade over short distances, disparate orientations and diverse kinematics of contemporaneous structures, and a previously unexplained, 90° counterclockwise bend in the orogenic boundary of the amphibolite- to granulite-facies northern segment of the Paleoproterozoic Torngat Orogen are shown to be the result of multiple tectonic events acting upon an orogenic boundary perturbation. The perturbation was initiated when a promontory on the Nain Province margin, composed of a 1910–1885 Ma continental magmatic arc (Burwell domain), indented the Rae Province hinterland during the onset of collisional orogeny at ca. 1870 Ma (Dn+1). Sinistral transpression at ca. 1845–1822 Ma (Dn+2) caused formation of the orogen-parallel Abloviak shear zone and oblique burial of the Nain Province margin beneath a tilted section of the hot, buoyant magmatic arc. Reactivation of the orogen at ca. 1798–1770 Ma (Dn+3) involved crustal-scale flexural slip folding of the perturbation and simultaneous exhumation of the Burwell domain and the previously buried Nain crust across the Komaktorvik shear zone, which represents a sheared, tightened fold train localized along the western limit of thinned Nain crust affected by preorogenic rifting, but which does not represent a fundamental plate boundary. The along-strike heterogeneities in the Torngat Orogen document the influence of geometrical and competency heterogeneities in the colliding margins on subsequent deformation and the fact that heterogeneities in the deep crust persist through high-grade metamorphism.
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Bergström, Ulf, Michael B. Stephens i Carl-Henric Wahlgren. "Chapter 16 Polyphase (1.6–1.5 and 1.1–1.0 Ga) deformation and metamorphism of Proterozoic (1.7–1.1 Ga) continental crust, Idefjorden terrane, Sveconorwegian orogen". Geological Society, London, Memoirs 50, nr 1 (2020): 397–434. http://dx.doi.org/10.1144/m50-2018-34.

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AbstractCrust generated during an accretionary orogeny at 1.66–1.52 Ga (Gothian), and later during crustal extension at c. 1.51–1.49, c. 1.46, c. 1.34–1.30 Ga and after c. 1.33 Ga, dominate the Idefjorden terrane. Metamorphism under greenschist to, locally, high-pressure granulite facies, emplacement of syn-orogenic pegmatite and granite, and polyphase deformation followed at 1.05–1.02 Ga (Agder tectonothermal phase, Sveconorwegian orogeny). Sinistral transpressive deformation, including foreland-directed thrusting, preceded top-to-the-west movement and large-scale open folding along north–south axial trends during the younger orogeny. Crustal extension with emplacement of dolerite and lamprophyre dykes, norite–anorthosite, and a batholithic granite took place at c. 0.95–0.92 Ga (Dalane phase, Sveconorwegian orogeny). Ductile shear zones divide the Idefjorden terrane into segments distinguished by the character of the Gothian crustal component. Orthogneisses with c. 1.66 and c. 1.63–1.59 Ga protoliths occur in the Median segment; c. 1.59–1.52 Ga gneissic intrusive rocks and 1.6 Ga paragneisses with relicts of Gothian deformation and migmatization at c. 1.59 Ga and at c. 1.56–1.55 Ga occur in the Western segment. Mineral resources include stratabound Cu–Fe sulphides hosted by sandstone deposited after c. 1.33 Ga, and polymetallic quartz vein mineralization locally containing Au.
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Han, Yigui, Guochun Zhao, Peter A. Cawood, Min Sun, Qian Liu i Jinlong Yao. "Plume-modified collision orogeny: The Tarim–western Tianshan example in Central Asia". Geology 47, nr 10 (30.08.2019): 1001–5. http://dx.doi.org/10.1130/g46855.1.

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Abstract Plume-modified orogeny involves the interaction between a mantle plume and subducting oceanic lithosphere at accretionary margins. We propose that a plume can also be involved in collisional orogeny and accounts for the late Paleozoic geological relations in Central Asia. Continental collision between the Tarim and Central Tianshan–Yili blocks at the end Carboniferous resulted in an orogeny lacking continental-type (ultra)high-pressure [(U)HP] rocks and significant syncollision surface erosion and uplift, features normally characteristic of continent-continent interactions. Their absence from the Tianshan region corresponded with the arrival of a mantle plume beneath the northern Tarim. Elemental and isotopic data reveal an increasing influence of the mantle plume on magmatic petrogenesis from ca. 300 to 280 Ma, immediately after collision at 310–300 Ma. The rising mantle plume interrupted the normal succession of collisional orogenic events, destroying the deeply subducted continental crust and hence preventing slab break-off–induced continental rebound. Plume-modified continental collision thus limited continental (U)HP rock exhumation and associated surface uplift.
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Van Baelen, Hervé, i Manuel Sintubin. "Kinematic consequences of an angular unconformity in simple shear: an example from the southern border of the Lower Palaeozoic Rocroi inlier (Naux, France)". Bulletin de la Société Géologique de France 179, nr 1 (1.01.2008): 73–87. http://dx.doi.org/10.2113/gssgfbull.179.1.73.

