Articles de revues : « Permian tectonic »

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Song, Dongfang, Wenjiao Xiao, Brian F. Windley et Chunming Han. « Provenance and tectonic setting of late Paleozoic sedimentary rocks from the Alxa Tectonic Belt (NW China) : Implications for accretionary tectonics of the southern Central Asian Orogenic Belt ». GSA Bulletin 133, n^o 1-2 (9 juin 2020) : 253–76. http://dx.doi.org/10.1130/b35652.1.

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Abstract The Central Asian Orogenic Belt has long been considered the largest Phanerozoic accretionary orogen in the world; it developed through the subduction and final closure of the Paleo–Asian Ocean. However, the architecture and duration of the accretionary orogenesis of the Central Asian Orogenic Belt are still controversial despite decades of investigation. In this study, we present field, compositional, and stratigraphically controlled detrital zircon geochronological data for late Paleozoic sedimentary rocks from the Alxa Tectonic Belt to constrain their provenance, tectonic setting, and the overall tectonic configuration of the southern Central Asian Orogenic Belt. A Devonian sample yields a unimodal age peak (ca. 424 Ma) and broad late Mesoproterozoic ages. A Carboniferous sample has Early Silurian (ca. 438 Ma) and Late Devonian (ca. 382 Ma) peaks along with Neoproterozoic to Archean ages. The Permian samples are dominated by Ordovician–Devonian and Carboniferous–Permian ages. They yield maximum depositional ages ranging from ca. 291 Ma to 248 Ma and contain abundant zircon ages that are close to their depositional ages. These data reveal Ordovician–Silurian and Carboniferous–Permian magmatic flare-ups separated by a Devonian magmatic lull in the southern Central Asian Orogenic Belt. The arc terranes in southern Mongolia, central Beishan, and northern Alxa provided major detritus for the late Paleozoic sediments. An abrupt shift of zircon εHf(t) values at ca. 400 Ma reveals significant late Paleozoic crustal growth and excludes southern Alxa as a source. Oceanic basins prevented detritus from southern Alxa from reaching northern Alxa during Permian–Early Triassic time. A geological and provenance comparison of Permian basins in the southern Central Asian Orogenic Belt reveals the existence of two separate forearcs ascribed to bipolar subduction of the Paleo–Asian Ocean. Combined with recent paleomagnetic data, this leads us to advocate for an archipelago-style accretionary process induced by subduction retreat for the late Paleozoic tectonic evolution of the southern Central Asian Orogenic Belt, which continued into Late Permian–Early Triassic.

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Li, Yalong, Wei Yue, Xun Yu, Xiangtong Huang, Zongquan Yao, Jiaze Song, Xin Shan, Xinghe Yu et Shouye Yang. « Tectonic Evolution of the West Bogeda : Evidences from Zircon U-Pb Geochronology and Geochemistry Proxies, NW China ». Minerals 10, n^o 4 (10 avril 2020) : 341. http://dx.doi.org/10.3390/min10040341.

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The Bogeda Shan (Mountain) is in southern part of the Central Asian Orogenic Belt (CAOB) and well preserved Paleozoic stratigraphy, making it an ideal region to study the tectonic evolution of the CAOB. However, there is a long-standing debate on the tectonic setting and onset uplift of the Bogeda Shan. In this study, we report detrital zircon U-Pb geochronology and whole-rock geochemistry of the Permian sandstone samples, to decipher the provenance and tectonic evolution of the West Bogeda Shan. The Lower-Middle Permian sandstone is characterized by a dominant zircon peak age at 300–400 Ma, similar to the Carboniferous samples, suggesting their provenance inheritance and from North Tian Shan (NTS) and Yili-Central Tian Shan (YCTS). While the zircon record of the Upper Permian sandstone is characterized by two major age peaks at ca. 335 Ma and ca. 455 Ma, indicating the change of provenance after the Middle Permian and indicating the uplift of Bogeda Shan. The initial uplift of Bogeda Shan was also demonstrated by structural deformations and unconformity occurring at the end of Middle Permian. The bulk elemental geochemistry of sedimentary rocks in the West Bogeda Shan suggests the Lower-Middle Permian is mostly greywacke with mafic source dominance, and tectonic setting changed from the continental rift in the Early Permian to post rift in the Middle Permian. The Upper Permian mainly consists of litharenite and sublitharenite with mafic-intermediate provenances formed in continental island arcs. The combined evidences suggest the initial uplift of the Bogeda Shan occurred in the Late Permian, and three stages of mountain building include the continental rift, post-rift extensional depression, and continental arc from the Early, Middle, to Late Permian, respectively.

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Chen, Xingyu, Zhijie Zhang, Xuanjun Yuan, Li Wan, Chuanmin Zhou, Yinhe Liu et Dawei Cheng. « The Evolution of Permian Source-to-Sink Systems and Tectonics Implications in the NW Junggar Basin, China : Evidence from Detrital Zircon Geochronology ». Minerals 12, n^o 9 (15 septembre 2022) : 1169. http://dx.doi.org/10.3390/min12091169.

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The basin type of the Junggar Basin changed during the Permian, but the time constraint of the tectonic evolution remains unclear. Besides, the fan deltas developed in the Permian in the Mahu Sag in the northwestern of the oil-rich basin. However, the provenances of the sedimentary systems remain unclear. Based on petrology and detrital zircon U-Pb ages, this study investigates the source-to-sink systems evolution and tectonics implications. Abundant lithic clasts in sandstones with low compositional and textural maturity imply proximal sources. The dating results showed a dominant peak (310–330 Ma) and a secondary peak (400–440 Ma) in the northern Mahu Sag, only one peak at 295–325 Ma in the central Mahu Sag, several peaks at 270–350 Ma in the southern Mahu Sag, and multiple peaks at 370–450 Ma in the Zhongguai Uplift. Thus, the north-western Junggar Basin was divided into four major source-to-sink systems, with adjacent central West Junggar as the main provenance and northern and southern West Junggar as the secondary provenance. The proportion of sediment supply from the southern and northern West Junggar is higher during the Middle-Late Permian. It suggests that the source-to-sink systems show inheritance and evolve from a single provenance into a complex provenance, indicating the uplift of West Junggar. The tectonic inversion may occur early in the Middle Permian and the response to tectonic activity is stronger in the southern West Junggar than in the northern West Junggar.

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Wopfner, H., et C. Z. Kaaya. « Stratigraphy and morphotectonics of Karoo deposits of the northern Selous Basin, Tanzania ». Geological Magazine 128, n^o 4 (juillet 1991) : 319–34. http://dx.doi.org/10.1017/s0016756800017593.

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AbstractLate Permian Karoo deposits of the northern Selous Basin in south-central Tanzania comprise conglomerates and diamictitic boulder beds of alluvial and scarp-foot fan origin. These merge with grey to greenish sandstones, siltstones and black shales of deltaic and lacustrine environments. Microflora assemblages indicate a late Permian age. Lateral changes and interfingering of various lithofacies units are common. Depositional development was controlled by syndepositional faulting and variations of gradients resulting from fault movements. The position of the fault scarp separating the basin area from the elevated basement horst to the west roughly corresponded with the present boundary between the Selous Basin and the Precambrian metamorphics of the Uluguru Mountains.The late Permian Karoo succession of this part of the Selous Basin apparently overlaps older Karoo deposits contained in the north-northeast trending narrow graben structures. It is therefore regarded as a new depositional event which was initiated by renewed tensional tectonism in late Permian time. During this tectonic episode the narrow early Karoo graben structures were expanded into much broader rift basins. Material eroded from the rift shoulders and associated highlands was literally dumped across the fault scarps, forming debris aprons and scarp-foot fans. Rivers emanating from the highlands formed large alluvial fans and, further afield, deltas issued into freshwater lakes.Some of these late Permian faults were rejuvenated by late Cretaceous to early Tertiary tectonism. Thermal waters circulating along fractures converted feldspars, biotites and hornblendes to prehnite. Further tectonic adjustments in mid Tertiary time led to the present-day morphology.

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Guanglong, Shen, Wang Yong-dong, Jun Wang, Liu Huaqing et Zhang Shuangquan. « Tectonic implications of Permian floras in China ». Journal of Palaeosciences 45 (31 décembre 1996) : 324–28. http://dx.doi.org/10.54991/jop.1996.1251.

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On the basis of comprehensive palaeophytogeographical study, the Permian flora of China may be divided into 4 phytorealms, 5 phytoareas and 13 phytoprovinces. The tectonic implications of the Permian floras and phytoprovinces in China are preliminarily discussed.

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Han, Zuozhen, Jingjing Li, Zhigang Song, Guyao Liu, Wenjian Zhong, Lihua Gao et Qingxiang Du. « Geochemistry and Zircon U-Pb-Hf Isotopes of Metamorphic Rocks from the Kaiyuan and Hulan Tectonic Mélanges, NE China : Implications for the Tectonic Evolution of the Paleo-Asian and Mudanjiang Oceans ». Minerals 10, n^o 9 (22 septembre 2020) : 836. http://dx.doi.org/10.3390/min10090836.

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The Late Paleozoic–Early Mesozoic tectonic evolution of the Changchun-Yanji suture (CYS) was mainly associated with the Paleo-Asian and Mudanjiang tectonic regimes. However, the spatial and temporal overprinting and variations of these two regimes remains are still dispute. In order to evaluate this issue, in this contribution, we present new zircon U-Pb ages and a whole-rock geochemical and zircon Hf isotopic dataset on a suite of metamorphic rocks, including gneisses, actinolite schist, leptynites, and biotite schists, from tectonic mélanges in northern Liaoning and central Jilin provinces, NE China. Based on zircon LA-ICP-MS U-Pb dating results, protoliths show wide ranges of aging spectrum, including Paleoproterozoic (2441 Ma), Early Permian (281 Ma), Late Permian (254 Ma), and Late Triassic (230 Ma). The Permian protoliths of leptynites from the Hulan Tectonic Mélange (HLTM) and gneisses from the Kaiyuan Tectonic Mélange (KYTM) exhibit arc-related geochemical signatures, implying that the Paleo-Asian Ocean (PAO) did not close prior to the Late Permian. The Late Triassic protoliths of gneisses from the KYTM, in combination with previously reported coeval igneous rocks along the CYS, comprises a typical bimodal igneous suite in an E–W-trending belt, suggesting a post-orogenic extensional environment. Consequently, we infer that the final closure of the PAO took place during the Early–Middle Triassic. The Early Permian protoliths of biotite schists from the HLTM are alkali basaltic rocks and contain multiple older inherited zircons, which, in conjunction with the geochemical features of the rocks, indicate that they were generated in a continental rift related to the initial opening of the Mudanjiang Ocean (MO). Data from this contribution and previous studies lead us to conclude that the MO probably opened during the Middle Triassic, due to the north–south trending compression caused by the final closure of the PAO.

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Maystrenko, Y., U. Bayer et M. Scheck-Wenderoth. « 3D reconstruction of salt movements within the deepest post-Permian structure of the Central European Basin System - the Glueckstadt Graben ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 85, n^o 3 (septembre 2006) : 181–96. http://dx.doi.org/10.1017/s0016774600021466.

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AbstractThe Glueckstadt Graben is a prominent structure of the Central European Basin System, where the sedimentary patterns are extensively affected by Permian salt movements. The relations of the sedimentary patterns to salt structures have been analyzed through present-day distributions of sediments. In addition, a three-dimensional backward modelling approach has been applied to determine the original salt distribution in response to the unloading due to sequential backstripping of the stratigraphic layers. The results of the modelling reveal the thickness distribution of the Permian salt for 5 time intervals from the end of the Triassic to present day. Spatial agreement has been found between the development of the depleted zone of the Permian salt through time and the observed distribution of the maximum subsidence for the different stratigraphic units above the salt. The sedimentation centres for each time interval are always located above the zone of reduced or depleted Permian salt. In the central part of the Glueckstadt Graben, the depletion occurred already in the Triassic and perfectly correlates with the thickest Triassic. During the Jurassic, Cretaceous and Tertiary, the areas of depleted Permian salt shifted towards the basin flanks, and the same occurred with the centres of maximum sediment deposition. Thus, the results of the modelling strongly support the conclusion that salt withdrawal has played a major role during the Meso-Cenozoic evolution of the Glueckstadt Graben and that the progressive depletion of the Permian salt layer, from the central part towards the margins, created the large part of the accommodation space for sedimentation in addition to tectonic subsidence.Furthermore, our study has several important implications for salt behaviour in different tectonic settings. In general, the results of modelling indicate a good correlation between the main phases of salt movements and tectonic events in the area under consideration. During the Triassic, the first stage of diapirism in the Glueckstadt Graben occurred within the central part of the basin. Regional extension may have triggered reactive diapirism and caused the formation of the deep primary rim synclines. Once the salt structures had reached the critical size, buoyancy forces supported their continued growth until the Jurassic when extension-induced regional stresses once more affected the Glueckstadt Graben. The results of the modelling indicate very little salt activity during the late Early Cretaceous-early Late Cretaceous when the area of the Glueckstadt Graben was tectonically silent. Therefore, our study supports the concept of tectonically induced salt movements which can be interrupted during the absence of tectonic forces. Salt movements were reactivated in the marginal troughs by compressional forces during the latest Late Cretaceous-Early Cenozoic. Paleogene-Neogene salt withdrawal led to the growth of N-S oriented salt structures mainly at the margins of the basin. This phase of salt tectonics correlates temporally with almost W-E extension. This indicates a renewed change in tectonic regime after Late Cretaceous-Early Cenozoic compression.

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Filippi, Marco, Maria Iole Spalla, Nicola Pigazzini, Valeria Diella, Jean-Marc Lardeaux et Davide Zanoni. « Cld-St-And-Bearing Assemblages in the Central Southalpine Basement : Markers of an Evolving Thermal Regime during Variscan Convergence ». Minerals 11, n^o 10 (13 octobre 2021) : 1124. http://dx.doi.org/10.3390/min11101124.

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Multiscale structural analysis is carried out to explore the sequence of superposed pre-Alpine chloritoid–staurolite–andalusite metamorphic assemblages in the polydeformed Variscan basement of the upper Val Camonica, in the central Southalpine domain. The dominant fabric in the upper Val Camonica basement is the late-Variscan S2 foliation, marked by greenschist facies minerals and truncated by the base of Permian siliciclastic sequences. The intersection with the sedimentary strata defines a Permian age limit on the pre-Alpine tectono–metamorphic evolution and exhumation of the Variscan basement. The detailed structural survey revealed that the older S1 foliation was locally preserved in low-strained domains. S1 is a composite fabric resulting from combining S1a and S1b: in the metapelites, S1a was supported by chloritoid, garnet, and biotite and developed before S1b, which was marked by staurolite, garnet, and biotite. S1a and S1b developed at intermediate pressure amphibolite facies conditions during the Variscan convergence, S1a at T = 520–550 °C and P ≃ 0.8 GPa, S1b at T = 550–650 °C and P = 0.4–0.7 GPa. The special feature of the upper Val Camonica metapelites is andalusite, which formed between the late D1b and early D2 tectonic events. Andalusite developed at T = 520–580 °C and P = 0.2–0.4 GPa in pre-Permian times, after the peak of the Variscan collision and before the exhumation of the Variscan basement and the subsequent deposition of the Permian covers. It follows that the upper Val Camonica andalusite has a different age and tectonic significance as compared to that of other pre-Alpine andalusite occurrences in the Alps, where andalusite mostly developed during exhumation of high-temperature basement rocks in Permian–Triassic times.

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Costamagna, Luca Giacomo. « The carbonates of the post-Variscan basins of Sardinia : the evolution from Carboniferous–Permian humid-persistent to Permian arid-ephemeral lakes in a morphotectonic framework ». Geological Magazine 156, n^o 11 (31 mai 2019) : 1892–914. http://dx.doi.org/10.1017/s0016756819000232.