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AbstractThe presence of an angular unconformity in combination with complex structures in the basement, lacking in the cover, is commonly seen as an indication for an orogenic event pre-dating the unconformity. The recognition of such an older orogenic event becomes, however, less evident in areas where both cover and basement were deformed together during an orogen post-dating the angular unconformity.The validity of this common interpretation has been evaluated at the southern border of the Lower Palaeozoic Rocroi basement inlier (Naux, northern France), where the basement-cover interface is very well exposed. This basement-cover interface, showing an angular unconformity, has classically been interpreted as evidence for an early Palaeozoic tectonometamorphic event, called the Ardennian orogeny, though only one penetrative cleavage, co-genetic with the structures present in both cover and basement, can be observed.A detailed geometrical study shows, however, that the presence of a tilted basement, involving the angular unconformity, provokes a rheological heterogeneity that causes a contrasting response of basement and cover with respect to the Variscan shortening. While Variscan progressive deformation gave rise to a rather regular cleavage refraction pattern in the subhorizontal multilayer cover sequence, a complex deformation, expressed by non-cylindrical folds, boudinage and shearing developed in the basement. The basement-cover interface itself played no rheological role, but has been passively sheared and folded as a consequence of the deformation of the basement. This study proves that the deformed basement-cover interface, allowing to link deformation in basement and cover, is a necessary tool to properly interpret complex deformation in the basement. With respect to the regional geodynamic evolution of the northern parts of the Central European Variscides, our kinematic model indeed demonstrates that this classical outcrop area bears no evidence for an early Palaeozoic orogenic event, and that the angular unconformity reflects the late Silurian – early Devonian onset of the Ardenne-Eifel basin development, rather than a middle Ordovician Ardennian orogeny.
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Pollock, Jeffrey C., James P. Hibbard i Cees R. van Staal. "A paleogeographical review of the peri-Gondwanan realm of the Appalachian orogen1This article is one of a series of papers published in this CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology." Canadian Journal of Earth Sciences 49, nr 1 (styczeń 2012): 259–88. http://dx.doi.org/10.1139/e11-049.

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The eastern edge of the Appalachian orogen is composed of a collection of Neoproterozoic – early Paleozoic domains, Avalonia, Carolinia, Ganderia, Meguma, and Suwannee, which are exotic to North America. Differences in the geological histories of these peri-Gondwanan domains indicate that each separated independently from Gondwana, opening the Rheic Ocean in their wake. Cambrian departure of Ganderia and Carolina was followed by the Ordovician separation of Avalonia and Silurian separation of Meguma. After separation in the early Paleozoic, these domains constituted the borderline between the expanding Rheic Ocean and contracting Iapetus Ocean. They were transferred to Laurentia by early Silurian closure of Iapetus and Devonian–Carboniferous closure of the Rheic Ocean during the assembly of Gondwana and Laurentia into Pangaea. The first domain to arrive at Laurentia was Carolinia, which accreted in the Middle Ordovician during the Cherokee orogeny. Salinic accretion of Ganderia occurred shortly thereafter and was followed by the Acadian accretion of Avalonia. The Acadian orogeny was immediately followed by Middle Devonian – Early Carboniferous accretion of Meguma and possibly Suwannee which led to the Fammenian orogeny. The episodicity of orogeny suggests that the present location of these domains parallels their order of accretion. However, each of these crustal blocks was translated along strike by large-scale Late Devonian – Carboniferous dextral strike–slip motion. The breakup of Pangaea occurred outboard of the Paleozoic collision zones that accreted Carolinia, Ganderia, Avalonia, Meguma, and Suwannee to Laurentia, leaving these terranes appended to North America during the Mesozoic opening of the Atlantic.
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Gautier, Pierre, Valérie Bosse, Zlatka Cherneva, Amélie Didier, Ianko Gerdjikov i Massimo Tiepolo. "Polycyclic alpine orogeny in the Rhodope metamorphic complex: the record in migmatites from the Nestos shear zone (N. Greece)". Bulletin de la Société géologique de France 188, nr 6 (2017): 36. http://dx.doi.org/10.1051/bsgf/2017195.

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The Rhodope Metamorphic Complex (RMC) is a high-grade crystalline massif located at the northern margin of the Aegean region. Numerous scenarios have been proposed for the evolution of the RMC during Alpine times. A debated issue is whether there has been a single protracted orogenic cycle since around the mid-Mesozoic or whether Alpine orogeny involved distinct episodes of subduction and crustal accretion. We describe a key outcrop located on the Nestos Shear Zone (NSZ), a major NNE-dipping top-to-SW shear zone characterized by an inverted metamorphic sequence. Structural and petrological data document the existence of two anatectic events. The first event, best preserved in decametric structural lenses, is pre-kinematic with respect to top-to-SW shearing and involved high-temperature “dry” melting. Zircon and monazite LA-ICPMS U-Th-Pb data indicate that this event occurred at ∼140 Ma. The second event is syn-kinematic with respect to top-to-SW shearing and involved lower-temperature water-assisted melting. Zircon and rutile LA-ICPMS U-Pb data indicate that this second event occurred at ∼40 Ma. During ongoing top-to-SW shearing and as late as ∼36 Ma, the rocks from the outcrop were at higher temperatures than the peak temperatures experienced by lower levels of the NSZ. This confirms the existence of the inverted metamorphic sequence and demonstrates that the NSZ was a major thrust at 36–40 Ma. The ∼100 Myr time laps between the two anatectic events encompasses the period from ∼115 to ∼70 Ma characterized by a gap in the geochronological record on the scale of the RMC (the Eastern Rhodope excluded). This ∼45 Myr gap likely reflects a period of tectonic quiescence between the mid-Mesozoic orogen and the Cenozoic one, attesting for polycyclic Alpine orogeny in the RMC. Unlike assumed in several geodynamic scenarios, the Alpine evolution of the RMC did not consist of a single orogenic cycle of Mesozoic age followed by Cenozoic crustal-scale extension triggered by mantle delamination. Polycyclic orogeny has resulted in a two-loop P-T-t path for the hangingwall unit of the NSZ. The Cenozoic P-T paths of this unit and the footwall unit merged while both units were being exhumed, a feature attributed to syn-thrusting extensional spreading of the main mass of the hangingwall unit above the NSZ.
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Maruyama, Shigenori. "Pacific-type orogeny revisited: Miyashiro-type orogeny proposed". Island Arc 6, nr 1 (marzec 1997): 91–120. http://dx.doi.org/10.1111/j.1440-1738.1997.tb00042.x.