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AbstractLate to post-Variscan sedimentary basins of Sardinia were influenced during Pennsylvanian to Permian times by two main tectono-sedimentary cycles: a Pennsylvanian to Cisuralian cycle represented mainly by dark limnic deposits, overlain by a Guadalupian to a possibly Lopingian cycle, mostly characterized by red-bed deposits. Lacustrine waterbodies developed in some sedimentary basins that were filled with siliciclastic to frequently early silicified carbonate deposits, depending on the climate and environmental conditions, landscape morphology and tectonic regime. The limnic successions of the lower tectono-sedimentary cycle were deposited in permanent, tens of metres deep lakes in deep, narrow tectonic strike-slip basins under a temperate to warm-humid climate. They started as lakes with terrigenous sedimentary input and developed minor carbonate deposits mainly at the end of their story. Conversely, the red-bed successions of the upper cycle were deposited in ephemeral, shallow playa lakes related to wider basins in an extensive alluvial plain under a hot and arid climate. Here, the siliciclastic sediments are intercalated with thin carbonate beds that are typical of a high evaporation rate. The evolution of the lake type could be related not only to a major climatic shift, but also to the changing morphotectonic conditions of the Variscan chain influencing the local microclimate. Comparisons with coeval successions in the Provence Basin, the Massif Central Aumance basin (France) and the Saar–Nahe Basin (Germany) show both similarities and differences between the basins.

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Metcalfe, I. « Permian tectonic framework and palaeogeography of SE Asia ». Journal of Asian Earth Sciences 20, n^o 6 (août 2002) : 551–66. http://dx.doi.org/10.1016/s1367-9120(02)00022-6.

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Uspensky, B. V., N. G. Nurgalieva, S. E. Valeeva et E. E. Andreeva. « Tectonic aspects of super-viscous oil deposits formation and placement within the Volga-Ural anteclise ». SOCAR Proceedings, SI2 (30 décembre 2021) : 54–58. http://dx.doi.org/10.5510/ogp2021si200559.

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The article discusses the tectonics and developmental features of the Volga-Ural anteclise during the Baikalian, Caledonian, Hercynian and Alpine tectogenesis cycles. In this paper, particular attention is paid to stages and directional development during the evolution of geological structures. The main factors of the formation and destruction of Permian viscous oil and natural bitumen reservoirs are presented in the provisions of oil ontogenesis. It was noted the cyclical nature of these phenomena. Keywords: Volga-Ural anteclise; super-viscous oil; tectonic; reservoir; oil.

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Sissingh, W. « Palaeozoic and Mesozoic igneous activity in the Netherlands : a tectonomagmatic review ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 83, n^o 2 (juin 2004) : 113–34. http://dx.doi.org/10.1017/s0016774600020084.

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AbstractTo date, igneous rocks, either intrusive or extrusive, have been encountered in the Palaeozoic-Mesozoic sedimentary series of the Netherlands in some 65 exploration and production wells. Following 17 new isotopic K/Ar age determinations of the recovered rock material (amounting to a total of 28 isotopic ages from 21 different wells), analysis of the stratigraphic distribution of the penetrated igneous rock bodies showed that the timing of their emplacement was importantly controlled by orogenic phases involving intra-plate wrench and rift tectonics. Magmatism coincided with the Acadian (Late Devonian), Sudetian (early Late Carboniferous), Saalian (Early Permian), Early Kimmerian (late Late Triassic), Mid-Kimmerian (Late Jurassic), Late Kimmerian (earliest Cretaceous) and Austrian (latest Early Cretaceous) tectonic phases. This synchroneity presumably reflects (broadly) coeval structural reorganizations of respectively the Baltica/Fennoscandinavia-Laurentia/Greenland, Laurussia-Gondwana, African-Eurasia and Greenland/Rockall-Eurasia plate assemblies. Through their concomitant changes of the intra-plate tectonic stress regime, inter-plate motions induced intra-plate tectonism and magmatism. These plate-tectonics related events determined the tectonomagmatic history of the Dutch realm by inducing the formation of localized centres, as well as isolated spot occurrences, of igneous activity. Some of these centres were active at (about) the same time. At a number of centres igneous activity re-occurred after a long period of time.

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Liu, Huichuan, Jichun Wang, Chun-Kit Lai, Yinglei Li, Jingfan Wang, Chongyu Song, Jiadong Zhang, Xin Zhao et Jiangdong Qin. « Anatomy of two Permian greenschist- to blueschist-facies tectonic mélanges in the Solonker Suture Zone (Inner Mongolia, northeastern China) : evidence for divergent double subduction and soft collision ». Journal of the Geological Society 177, n^o 5 (11 juin 2020) : 981–96. http://dx.doi.org/10.1144/jgs2020-006.

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The timing and processes of the Paleo-Asian Ocean (PAO) closure are still controversial issues due to ambiguous interpretation of the regional geological records. We describe the structural and kinematic features of two Permian greenschist-/blueschist-facies tectonic mélanges at Zhurihe and Erdaojing in Inner Mongolia (northeastern China), separated by the Solonker Suture. The tectonic mélanges have block-in-matrix fabrics. The Zhurihe tectonic mélange in the south is dominated by NE-trending folds, and east–west- to NE-trending reverse/strike-slip faults, indicating a NW–SE compressive direction. Blocks in the Zhurihe mélange include ophiolitic fragments (c. 292 Ma) and ocean island sequences (c. 274 Ma), which show E-MORB and OIB geochemical affinities, respectively. The matrix includes blueschist, greenschist, quartz schist and clastics, of which the blueschist yielded a zircon U–Pb age of c. 255 Ma, and is geochemically E-MORB-like. The Erdaojing mélange north of the Solonker Suture is dominated by east–west-trending folds, and NE- and NW-trending reverse faults, indicating a north–south compressive orientation. The Erdaojing mélange is composed of early Permian (c. 281 Ma) ophiolite blocks, and middle Permian (c. 266 Ma) actinolite schist and clastics as the matrix. The Erdaojing ophiolitic rocks are geochemically N-MORB tholeiitic. Our results define two parallel Permian MORB-type ophiolitic belts separated by the central Solonker Suture. These observations are evidence for the Permian divergent double subduction and Early Triassic soft-collision model for the PAO along the Solonker Suture.Supplementary material: Detailed analytical methods and results are available at: https://doi.org/10.6084/m9.figshare.c.5008910

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Jablonski, D., et A. J. Saitta. « PERMIAN TO LOWER CRETACEOUS PLATE TECTONICS AND ITS IMPACT ON THE TECTONO-STRATIGRAPHIC DEVELOPMENT OF THE WESTERN AUSTRALIAN MARGIN ». APPEA Journal 44, n^o 1 (2004) : 287. http://dx.doi.org/10.1071/aj03011.

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The post-Lower Permian succession of the Perth Basin and Westralian Superbasin can be directly related to the plate tectonic evolution of the Gondwanan Super-continent. In the Late Permian to Albian the northern edge of Gondwana continued to break into microplates that migrated to the north and were accreted into what is today the southeastern Asia (Burma–China) region. These separation events are recorded as a series of stratigraphically distinct transgressions (corresponding to the initial stretching of the asthenosphere and acceleration of subsidence rates) followed by rapid regressions (when new oceanic crust was emplaced in thinned continental crust causing uplifts of large continental masses). Because the events are synchronous across large regions, and may be identified from specific log and seismic signatures, the intensity of stratigraphically related transgressive/regressive cycles varies, depending on the distance from the break-up centres and these cycles allow the identification of regionally significant megasequences even in undrilled areas. The tectonic evolution and resulting stratigraphy can be described by eight plate tectonic events:Visean (Carboniferous) break-up of the southeastern Asia (Simao, Indochina and South China);Kungurian (uppermost Early Permian) break-up of Qiangtang and Sibumasu;Lowermost Norian uplift due to Bowen Orogeny in eastern Australia;Hettangian break-up of Mangkalihat (northeastern Borneo);Oxfordian break-up of Argo/West Burma, and Sikuleh (Western Sumatra);Kimmeridgian break-up of the West Sulawesi microplate;Tithonian break-up of Paternoster-Meratus (central Borneo); andValanginian break-up of Greater India/India.These events should be identifiable in all Australian Phanerozoic basins and beyond, potentially providing a template for a synchronisation of the Permian to Early Cretaceous stratigraphy.