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Argyriadis, Ion. "The superposed orogenesis of the alpine-mediterranean edifice". Boletín Geológico y Minero 127, nr 2-3 (30.09.2016): 593–612. http://dx.doi.org/10.21701/bolgeomin.127.2-3.020.

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The circum-Mediterranean chains must be considered as the result of two distinct orogenies. The apparent unity of the present structure is of formal order, due to the latest deformations. Since the Hercynian time there have been two periods of paroxysmal deformation; the younger fits the definition of the alpine orogeny; the older occurred during the Cretaceous and may correspond to the first great convergent relative drift of the Eurasiatic and African blocks. The Cretaceous or Mesogean orogeny is independent from the Alpine orogeny stricto sensu (Oligo-Miocene) and cannot be considered as its prefiguration. Being independent in time, it is independent in space as well. Even if this Mesogean orogeny can appear locally restricted to the ‘’internal’’ parts of the Alpine chains (Central Mediterranean area, Carpathes, Dinarides) this cannot be taken as a rule: towards the west, the Cretaceous deformations cross the axis of the western Alps and extend (new investigations) over Provence to the Betic chains and the Pyrenean area. Towards the east, the deformations of this period cross the Hellenides (new observations) and spread over the ‘’external’’ area in a spectacular way, interesting areas which have never been tectonised again (Cyprus, south-eastern Anatolia, northern Syria, Oman). As a whole, this large Cretaceous orogenic zone is part of a wider domain which extends over central Iran towards the Himalayas and eastern Asia, and has its equivalent on the western side of the Atlantic Ocean, in the Caribbean islands, Mexico and the Americas.
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Guo, Qi, Xiaohong Mao, Jianxin Zhang i Yawei Wu. "Paleozoic Tectonothermal Evolution in the West Qinling Orogen, Central China: Petrological and Chronological Evidence from Garnet Amphibolites". Minerals 13, nr 9 (8.09.2023): 1183. http://dx.doi.org/10.3390/min13091183.

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The Qinling Complex is located in the core of the northern Qinling Orogen and plays a key role in understanding the tectonic evolution of the Qinling Orogen, but its metamorphic evolution remains controversial. The combined investigation of petrographic observation, zircon U-Pb dating, and phase equilibria modeling for garnet amphibolites from the Tianshui area in the West Qinling Orogen is reported in this study. The results show that the garnet amphibolites record a clockwise P-T path characterized by a pre-TMax decompression heating stage, a temperature peak at P-T conditions of 0.84–0.99 GPa and 869–886 °C, followed by a decompression cooling stage. Zircon U-Pb dating yields four age populations of ~479 ± 4 Ma, ~451 ± 8 Ma, ~411 ± 4 Ma, and ~377 ± 6 Ma. The 479–450 Ma reflects the timing of the pre-TMax high–medium pressure upper amphibolite-facies metamorphism. The metamorphism at peak temperature condition occurred at c.411 Ma and was followed by decompression cooling to c.377 Ma. The Ordovician high–medium pressure metamorphism is related to the continental collision, which is slightly later than the HP–UHP eclogite-facies metamorphism in the East Qinling Orogen. The HT granulite-facies metamorphism at peak temperature condition took place at reduced pressures, suggesting thinning of the collision-thickened orogenic crust. Therefore, the northern West Qinling Orogen experienced a tectonothermal evolution from initial crust thickening to thinning during the Paleozoic collisional orogeny.
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Friedrich, Anke M., i Kip V. Hodges. "Geological significance of 40Ar/39Ar mica dates across a mid-crustal continental plate margin, Connemara (Grampian orogeny, Irish Caledonides), and implications for the evolution of lithospheric collisions". Canadian Journal of Earth Sciences 53, nr 11 (listopad 2016): 1258–78. http://dx.doi.org/10.1139/cjes-2016-0001.