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Vozárová, Anna, Sergey Presnyakov, Katarína Šarinová et Miloš Šmelko. « First evidence for Permian-Triassic boundary volcanism in the Northern Gemericum : geochemistry and U-Pb zircon geochronology ». Geologica Carpathica 66, n^o 5 (1 octobre 2015) : 375–91. http://dx.doi.org/10.1515/geoca-2015-0032.

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AbstractSeveral magmatic events based on U-Pb zircon geochronology were recognized in the Permian sedimentary succession of the Northern Gemeric Unit (NGU). The Kungurian magmatic event is dominant. The later magmatism stage was documented at the Permian-Triassic boundary. The detrital zircon assemblages from surrounding sediments documented the Sakmarian magmatic age. The post-orogenic extensional/transtensional faulting controlled the magma ascent and its emplacement. The magmatic products are represented by the calc-alkaline volcanic rocks, ranging from basaltic metaandesite to metarhyolite, associated with subordinate metabasalt. The whole group of the studied NGU Permian metavolcanics has values for the Nb/La ratio at (0.44–0.27) and for the Nb/U ratio at (9.55–4.18), which suggests that they represent mainly crustal melts. Magma derivation from continental crust or underplated crust is also indicated by high values of Y/Nb ratios, ranging from 1.63 to 4.01. The new206U–238Pb zircon ages (concordia age at 269 ± 7 Ma) confirm the dominant Kungurian volcanic event in the NGU Permian sedimentary basin. Simultaneously, the Permian-Triassic boundary volcanism at 251 ± 4 Ma has been found for the first time. The NGU Permian volcanic activity was related to a polyphase extensional tectonic regime. Based on the new and previous U-Pb zircon ages, the bulk of the NGU Permian magmatic activity occurred during the Sakmarian and Kungurian. It was linked to the post-orogenic transpression/transtension tectonic movements that reflected the consolidation of the Variscan orogenic belt. The Permian-Triassic boundary magmatism was accompanied by extension, connected with the beginning of the Alpine Wilson cycle.

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Elliott, L. G. « POST-CARBONIFEROUS TECTONIC EVOLUTION OF EASTERN AUSTRALIA ». APPEA Journal 33, n^o 1 (1993) : 215. http://dx.doi.org/10.1071/aj92017.

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Analysis of seismic data from the Bowen and Surat Basins has yielded valuable information on the Permian and Triassic evolution of eastern Australia. When combined with seismic data from the Clarence-Moreton and Maryborough Basins, a new understanding of the post-Triassic evolution of the region can be gained, with widespread implications for other eastern Australian basins.The Early Permian-Middle Triassic Bowen-Sydney Basin is a foreland basin system extending 2000 km in preserved section from Nowra in the south to Collinsville in the north. Permian outcrops as far north as Cape York were probably part of the same system prior to deformation and erosion. The basins in the Bowen-Sydney system were linked by similar structural and stratigraphic patterns controlled by a magmatic arc to the east. The Esk Trough and associated remnant basins east of the Taroom Trough were part of the Middle Triassic foreland sequence. The structural style in the system is dominated by thrusting from the east. An Early Triassic deformation is shown to be the most important, rather than the previously believed Middle Triassic event.The overlying Jurassic-Cretaceous foreland system, which included the Surat, Maryborough and Clarence-Moreton Basins, were once joined behind another magmatic arc, east of the Triassic arc position. A major mid-Cretaceous deformation is documented which fragmented the Jurassic-Cretaceous foreland basin into a number of remnant basins prior to the opening of the Tasman Sea in the Cenomanian. The dominant structural style is again thrusting from the east. Given the severity of the deformation, its effects are expected to be present in continental margin basins around Australia.

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Erlström, Mikael. « Chapter 24 Carboniferous–Neogene tectonic evolution of the Fennoscandian transition zone, southern Sweden ». Geological Society, London, Memoirs 50, n^o 1 (2020) : 603–20. http://dx.doi.org/10.1144/m50-2016-25.

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AbstractThe Fennoscandian transition zone, including the Sorgenfrei–Tornquist Zone, constitutes the weakened and faulted bedrock between a craton, including the ancient continent Baltica to the north, and the boundary between Baltica and Avalonia along the Trans-European Fault Zone to the south. Early Permian subsidence in this transition zone resulted in the development of various basins and the initiation of a more or less continuous Permian–Paleogene depositional cycle. In southwestern Sweden, magmatic activity associated with transtensional deformation along the Sorgenfrei–Tornquist Zone prevailed during the Late Carboniferous–Permian. However, the transition zone is dominated by a Mesozoic sedimentary rock succession displaying both hiatuses and great lateral variability in composition and thickness, which can be related to several tectonic events including the progressive break-up of Pangaea. Much of the deposition took place in continental, coastal and shallow-marine settings. Early–Middle Jurassic block faulting and basanitic or melanephelinitic volcanism, as well as Late Cretaceous tectonic inversion along the Sorgenfrei–Tornquist Zone, related to a changeover to a predominantly compressive tectonic regime coeval with the Alpine orogeny, significantly influenced the depositional setting. Subsequent Paleogene–Neogene regional uplift of the southwestern margin of Baltica resulted in significant erosion of the bedrock.

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Piqué, Alain. « About the tectonic setting of the Moroccan Permian Basins ». Comptes Rendus Geoscience 334, n^o 6 (janvier 2002) : 439–40. http://dx.doi.org/10.1016/s1631-0713(02)01778-9.

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Nestell, Merlynd K., et Charles D. Blome. « Some contrasting biostratigraphic links between the Baker and Olds Ferry Terranes, eastern Oregon ». Micropaleontology 61, n^o 4-5 (2015) : 389–417. http://dx.doi.org/10.47894/mpal.61.4.08.

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New stratigraphic and paleontologic data indicate that ophiolitic melange windows in the Olds Ferry terrane of eastern Oregon contain limestone blocks and chert that are somewhat different in age than those present in the adjacent Baker terrane melange. The melange windows in the Olds Ferry terrane occur as inliers in the flyschoid Early and Middle Jurassic age Weatherby Formation, which depositionally overlies the contact between the melange-rich Devonian to Upper Triassic rocks of the Baker terrane on the north, and Upper Triassic and Early Jurassic volcanic arc rocks of the Huntington Formation on the south. The Baker terrane and Huntington Formation represent fragments of a subduction complex and related volcanic island arc, whereas the Weatherby Formation consists of forearc basin sedimentary deposits. The tectonic blocks in the melange windows of the Weatherby Formation (in the Olds Ferry terrane) are dated by scarce biostratigraphic evidence as Upper Pennsylvanian to Lower Permian and Upper Triassic. In contrast, tectonic blocks of limestone in theBaker terrane yield mostly fusulinids and small foraminifers of Middle Pennsylvanian Moscovian age at one locality.Middle Permian (Guadalupian) Tethyan fusulinids and smaller foraminifers (neoschwagerinids and other Middle Permian genera) are present at a few other localities. Late Triassic conodonts and bryozoans are also present in a few of the Baker terrane tectonic blocks. These limestone blocks are generally embedded in Permian and Triassic radiolarian bearing chert or argillite. Based on conodont, radiolarian and fusulinid data, the age limits of the meange blocks in the Weatherby Formation range from Pennsylvanian to Late Triassic.

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Yang, Wentao, Te Fang, Yanpeng Wang et Hao Sha. « Late Paleozoic Tectonic Evolution of the Qinling Orogenic Belt : Constraints of Detrital Zircon U-Pb Ages from the Southern Margin of North China Block ». Minerals 12, n^o 7 (7 juillet 2022) : 864. http://dx.doi.org/10.3390/min12070864.

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The tectonic evolution of the Qinling Orogenic Belt in the Late Paleozoic has long been controversial, especially due to the limitation of the Mianlue Ocean subduction time. Basin formation and sedimentary development in the southern North China Block are closely related to the tectonic evolution of the Qinling Orogenic Belt, which is an effective entry point to study basin–mountain interaction. We present new detrital zircon U–Pb data from the Shihezi Formation in the Luonan area in the southern margin of the North China Block. The results show that the bottom sample has two major peaks at 288 Ma and 448 Ma, with weak peaks at 908, 1912 Ma and 2420 Ma. The top sample has one major peak at 297 Ma, with weak peaks at 1933 Ma and 2522 Ma. Combined with the published paleocurrent data and lithofacies paleogeography, the sediments of the bottom sample were sourced from the North Qinling Belt, Inner Mongolia Palaeo-Uplift and the basement of the North China Block. The top sample originated mainly from the Inner Mongolia Palaeo-Uplift and the basement of the North China Block. Comparing the obtained zircon U-Pb ages with the published relevant data in the North China Block, it is found that the provenance area shifted from the Qinling Orogenic Belt to the Inner Mongolia Paleo-Uplift in the Late Carboniferous–Permian, and the Qinling Orogenic Belt could hardly provide provenance for the southern North China Block in the Middle Permian. The uplift of the Qinling Orogenic Belt in the Late Carboniferous may be the continuation of Caledonian orogeny in the Early Paleozoic, whereas the uplift of the Inner Mongolia Palaeo-Uplift is related to the tectonic evolution of the Central Asian Orogenic Belt during the Late Paleozoic. This tectonic transformation occurred when the Qinling Orogenic Belt no longer supplied sediments to the southern North China Block in the Middle Permian, and the Mianlue Ocean subduction did not occur until at least the Late Permian.

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Mitchell, Gary C. « The Permian-Triassic Stratigraphy of the Northwest Paradox Basin Area, Emery, Garfield, and Wayne Counties, Utah ». Mountain Geologist 22, n^o 4 (1 octobre 1985) : 149–66. http://dx.doi.org/10.31582/rmag.mg.22.4.149.

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The Upper Permian and Lower Triassic rocks in the northwestern Paradox basin are closely related even though they are separated by a significant unconformity. Careful analysis of surface and subsurface data provides a framework to relate underlying units to deposition of suprajacent units. The Black Dragon Member of the Triassic Moenkopi Formation infilled the topography on the underlying Permian units. The thickness of the Black Dragon Member is inversely related to the thickness of the underlying White Rim Sandstone. The upper portion of the Black Dragon Member was deposited primarily in coastal marine environments with a very low westward depositional slope. An oolite-bearing carbonate shelf present during subsequent Sinbad Member deposition was also controlled, in part, by thickness distribution of the Permian White Rim Sandstone. The Torrey Member was deposited on the Sinbad Member in a fine-grained, elastic-dominated, low energy, very flat coastal environment. The Moody Canyon Member (uppermost Moenkopi) was deposited in a subaqueous environment, probably marine. The Emery uplift, a pre-White rim tectonic element, did not affect deposition of the White Rim, Kaibab or Moenkopi strata. The San Rafael Swell is a Laramide tectonic feature that is offset from and unrelated to the Emery uplift or deposition of the Permian and Triassic units.

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Liu, Shasha, Eun Young Lee, Jinliang Zhang, Michael Wagreich, Leqiang Zhao et Hui Liu. « Tectono-Paleogeographic Impact on the Permian Depositional Environment and Provenance around the Chaiwopu Depression in the Southern Junggar Basin, NW China ». Minerals 11, n^o 11 (8 novembre 2021) : 1237. http://dx.doi.org/10.3390/min11111237.

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The Chaiwopu Depression in the southern Junggar Basin is located between the West Bogda Mountains and the northeastern Tian Shan Mountains in northwest China. The intracontinental basin–mountain system was formed in the Central Asian Orogenic Belt during the Late Paleozoic. The Permian strata around the depression exhibits distinct variations, which provide significant information to understand its tectonic and depositional evolution. This study investigated six outcrop sites using lithological, sedimentological, and geochemical analyses. The representative lithology of the Lower Permian is submarine lava and pyroclastic flows on the northern margins and alluvial deposits near the southern margins. In the Middle Permian sequence, the extensive distribution of alternating shale and silt/sandstone with oil shale and carbonate indicates a lacustrine setting. The sediments are composed of felsic rock-forming minerals derived mainly from island arc settings. The source rock properties correspond to the Carboniferous volcanic terrain of northeastern Tian Shan. The Lower to Middle Permian source-to-sink system occurred in an incipient level of weathering and maturation, a simple recycling process, and arid to semi-arid climatic conditions. The characteristics and changes of the depositional environment and provenance can be understood in terms of implications of tectono-paleogeographic evolution associated with the West Bogda rifting and uplift.

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Geert, Konert, Abdulkader M. Afifi, Sa’id A. Al-Hajri et Henk J. Droste. « Paleozoic Stratigraphy and Hydrocarbon Habitat of the Arabian Plate ». GeoArabia 6, n^o 3 (1 juillet 2001) : 407–42. http://dx.doi.org/10.2113/geoarabia0603407.

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ABSTRACT The Paleozoic section became prospective during the early 1970s when the enormous gas reserves in the Permian Khuff reservoirs were delineated in the Gulf and Zagros regions, and oil was discovered in Oman. Since then, frontier exploration has targeted the Paleozoic System throughout the Middle East, driven by various economic considerations. The Paleozoic sequences were essentially deposited in continental to deep marine clastic environments at the Gondwana continental margin. Carbonates only became dominant in the Late Permian. The sediments were deposited in arid to glacial settings, reflecting the drift of the region from equatorial to high southern latitudes and back. Following late Precambrian rifting that formed salt basins in Oman and the Arabian Gulf region, the Cambrian-Devonian sequences were deposited on a peneplained continental platform. The entire region was affected by the Hercynian Orogeny, which climaxed during the Carboniferous. The orogeny manifested itself in a change in basin geometry, inversion tectonics, regional uplift and tectonism along the Zagros fault zone. This deformation caused widespread erosion of the Devonian-Carboniferous and older sections, and was probably caused by collision along the northern margin of Gondwana. The Paleozoic tectonic super cycle ended with the onset of break-up tectonics in the Permian, and the deposition of Khuff carbonates over the newly formed eastern passive margin. A major Paleozoic petroleum system embraces reservoir seal pairs spanning the Silurian to Permian sequences. Hydrocarbons occur in a variety of traps, and are sourced by the Silurian ‘hot shale’. A second petroleum system occurs in areas charged from upper Precambrian source rocks in the salt basins. Hydrocarbon expulsion estimates, taking into account secondary migration losses, suggest that some one trillion barrels of oil equivalent (BOE) may have been trapped from the Silurian ‘hot shale’ alone. However, the long and complex hydrocarbon geological evolution of the basin, combined with low acoustic contrasts between target rock units, difficult surface conditions, tight reservoirs, and deep subsurface environments, posed significant challenges to exploration and development. The critical success factor is the continuous innovative effort of earth scientists and subsurface engineers to find integrated technology solutions, that will render the Paleozoic plays economically viable.

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Duin, E. J. T., J. C. Doornenbal, R. H. B. Rijkers, J. W. Verbeek et Th E. Wong. « Subsurface structure of the Netherlands - results of recent onshore and offshore mapping ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 85, n^o 4 (décembre 2006) : 245–76. http://dx.doi.org/10.1017/s0016774600023064.

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AbstractThis paper presents depth maps for eight key horizons and seven thickness maps covering the onshore and offshore areas for the Late Permian to recent sedimentary section of the Netherlands. These maps, prepared in the context of a TNO regional mapping project, are supported by nine regional structural cross sections and a table summarizing the timing of tectonic activity from Carboniferous to recent. These new regional maps enable the delineation of various structural elements but also reveal the development of these elements through time with improved detail. Since the latest Carboniferous the tectonic setting of the Netherlands changed repeatedly. During successive tectonic phases several pre-existing structural elements were reactivated and new elements appeared. The various identified regional structural elements are grouped into six tectonically active periods: Late Carboniferous, Permian, Triassic, Late Jurassic, Late Cretaceous and Cenozoic. This study demonstrates that many structural elements and fault systems were repeatedly reactivated and that a clear distinction exists between long-lived elements, such as the Roer Valley Graben, and short-lived structural elements, such as the Terschelling Basin.