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The Connemara region is a world-class example of a regional-scale, high-temperature metamorphic terrain. Its rock record documents formation of a bi-vergent orogenic wedge and associated calkalkaline magmatism in a an arc–continent collisional setting (Grampian orogeny), for which a protracted evolution was inferred based on a >75 Ma spread in U–Pb, Rb–Sr, and K–Ar mineral ages. In contrast, geological field observations imply a simple relationship between syntectonic magmatism, bi-vergent deformation, and Barrovian-type metamorphism. We explore the significance of the spread in apparent cooling ages using 40Ar/39Ar mica thermochronometers of varying grain sizes and composition, collected across metamorphic grades ranging from staurolite to upper sillimanite. We integrated geological and previously published geochronological evidence to identify a 32 Ma range (ca. 475–443 Ma) of permissible cooling ages and distinguished them from those dates not related to cooling after high-temperature metamorphism. Variations in 40Ar/39Ar dates at a single locality are ≤10 Ma, implying rapid cooling (≥6–26 °C/Ma) following metamorphism and deformation. A distinct cooling age variation (≥15 Ma) occurs on the regional scale, consistent with spatial differences in the metamorphic, magmatic, and deformational evolution across Connemara. This cooling record relates to a lateral thermal gradient (30 °C/km) in an evolving arc–continent collision, rather than to differential unroofing of the orogen. Our results imply that the large (≥50 Ma) spread in thermochronometers commonly observed in orogens does not automatically translate into a protracted cooling history, but that only a small number of thermochronometers supply permissible cooling ages.
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VACEK, FRANTIŠEK, i JIŘÍ ŽÁK. "A lifetime of the Variscan orogenic plateau from uplift to collapse as recorded by the Prague Basin, Bohemian Massif". Geological Magazine 156, nr 3 (10.11.2017): 485–509. http://dx.doi.org/10.1017/s0016756817000875.

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AbstractThe Ordovician to Middle Devonian Prague Basin, Bohemian Massif, represents the shallowest crust of the Variscan orogen corresponding toc.1–4 km palaeodepth. The basin was inverted and multiply deformed during the Late Devonian to early Carboniferous Variscan orogeny, and its structural inventory provides an intriguing record of complex geodynamic processes that led to growth and collapse of a Tibetan-type orogenic plateau. The northeastern part of the Prague Basin is a simple syncline cross-cut by reverse/thrust faults and represents a doubly vergent compressional fan accommodatingc.10–19 % ~NW–SE shortening, only minor syncline axis-parallel extension and significant crustal thickening. The compressional structures were locally overprinted by vertical shortening, kinematically compatible with ductile normal shear zones that exhumed deep crust in the orogen's interior atc. 346–337 Ma. On a larger scale, the deformation history of the Prague Syncline is consistent with building significant palaeoelevation during Variscan plate convergence. Based on a synthesis of finite deformation parameters observed across the upper crust in the centre of the Bohemian Massif, we argue for a differentiated within-plateau palaeotopography consisting of domains of local thickening alternating with topographic depressions over lateral extrusion zones. The plateau growth, involving such complex three-dimensional internal deformations, was terminated by its collapse driven by multiple interlinked processes including gravity, voluminous magma emplacement and thermal softening in the hinterland, and far-field plate-boundary forces resulting from the relative dextral motion of Gondwana and Laurussia.
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Mężyk, Miłosz, Michał Malinowski i Stanisław Mazur. "Imaging the East European Craton margin in northern Poland using extended correlation processing of regional seismic reflection profiles". Solid Earth 10, nr 3 (21.05.2019): 683–96. http://dx.doi.org/10.5194/se-10-683-2019.

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Abstract. In NE Poland, Eastern European Craton (EEC) crust of Fennoscandian affinity is concealed under a Phanerozoic platform cover and penetrated by sparse, deep research wells. Most of the inferences regarding its structure rely on geophysical data. Until recently, this area was covered only by the wide-angle reflection and refraction (WARR) profiles, which show a relatively simple crustal structure with a typical three-layer cratonic crust. ION Geophysical PolandSPAN™ regional seismic programme data, acquired over the marginal part of the EEC in Poland, offered a unique opportunity to derive a detailed image of the deeper crust. Here, we apply extended correlation processing to a subset (∼950 km) of the PolandSPAN™ dataset located in NE Poland, which enabled us to extend the nominal record length of the acquired data from 12 to 22 s (∼60 km of depth). Our new processing revealed reflectivity patterns, which we primarily associate with the Paleoproterozoic crust formed during the Svekofennian (Svekobaltic) orogeny, that are similar to those observed along the BABEL and FIRE profiles in the Baltic Sea and Finland, respectively. We propose a mid- to lower-crustal, orogeny-normal lateral flow model to explain the occurrence of two sets of structures that can be collectively interpreted as kilometre-scale S–C′ shear zones. The structures define a penetrative deformation fabric invoking ductile extension of hot orogenic crust in a convergent setting. Localized reactivation of these structures provided conduits for subsequent emplacement of gabbroic magma that produced a Mesoproterozoic anorthosite–mangerite–charnockite–granite (AMCG) suite in NE Poland. Delamination of thickened orogenic lithosphere may have accounted for magmatic underplating and fractionation into the AMCG plutons. We also found sub-Moho dipping mantle reflectivity, which we tentatively explain as a signature of the crustal accretion during the Svekofennian orogeny. Later tectonic phases (e.g. Ediacaran rifting, Caledonian orogeny) did not leave a clear signature in the deeper crust; however, some of the subhorizontal reflectors below the basement, observed in the vicinity of the AMCG Mazury complex, can be alternatively linked with lower Carboniferous magmatism.
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Dewey, John F., i Paul D. Ryan. "Connemara: its position and role in the Grampian Orogeny". Canadian Journal of Earth Sciences 53, nr 11 (listopad 2016): 1246–57. http://dx.doi.org/10.1139/cjes-2015-0125.