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Metcalfe, I. « Stratigraphic and tectonic implications of Triassic conodonts from northwest Peninsular Malaysia ». Geological Magazine 127, n^o 6 (novembre 1990) : 567–78. http://dx.doi.org/10.1017/s0016756800015454.

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AbstractThe Chuping Limestone of northwest Peninsular Malaysia, until recently considered entirely of Permian age, has yielded late Triassic (early Norian) conodonts. TheLimestone thus spans the time interval late Early Permian–Late Triassic and is in part equivalent to the Kodiang Limestone (Late Permian–Late Triassic) in Kedah andsimilar limestone sequences in south Thailand and north Sumatra. Early Late Triassic (Carnian) conodonts are also reported from pelagic limestones associated with bedded chertsof the Chert Member of the Semanggol Formation in Kedah. The Chert Member, previously considered of Middle Triassic age, is re-interpreted to represent Early, Middle and early Late Triassic deposition. The Triassic sedimentary rocks of the Malay Peninsula represent three distinct sedimentary regions: a stable shallow marine carbonate complex (ChupingLimestone, Kodiang Limestone), which forms part of an elongate carbonate platform on theSibumasu block; a deep water pelagic/turbidite basinal sequence (Semanggol Formation) which accumulated in either a foredeep basin or an intracratonic pull-apart basin related to strike-slip faulting; and a volcanic-sourced volcaniclastic basinal sequence on the East Malaya block (Semantan Formation and equivalents) which accumulated in either a forearc/intra-arc setting, or in a post-orogenic rift basin.

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Zhang, Shaohua, Chiyang Liu, Jianqiang Wang, Jianke Bai, Xiaochen Zhao, Long Zhang, Nan Jia, Lijun Song et Heng Peng. « Zircon U-Pb-Hf Isotopes, Biotite 40Ar/39Ar Geochronology, and Whole-Rock Geochemistry of the Baogeqi Gabbro in the Northern Alxa, Southernmost Central Asian Orogenic Belt ». Minerals 12, n^o 5 (23 mai 2022) : 656. http://dx.doi.org/10.3390/min12050656.

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The final closure time of the Paleo-Asian Ocean and the Permo-Carboniferous tectonic settings in the northern Alxa are very important but controversial tectonic issues. The geochronology and petrogenesis of mafic igneous rocks are superior in clarifying regional tectonic settings. Here, we report on zircon U-Pb-Hf isotopes, biotite 40Ar/39Ar geochronology and whole-rock geochemical data of the hornblende gabbro from the Baogeqi gabbro pluton in the northern Alxa. The LA-ICP MS U-Pb analysis of zircon grains from the hornblende gabbro yield a weighted mean age of 262.7 ± 2.3 Ma (2σ, MSWD = 0.74), manifesting that the Baogeqi gabbro pluton emplacement was during the late Middle Permian (Capitanian). The 40Ar/39Ar dating of biotite grains from the hornblende gabbro yields a plateau age of 231.3 ± 1.6 Ma (2σ, MSWD = 0.55), indicating that the Baogeqi gabbro pluton cooled to below 300 ℃ in the Triassic. The hornblende gabbro samples are calc-alkaline with metaluminous character, and show enrichment in large ion lithophile elements (e.g., Rb, Ba, Sr, and K) but depletion in Nb, Ta, P, Th, and Ti relative to primitive mantle. Combined with the positive zircon εHf(t) values (+4.9–+9.4), we suggest that the magmas formed from the partial melting of depleted mantle were metasomatized by slab-derived fluids. Together with regional geology, these geochemical data suggest that the Baogeqi gabbro pluton was formed in an intracontinental extension setting, further indicating that the Paleo-Asian Ocean in the northern Alxa was closed prior to the late Middle Permian (Capitanian), and this region was in a post-collision extensional setting during the Capitanian-Late Permian. In addition, the Triassic cooling of the gabbro pluton may be a record of the decline of the Capitanian-Late Permian post-collisional extension basin due to the far-field effect of subduction-collision during the closure of the Paleo-Tethys Ocean.

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Frederiksen, Susanne. « Quantitative dynamic modelling of basin development in the central and eastern North Sea region – coaxial stretching and strain localization ». Bulletin of the Geological Society of Denmark 49 (2 décembre 2002) : 95–108. http://dx.doi.org/10.37570/bgsd-2003-49-08.

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A new two-dimensional dynamic lithosphere model is used to simulate the Late Palaeozoic to end Danian evolution of the Norwegian-Danish Basin and the post Permian evolution of the Central North Sea including the Central Graben. The transient heat equation and the equations of motion are solved using the finite element method. The lithosphere deforms by brittle and ductile processes through an elasto-visco-plastic rheology depending on temperature, pressure, strain-rate and material parameters. Strain softening dependent on accumulated strain is incorporated. Deposition, erosion and compaction of sediments are simulated. Results show that it is possible to satisfy observations of crustal structure, sediment thickness and surface heat flow for both basins taking all major tectonic and thermal events into consideration. The evolution of the Norwegian-Danish Basin is modelled using a Late Carboniferous – Early Permian thermal event, main rift phase in Early Permian and a minor extensional phase in Triassic. For the Central North Sea two thermal and three tectonic events are simulated: Late Carboniferous – Early Permian and Middle Jurassic thermal events, Early Triassic and Late Jurassic extension, and Late Cretaceous compression. Results show that strain softening may lead to strain localization during extension and therefore may explain observations of upper mantle dipping reflectors in the North Sea. A pure shear dominated extensional regime may change into a simple shear system.

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Zhili, Luo, Jin Yizhong et Zhao Xikui. « The Emei Taphrogenesis of the upper Yangtze Platform in south China ». Geological Magazine 127, n^o 5 (septembre 1990) : 393–405. http://dx.doi.org/10.1017/s0016756800015156.

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AbstractThe Yangtze Platform (Yangtze Palaeoplate) drifted into the area of southern China following late Silurian tectonism. In late Palaeozoic to early Mesozoic time the Yangtze Platform was subjected to strong extensional movements in its southeastern region within Yunnan, Guizhou, Guangxi and Hunan provinces, and along its northwestern margin in the Songpan-Ganzi area. Taphrogenesis (intracontinental extension) began in Devonian times, climaxed with the late Permian eruption of the Emeishan basalts, and ended in mid Triassic times. Therefore, the senior author (LZL) has named this extension the ‘Emei Taphrogenesis’, a phenomenon that was constrained by the neighbouring tectonic units of the Yangtze Platform. The platform has been substantially affected by the early Palaeozoic south China fold zone along its eastern margin, and by the late Palaeozoic opening of the Tethys Ocean on the northwestern margin. This paper delineates the tectonic patterns associated with the Emei Taphrogenesis.

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Cashyap, S. M., et R. C. Tewari. « Depositional model and tectonic evolution of Gondwana basins ». Journal of Palaeosciences 36 (31 décembre 1987) : 59–66. http://dx.doi.org/10.54991/jop.1987.1561.

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The paper analyses the sedimentary evolution of Gondwana basins of the India peninsula based on lithofacies their association, dispersal and sedimentary characters from lowermost glacial Talchir (basal Permian) through Kharbari, Barakar, Barren Measure, Raniganj to Mahadeva (Middle Triassic). Particular attention is focused on the role of formative processes ad interaction of Tectonism and climate on sedimentary evolution and basin configuration.

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Şahin, Nazif, et Demir Altiner. « Testing of Permian – Lower Triassic stratigraphic data in a half-graben/tilt-block system : evidence for the initial rifting phase in Antalya Nappes ». Canadian Journal of Earth Sciences 56, n^o 11 (novembre 2019) : 1262–83. http://dx.doi.org/10.1139/cjes-2018-0169.