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In the Irish and British Caledonides, the early Ordovician Grampian Orogeny was the result of collision between the Laurentian rifted margin and an oceanic island arc. The Connemara terrain in western Ireland differs in position and character from all other parts of the exposed Dalradian rocks of the Grampian Orogen in lying south of the collided arc and fore-arc, and in having north-verging fold nappes that developed synchronously with the intrusion of huge volumes of calc-alkaline magmas that provided the heat for regional Barrovian metamorphism. We have tested this hypothesis with a numerical model, which demonstrates its admissablity. Connemara is not a terrane, displaced with respect to the remainder of the Grampian Orogen but was overridden, northwards, by the arc and its fore-arc basin (South Mayo Trough), frontal ophiolite complex (Deer Park) and accretionary complex (Killadangan). Deposition in the South Mayo Trough occurred below sea level and above the evolving Grampian Orogen, which developed on a hyper-extended rifted margin bounded to the north by the Clew Bay Line.
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Hildebrand, Robert S., i Joseph B. Whalen. "The mid-Cretaceous Peninsular Ranges orogeny: a new slant on Cordilleran tectonics? II: northern United States and Canada". Canadian Journal of Earth Sciences 58, nr 8 (sierpień 2021): 697–719. http://dx.doi.org/10.1139/cjes-2021-0006.

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The mid-Cretaceous Peninsular Ranges orogeny occurred in the North American Cordillera and affected rocks from Mexico to Alaska. It formed when a marine trough, open for ∼35 million years, closed by westerly subduction beneath a 140–100 Ma arc complex. In Part I, we described the features of the orogen in Mexico and California, west to east: back-arc trough, magmatic arc, 140–100 Ma seaway, post-collisional 99–84 Ma granodioritic–tonalitic plutons emplaced into the orogenic hinterland during exhumation, an east-vergent thrust belt, and farther east, a flexural foredeep. In western Nevada, where the Luning–Fencemaker thrust might be a mid-Cretaceous feature, arc and post-collisional plutons occur in proximity. The orogen continues through the Helena salient and Washington Cascades. In British Columbia, rocks of the 130–100 Ma Gambier arc lie west of the exhumed orogenic hinterland and 99–84 Ma post-collisional plutons to collectively indicate westerly subduction. East-dipping reverse faults near Harrison Lake, active from ∼100 Ma until ∼90 Ma, shed 99–84 Ma debris westward into the Nanaimo back-arc region. Within Insular Alaska, the Early Cretaceous Gravina basinal arc assemblage was deformed at 100 Ma and flanked to the east by a high-grade hinterland cut by post-collisional plutons. In mainland Alaska, the 100 Ma collision of Wrangellia and the Yukon–Tanana–Farewell composite terrane occurred above a southward-dipping subduction zone as shown by the 130–100 Ma Chisana arc sitting on Wrangellia and southward-dipping, northerly vergent thrusts in the Lower Cretaceous Kahiltna basin to the north. The outboard back-arc region was filled with post-collisional detritus of the McHugh complex.
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MA, XUXUAN, LIANGSHU SHU, JOSEPH G. MEERT i ZHIQIN XU. "The fingerprint of Precambrian basement in the Chinese Central Tianshan: evidence from inherited/xenocrystic zircons of magmatic rocks". Geological Magazine 152, nr 1 (22.08.2014): 176–83. http://dx.doi.org/10.1017/s0016756814000314.

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AbstractThe Central Asian Orogenic Belt is an accretionary orogen with many distinct terranes including the Chinese Central Tianshan, whose Precambrian tectonic affinity is not yet clearly known. We present Precambrian age spectra of inherited/xenocrystic zircons from magmatic rocks in the Chinese Central Tianshan, collected from published papers. The age patterns are dominated by zircons with ages ranging from 3261 to 541 Ma. These spectra provide robust clues regarding the Precambrian affinity of the Chinese Central Tianshan. The age spectra record two major tectonothermal events, represented by salient age peaks of c. 950 and 900 Ma within the ‘Grenville Orogeny’ period, and age peaks at c. 750 and 630 Ma, synchronous with magmatic events corresponding to Rodinia break-up. These results are consistent with the hypothesis that the Chinese Central Tianshan was part of the Tarim craton during Precambrian time as well as documenting its incorporation into, and separation from the Rodinia landmass.
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37

Wyman, Derek, i Robert Kerrich. "Mantle plume – volcanic arc interaction: consequences for magmatism, metallogeny, and cratonization in the Abitibi and Wawa subprovinces, CanadaThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, nr 5 (maj 2010): 565–89. http://dx.doi.org/10.1139/e09-049.

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The Abitibi and Wawa subprovinces of the southern Superior Province differ in terms of the extent of pre-existing 2750 Ma sialic crust and relationships between mantle plume type (tholeiitic basalt – komatiite) and arc type (tholeiite to calc-alkaline basalt – andesite – dacite – rhyolite) volcanic successions but evolved in close proximity to each other. Isotopic data, evidence from the Kapuskasing uplift, continuation of major structures associated with large gold deposits from the Abitibi into the Wawa subprovince and the related occurrence of diamonds in lamprophyric rocks in both subprovinces point to a common evolution prior to and during orogeny. Differences preserved in supracrustal sequences of the two subprovinces suggest that the main petrogenetic controls on orogenic gold deposits and lamprophyre-hosted diamond deposits lay in the lower crust and upper mantle. Similar processes must also have been active where gold and diamonds are associated on other Archean cratons, such as the Slave and possibly the Kaapvaal craton. Based on evidence preserved in the Abitibi–Wawa orogen, rapid crustal growth at ∼2.7 Ga was linked to the interplay between plate tectonics and mantle plumes. Key indicators in the model developed for the Abitibi–Wawa arc are the co-existence of plume-related rock types, modern-style adakites, major gold deposits, and lamprophyre-hosted diamond occurrences, at least in cases where shoshonitic host magmas can ascend rapidly through the crust. All of these indicators are now identified on the Kaapvaal craton by 3.1 Ga and many recur together in Paleoproterzoic and younger terranes, suggesting a common mechanism for rapid crustal growth through much of Earth’s history. The variety of granitoid types found within the Abitibi–Wawa orogen demonstrates that local tectonic factors, rather than a hotter average upper mantle, were important in controlling the type of magmas formed. Based on the geodynamic history of the subprovince, mantle plume interaction with an existing volcanic arc and the subduction of oceanic plateau crust played an important role in the formation of magmas similar to Cenozoic adakites. Flat subduction beneath a mantle wedge was probably responsible for the generation of the adakites and also promoted diamond stability at shallow depths while enhancing the reservoirs for subsequent orogenic gold deposits. The history of magmatism and mineralization in the Abitibi and Wawa subprovinces precludes an early or gradual development of a cratonic keel, which instead must have coupled with crust during the latest stages of orogeny.
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38

Searle, Michael P. "Tectonic evolution of the Caledonian orogeny in Scotland: a review based on the timing of magmatism, metamorphism and deformation". Geological Magazine 159, nr 1 (15.10.2021): 124–52. http://dx.doi.org/10.1017/s0016756821000947.

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AbstractClassic tectonic models for the Caledonian orogeny in Scotland involve Ordovician collision of Laurentia–Midland Valley arc (Grampian orogeny), followed by middle Silurian collision of Laurentia–Baltica (Scandian orogeny) and 500–700 km of sinistral displacement along the Great Glen fault separating the Northern Highlands (Moine Supergroup) from the Grampian Highlands (Dalradian Supergroup). A review of the timing of magmatic and metamorphic rocks across Scotland allows a simpler explanation that fits with a classic Himalayan-style continent–island arc–continent collision. Late Cambrian – Early Ordovician NW-directed ophiolite obduction (Highland Border complex) coincided with the ending of stable continental shelf sedimentation along the eastern margin of Laurentia. Following collision between Laurentia and the Midland Valley arc–microcontinent in Early Ordovician time, crustal thickening and shortening led to almost continuous regional metamorphism from c. 470 to 420 Ma, rather than two discrete ‘orogenies’ (Grampian, Scandian). U–Pb monazite and garnet growth ages indicating prograde metamorphism, and S-type granites related to melting of crustal protoliths are coeval in the Grampian and Northern Highlands terranes. There is no evidence that the Great Glen fault was a terrane boundary, and strike-slip shearing post-dated emplacement of Silurian – Early Devonian granites. Late orogenic alkaline granites (c. 430–405 Ma) in both Moine and Dalradian terranes are not associated with subduction. They are instead closely related to regional alkaline appinite–lamprophyric magmatism resulting from simultaneous melting of lower crust and enriched lithospheric mantle. Caledonian deformation and metamorphism in northern Scotland, with continuous SE-directed subduction, show geometry and time scales that are comparable to the Cenozoic India–Kohistan arc–Asia collisional Himalayan orogeny.
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39

Baig, M. S., R. D. Lawrence i L. W. Snee. "Evidence for late Precambrian to early Cambrian orogeny in northwest Himalaya, Pakistan". Geological Magazine 125, nr 1 (styczeń 1988): 83–86. http://dx.doi.org/10.1017/s0016756800009390.

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AbstractAn angular unconformity below Cambrian rocks is present in the northwest Himalaya in the Hazara district, Pakistan. Low-grade metamorphism and folding with axial planar cleavage present in Precambrian rocks below the unconformity, but not in those above it, confirm orogenic deformation at this time. This is the first clear evidence for such a deformation episode and it may be referred to locally as the Hazaran orogeny. Anatectic peraluminous granites of the Himalaya are of only slightly younger age and may be related to this orogenic episode.
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40

Pastor-Galán, Daniel, Gabriel Gutiérrez-Alonso i Arlo B. Weil. "The enigmatic curvature of Central Iberia and its puzzling kinematics". Solid Earth 11, nr 4 (8.07.2020): 1247–73. http://dx.doi.org/10.5194/se-11-1247-2020.