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Testing of Middle Permian – Lower Triassic stratigraphic data from the Antalya Nappes in a half-graben/tilt-block system has revealed the presence of episodic rifting events separated by periods of tectonic quiescence. Following a period of uplift during the Permian (Late Artinskian to Roadian), the basement rocks have been activated by displacement faults and several depocenters in half-graben-like asymmetrical basins began to be filled with Roadian to Wordian continental clastic deposits intercalated with coal and marine rocks. The Early Capitanian time was a period of tectonic quiescence. The second event occurred in Middle to Late Capitanian times and produced basaltic volcanic rocks intercalated in the shallow marine fossiliferous carbonate successions. Following the Lopingian (Wuchiapingian and Changhsingian) and Permian–Triassic boundary interval representing a long tectonic quiescence, the last rifting episode started with an abrupt facies change in the late Griesbachian. Variegated shales, limestones, volcanics, talus breccia, and debris flow deposits were laid down in a half-graben/tilt-block system. As normal faulting has become active, the deposition continued on the subsiding hanging wall side. The stratigraphic gap increased in magnitude as the erosional truncation has incised deeply the footwall side. This initial rifting phase in the Antalya Nappes is prior to the onset of a stronger and more continuous rifting event that occurred in the Anisian–Carnian interval including a variety of deepwater clastic and carbonate deposits, radiolarites containing sometimes blocks and clasts derived from the basin margins, and volcanic rocks carrying intraoceanic setting character.

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LEROSEY-AUBRIL, RUDY. « The Late Palaeozoic trilobites of Iran and Armenia and their palaeogeographical significance ». Geological Magazine 149, n^o 6 (27 avril 2012) : 1023–45. http://dx.doi.org/10.1017/s0016756812000179.

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AbstractThe Iranian territory is composed of a mosaic of tectonic units, several of which underwent in the Permian and Triassic periods a migration from northern Gondwana to southern Laurussia associated with the opening of the Neo-Tethys Ocean. Although this broad outline of Permo-Triassic palaeogeographical evolution of Iranian microplates is now widely accepted, the individual timing of migration of these blocks, and their biogeographical relationships, remain insufficiently known. Here I review the Late Palaeozoic record of trilobites in Iran and Armenia, and discuss their palaeobiogeographical affinities in an attempt to shed light on the Permian palaeogeographical evolution of Iranian and Armenian terranes. Seven Iranian or Armenian localities, representative of five tectonic units, have yielded Carboniferous and Permian trilobites. Ten species are recognized, including two new taxa, Persia praecox gen. nov. sp. nov. and Pseudophillipsia (s.l.) parvizii sp. nov. P. praecox is the only Carboniferous (Tournaisian) species. The others are Wordian to Wuchiapingian in age and can be separated into three morphological groups, probably representing clades. One is composed of representatives of Acropyge, while the two others (armenica-group and paffenholzi-group) comprise species of Pseudophillipsia. Only P. (s.l.) parvizii sp. nov. from the Zagros Mountains (Arabian Plate) is not attributed to one of these groups. The distribution of trilobites in Iran and Armenia strongly suggests that the Alborz, Central Iran and Transcaucasia microplates represented a single biogeographical unit in Middle and Late Permian times. Special relationships of this biochore with South China can also be stressed.

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Dawson, O. « Fusiline foraminiferal biostratigraphy and carbonate facies of the Permian Ratburi Limestone, Saraburi, central Thailand ». Journal of Micropalaeontology 12, n^o 1 (1 août 1993) : 9–33. http://dx.doi.org/10.1144/jm.12.1.9.

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Abstract. A succession of Permian carbonates outcropping along the highway north of Saraburi, central Thailand, has yielded a prolific and diverse fusiline-algal assemblage of Early Permian (Sakmarian) to early Late Permian (Midian) age. Six major units representing dominantly carbonate platform environments are recognised: turbidite and basin slope deposits, a platform margin algal reef, a back reef, an interior platform with patch reefs, a protected lagoon inner platform, and supratidal, dolomitised algal mats. Archaeolithoporella and Tubiphytes form major reef frameworks analogous to those described from the Middle Permian reefs of Trogkofel (southern Austria) and El Capitan (western Texas). The associated dasycladacean floras are assignable to the Eastern Circum-Pacific Realm, whilst the fusiline fauna has Arctic-Tethyan affinities in the Early Permian and Tethyan affinities in the Middle Permian. Eight fusuline assemblage zones are recognised and the Robustoschwagerina-Nagatoella Zone, representing the Sakmarian (early Artinskian) stage, is recorded for the first time from central Thailand. Phylogenetic studies of the fusulines, coupled with an examination of the diagenetic fabrics and field observations, indicate the presence of an unconformity during the late Early Permian-early Middle Permian, which may be correlatable with a worldwide eustatic sea-level fall or may be due to local tectonic movements.

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Li, Pengfei, Min Sun, Gideon Rosenbaum, Keda Cai, Chao Yuan, Fred Jourdan, Xiaoping Xia, Yingde Jiang et Yunying Zhang. « Tectonic evolution of the Chinese Tianshan Orogen from subduction to arc-continent collision : Insight from polyphase deformation along the Gangou section, Central Asia ». GSA Bulletin 132, n^o 11-12 (8 avril 2020) : 2529–52. http://dx.doi.org/10.1130/b35353.1.

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Abstract The Central Asian Orogenic Belt, as the largest accretionary orogen on Earth, is an ideal candidate to study the geodynamics of convergent plate boundaries through a prolonged period. The evolution of this orogen has been explained by different tectonic models, which incorporated one, or a combination, of the following mechanisms: lateral stacking of arc systems along major shear zones, arc amalgamation, oroclinal bending, and trench migration. Here we elucidate major mechanisms responsible for the tectonic evolution of the Central Asian Orogenic Belt, focusing on the Chinese Tianshan Orogen in the southern Central Asian Orogenic Belt. Structural observations from the ∼50-km-long Gangou section show evidence of polyphase deformation. The earliest episode of orogen-parallel sinistral shearing, constrained to the Early Devonian (ca. 399 Ma) by syn-deformational intrusions, was possibly controlled by oblique subduction. This was followed by an episode of ∼NE–SW contractional deformation, dated at ca. 356 Ma (40Ar/39Ar age of syn-deformational hornblende), and likely associated with an episode of trench advance. The third stages of deformation during the latest Carboniferous and Permian involved ∼NE-SW contraction, orogen-parallel extension, and dextral transpression. Our new geochronological data constrain the timing of orogen-parallel extension to ca. 303–293 Ma, and confirm that dextral activation along shear zones occurred during the Permian. The results highlight the role of trench migration, oblique tectonics, and syn-collisional orogen-parallel extension in the build-up of the Central Asian Orogenic Belt, and contribute to the pre-collisional reconstruction of this orogenic system.

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Vetrov, Evgeny, Johan De Grave, Natalia Vetrova, Fedor Zhimulev, Simon Nachtergaele, Gerben Van Ranst et Polina Mikhailova. « Tectonic History of the South Tannuol Fault Zone (Tuva Region of the Northern Central Asian Orogenic Belt, Russia) : Constraints from Multi-Method Geochronology ». Minerals 10, n^o 1 (9 janvier 2020) : 56. http://dx.doi.org/10.3390/min10010056.

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In this study, we present zircon U/Pb, plagioclase and K-feldspar 40Ar/39Ar and apatite fission track (AFT) data along the South Tannuol Fault Zone (STFZ). Integrating geochronology and multi-method thermochronology places constraints on the formation and subsequent reactivation of the STFZ. Cambrian (~510 Ma) zircon U/Pb ages obtained for felsic volcanic rocks date the final stage of STFZ basement formation. Ordovician (~460–450 Ma) zircon U/Pb ages were obtained for felsic rocks along the structure, dating their emplacement and marking post-formational local magmatic activity along the STFZ. 40Ar/39Ar stepwise heating plateau-ages (~410–400 Ma, ~365 and ~340 Ma) reveal Early Devonian and Late Devonian–Mississippian intrusion and/or post-magmatic cooling episodes of mafic rocks in the basement. Permian (~290 Ma) zircon U/Pb age of mafic rocks documents for the first time Permian magmatism in the study area creating prerequisites for revising the spread of Permian large igneous provinces of Central Asia. The AFT dating and Thermal history modeling based on the AFT data reveals two intracontinental tectonic reactivation episodes of the STFZ: (1) a period of Cretaceous–Eocene (~100–40 Ma) reactivation and (2) the late Neogene (from ~10 Ma onwards) impulse after a period of tectonic stability during the Eocene–Miocene (~40–10 Ma).