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Abstract. The collision between Gondwana and Laurussia that formed the latest supercontinent, Pangea, occurred during Devonian to early Permian times and resulted in a large-scale orogeny that today transects Europe, northwest Africa, and eastern North America. This orogen is characterized by an “S” shaped corrugated geometry in Iberia. The northern curve of the corrugation is the well-known and studied Cantabrian (or Ibero–Armorican) Orocline and is convex to the east and towards the hinterland. Largely ignored for decades, the geometry and kinematics of the southern curvature, known as the Central Iberian curve, are still ambiguous and hotly debated. Despite the paucity of data, the enigmatic Central Iberian curvature has inspired a variety of kinematic models that attempt to explain its formation but with little consensus. This paper presents the advances and milestones in our understanding of the geometry and kinematics of the Central Iberian curve from the last decade with particular attention to structural and paleomagnetic studies. When combined, the currently available datasets suggest that the Central Iberian curve did not undergo regional differential vertical-axis rotations during or after the latest stages of the Variscan orogeny and did not form as the consequence of a single process. Instead, its core is likely a primary curve (i.e., inherited from previous physiographic features of the Iberian crust), whereas the curvature in areas outside the core is dominated by folding interference from the Variscan orogeny or more recent Cenozoic (Alpine) tectonic events.
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41

Rast, Nicholas. "The Cadomian orogeny". Journal of Structural Geology 13, nr 6 (styczeń 1991): 739–40. http://dx.doi.org/10.1016/0191-8141(91)90036-i.

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42

Bingen, Bernard, Giulio Viola, Charlotte Möller, Jacqueline Vander Auwera, Antonin Laurent i Keewook Yi. "The Sveconorwegian orogeny". Gondwana Research 90 (luty 2021): 273–313. http://dx.doi.org/10.1016/j.gr.2020.10.014.

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43

Pin, Christian. "The cadomian orogeny". Tectonophysics 217, nr 3-4 (styczeń 1993): 357–58. http://dx.doi.org/10.1016/0040-1951(93)90019-g.

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44

Hildebrand, R. S., P. F. Hoffman i S. A. Bowring. "The Calderian orogeny in Wopmay orogen (1.9 Ga), northwestern Canadian Shield". Geological Society of America Bulletin 122, nr 5-6 (30.12.2009): 794–814. http://dx.doi.org/10.1130/b26521.1.

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45

Cawood, Peter A., Rob Strachan, Kathryn Cutts, Peter D. Kinny, Martin Hand i Sergei Pisarevsky. "Neoproterozoic orogeny along the margin of Rodinia: Valhalla orogen, North Atlantic". Geology 38, nr 2 (luty 2010): 99–102. http://dx.doi.org/10.1130/g30450.1.

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46

Sadeghi, S., i A. Yassaghi. "Spatial evolution of Zagros collision zone in Kurdistan – NW Iran, constraints for Arabia–Eurasia oblique convergence". Solid Earth Discussions 7, nr 3 (22.09.2015): 2735–73. http://dx.doi.org/10.5194/sed-7-2735-2015.

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Abstract. Stratigraphy, detailed structural mapping and crustal scale cross section of the NW Zagros collision zone evolved during convergence of the Arabian and Eurasian plates were conducted to constrain the spatial evolution of the belt oblique convergence since Late Cretaceous. Zagros orogeny in NW Iran consists of the Sanandaj–Sirjan, Gaveh Rud and ophiolite zones as internal, and Bisotoun, Radiolarite and High Zagros zones as external parts. The Main Zagros Thrust is known as major structures of the Zagros suture zone. Two stages of deformation are recognized in the external parts of Zagros. In the early stage, presence of dextrally deformed domains beside the reversely deformed domains in the Radiolarite zone as well as dextral-reverse faults in both Bisotoun and Radiolarite zones demonstrates partitioning of the dextral transpression. In the late stage, southeastward propagation of the Zagros orogeny towards its foreland resulted in synchronous development of orogen-parallel strike-slip and pure thrust faults. It is proposed that the first stage related to the late Cretaceous oblique obduction, and the second stage is resulted from Cenozoic collision. Cenozoic orogen-parallel strike-slip component of Zagros oblique faulting is not confined to the Zagros suture zone (Main Recent) but also occurred in the more external part (Marekhil–Ravansar fault system). Thus, it is proposed that oblique convergence of Arabia–Eurasia plates occurred in Zagros collision zone since the Late Cretaceous.
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Raharimahefa, Tsilavo, Bruno Lafrance i Douglas K. Tinkham. "New structural, metamorphic, and U–Pb geochronological constraints on the Blezardian Orogeny and Yavapai Orogeny in the Southern Province, Sudbury, Canada". Canadian Journal of Earth Sciences 51, nr 8 (sierpień 2014): 750–74. http://dx.doi.org/10.1139/cjes-2014-0025.

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New structural and geochronological data are presented for two orogenic events, the Blezardian and Yavapai orogenies, which affected the Paleoproterozoic Southern Province near Sudbury, Ontario, Canada. The Southern Province comprises ca. 2452 Ma metavolcanic rocks and metasedimentary rocks of the Huronian Supergroup, which were deposited along the southern margin of the Archean Superior craton during its evolution from a rifted to passive continental margin. Emplacement of the ca. 2415 Ma Creighton pluton during rifting was followed by its deformation and the development of a penetrative gneissic fabric during the ca. 2415 − ca. 2219 Ma Blezardian Orogeny. New laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) U–Pb zircon ages of 2343 ± 17 and 2344 ± 47 Ma on two granitic dikes that cut this fabric provide a new minimum age of ca. 2.34 Ga for the Blezardian Orogeny. The Sudbury area was then impacted by a large extraterrestrial bolide at ca. 1.85 Ga and deformed during the Penokean Orogeny. The southern part of the Southern Province was later reworked by regional folding and north-directed thrusting during the younger 1.7 Ga Yavapai Orogeny. The 1744 ± 29 Ma Eden Lake Complex was emplaced and deformed during this event, which produced a strong foliation overprinting the complex. The foliation formed at pressures of 2.8–4 kbar (1 kbar = 100 MPa) and temperatures of 540–565 °C and was intruded by a weakly deformed 1704 ± 13 Ma old granitic dike, bracketing the Yavapai event between 1744 ± 29 and 1704 ± 13 Ma in the Sudbury segment of the Southern Province. Crustal thickening associated with the Yavapai event resulted, locally, in minor pressure increases before or during regional metamorphism as revealed by phase equilibria modeling in the Raft Lake area; this evolution may be recorded elsewhere in the Ontario segment of the Southern Province.
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Houseman, Gregory A., i Lykke Gemmer. "Intra-orogenic extension driven by gravitational instability: Carpathian-Pannonian orogeny". Geology 35, nr 12 (2007): 1135. http://dx.doi.org/10.1130/g23993a.1.

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49

Schulmann, Karel. "Mechanics of Variscan Orogeny: A modern view on orogenic research". Comptes Rendus Geoscience 341, nr 2-3 (luty 2009): 97–102. http://dx.doi.org/10.1016/j.crte.2009.01.003.

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Şengör, A. M. Celâl, i Joann Stock. "The Ayyubid Orogen: An Ophiolite Obduction-Driven Orogen in the Late Cretaceous of the Neo-Tethyan South Margin". Geoscience Canada 41, nr 2 (7.05.2014): 225. http://dx.doi.org/10.12789/geocanj.2014.41.042.

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A minimum 5000-km long obduction-driven orogeny of medial to late Cretaceous age is located between Cyrenaica in eastern Libya and Oman. It is herein called the Ayyubid Orogen after the Ayyubid Empire that covered much of its territory. The Ayyubid orogen is distinct from other Alpide orogens and has two main parts: a western, mainly germanotype belt and an eastern mainly alpinotype belt. The germanotype belt formed largely as a result of an aborted obduction, whereas the alpinotype part formed as a result of successful and large-scale obduction events that choked a nascent subduction zone. The mainly germanotype part coincides with Erich Krenkel's Syrian Arc (Syrischer Bogen) and the alpinotype part with Ricou's Peri-Arabian Ophiolitic Crescent (Croissant Ophiolitique péri-Arabe). These belts formed as a consequence of the interaction of one of the now-vanished Tethyan plates and Afro-Arabia. The Africa-Eurasia relative motion has influenced the orogen's evolution, but was not the main causative agent. Similar large and complex obduction-driven orogens similar to the Ayyubids may exist along the Ordovician Newfoundland/Scotland margin of the Caledonides and along the Ordovician European margin of the Uralides.SOMMAIREEntre la Cyrénaïque dans l'est de la Libye et Oman, se trouve un ceinture orogénique d’au moins 5 000 km de longueur créé par obduction au Crétacé moyen et tardif. Nous le nommons ici l’orogène ayyoubide d’après l'empire ayyoubide qui couvrait une grande partie de son territoire. L'orogène ayyoubide qui est distincte des autres orogènes alpides, comporte deux parties principales : une bande occidentale, principalement germanotype, et une bande orientale principalement alpinotype. La bande germanotype s’est formée en grande partie à la suite d'une obduction avortée, tandis que la partie alpinotype s’est formée par des épisodes d’obduction à grande échelle qui ont étranglé une zone de subduction naissante. La partie principalement germanotype coïncide avec l’arc syrien d’Erich Krenkel (Syrischer Bogen), alors que la partie alpinotype correspond au croissant ophiolitique péri-Arabe de Ricou (Croissant ophiolitique péri-Arabe). Ces bandes se sont formées par l'interaction de l'une des plaques de la Téthys, maintenant disparues, avec l’Afro-Arabie. Le mouvement relatif Afrique-Eurasie a influencé l'évolution de l'orogène, mais ça n’a pas été le principal facteur. Des orogènes grandes et complexes résultant de mécanismes d’obduction similaires à l’orogène Ayyoubide peuvent exister le long de la marge des Calédonides de l'Ordovicien de Terre-Neuve/Écosse et le long de la marge européenne des Uralides de l'Ordovicien.
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