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Vozárová, Anna, Katarína Šarinová, Dušan Laurinc, Elena Lepekhina, Jozef Vozár, Nickolay Rodionov et Pavel Lvov. « Exhumation history of the Variscan suture : Constrains on the detrital zircon geochronology from Carboniferous–Permian sandstones (Northern Gemericum ; Western Carpathians) ». Geologica Carpathica 70, n^o 6 (1 décembre 2019) : 512–30. http://dx.doi.org/10.2478/geoca-2019-0030.

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Abstract The Late Paleozoic sedimentary basins in the Northern Gemericum evolved gradually in time and space within the collisional tectonic regime of the Western Carpathian Variscan orogenic belt. The detrital zircon age spectra, obtained from the Mississippian, Pennsylvanian and Permian metasediments, have distinctive age distribution patterns that reflect the tectonic setting of the host sediments. An expressive unimodal zircon distribution, with an age peak at 352 Ma, is shown by the basal Mississippian metasediments. These represent a relic of the convergent trench-slope sedimentary basin fill. In comparison, the Pennsylvanian detrital zircon populations display distinct multimodal distributions, with the main age peaks at 351, 450, 565 Ma and smaller peaks at ~2.0 and ~2.7 Ga. This is consistent with derivation of clastic detritus from the collisional suture into the foreland basin. Similarly, the Permian sedimentary formations exhibit the multimodal distribution of zircon ages, with main peaks at 300, 355 and 475 Ma. The main difference, in comparison with the Pennsylvanian detrital zircon assemblages, is the sporadic occurrence of the Kasimovian– Asselian (306–294 Ma), as well as the Artinskian–Kungurian (280–276 Ma) igneous zircons. The youngest magmatic zircon ages nearly correspond to the syn-sedimentary volcanic activity with the depositional age of the Permian host sediments and clearly indicate the extensional, rift-related setting.

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Środoń, J., et N. Clauer. « Diagenetic history of Lower Palaeozoic sediments in Pomerania (northern Poland), traced across the Teisseyre–Tornquist tectonic zone using mixed– layer illite– smectite ». Clay Minerals 36, n^o 1 (mars 2001) : 15–27. http://dx.doi.org/10.1180/000985501547321.

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AbstractMixed-layer illite-smectite from Lower Palaeozoic sedimentary rocks, on both sides of the Teisseyre–Tornquist tectonic zone (TTZ) in northern Poland, was studied by X-ray diffraction and dated by K-Ar means.The percentage of smectite layers in illite-smectite (%S) indicates maximum palaeotemperatures of 125–135°C at the surface of Lower Palaeozoic rocks on the craton (NE of TTZ), and 110 to ≤180°C in different tectonic blocks to the SW of TTZ (area of Caledonian consolidation). The vertical changes in the %S indicate that the maximum palaeotemperatures were reached before Permian time on the craton, and before Jurassic, Triassic, Permian or Carboniferous periods but after the beginning of Devonian time in the Caledonian zone. The K—Ar ages of bentonites indicate that the maximum palaeotemperatures were reached by 370—390 Ma or even slightly earlier (Middle—late Devonian). A maximum of 3—6 km of Silurian–Devonian cover on the craton and in the TTZ is suggested by the data.

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Kontorovich, V. A., A. E. Kontorovich, A. Yu Kalinin, L. M. Kalinina, V. V. Lapkovskii, B. L. Lunev, S. A. Moiseev et M. V. Solovev. « Seismogeologic, Structural, and Tectonic Characteristics of the Continental Margin of the Siberian Platform (Khatanga–Lena Interfluve) ». Russian Geology and Geophysics 62, n^o 08 (1 août 2021) : 947–63. http://dx.doi.org/10.2113/rgg20214352.

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Abstract —The paper considers the seismogeologic, structural, and tectonic features of Neoproterozoic–Paleozoic and Mesozoic sedimentary complexes in the Arctic regions of the Siberian Platform. Based on the results of deep drilling, the geologic structure of the study area was analyzed, and the key sections of Neoproterozoic–Paleozoic deposits of the Anabar–Khatanga and Lena–Anabar oil and gas areas (OGA) were compiled. Analysis of geological and geophysical materials showed the existence of a sedimentary basin up to 14–16 km in thickness on the continental margin of the Siberian Platform, with five regional seismogeologic megacomplexes in its section: Riphean, Vendian, lower–middle Paleozoic, Permian, and Mesozoic. Based on the results of a complex interpretation of CDP seismic-survey and deep-drilling data, a structural and tectonic analysis was performed, structural maps were compiled for all reference stratigraphic levels, and a conclusion has been drawn about the similarity of the structural plans of the Riphean top and overlying sedimentary complexes. Using a structural map along the Permian top, a tectonic map of the study area was compiled, which corresponds to the current state of study. The results of numerical modeling of the salt diapir formation processes are presented, and the types of anticlinal structures, potential oil- and gas-promising objects, are considered.

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Chen, Li Min, Hao Xu et You Fei Li. « Types of Coal-Bearing Basin and Tectonic Unit in the Northwest Coal Hosting Area ». Advanced Materials Research 1092-1093 (mars 2015) : 1497–500. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.1497.

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Coal is typical of sedimentary deposits, Occurrence in a coal basin. The original nearly horizontal continuous coal seam was divided into different size; different depth containing coal segment by late tectonic movement, but its scope is not affected by today's "basin" restrictions. With the concept of coal occurrence tectonic unit to reflect the current Coal Occurrence Characteristics and build a prototype coal basin types that prototype into a coal basin tectonic movement after the formation of today's coal occurrence tectonic unit. In Northwest coal hosting area, the main coal bearing strata include Carboniferous-Permian, Upper Triassic, Lower-Middle Jurassic and Lower Cretaceous, and its distribution is regular; the center and strength of coal accumulation were variation in different coal-forming period; the types of basin are multiple, including Passive Margins, Peripheral Foreland, Intracontinental Rift, Intermontane, Strike-slip pull-apart, Strike-slip pull-apart, Inter-montane; moreover, one belt and two rings constitute the tectonic framework of Northwest coal hosting area.

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Xu, Wentao, Fulai Liu, Wang Xu, Huining Wang, Lei Ji, Fang Wang et Dan Wang. « Geochemical and Geochronological Constraints of Permian-Triassic Magmatism on Oceanic Subduction and Continental Collision during the Eastern Paleo-Tethyan Evolution ». Minerals 12, n^o 5 (17 mai 2022) : 633. http://dx.doi.org/10.3390/min12050633.

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The Jinshajiang–Ailaoshan–Song Ma orogenic belt (JASB), as a vital segment of the eastern Paleo-Tethyan tectonic zone, is one of the most important zones in which to study the Paleo-Tethyan tectonic evolution. We have undertaken an integrated geochronological, petrological, and geochemical study of mafic rocks from the JASB to reveal the subduction and closure processes of the eastern Paleo-Tethyan Ocean during the Permian to Triassic. In conjunction with previous magmatic and metamorphic records in the JASB, three important tectonic stages are identified: (1) Early Permian to Early Triassic (ca. 288–248 Ma). Most of the Early Permian to Early Triassic mafic rocks have normal mid-ocean ridge basalt (N-MORB)- or enriched MORB (E-MORB)-like rare earth elements (REE) and trace element-normalized patterns with positive εNd(t) and εHf(t) values and negative Nb and Ta anomalies. Their La/Nb ratios and εNd(t) values show that approximately 3%–15% of slab-derived fluid accounts for the generation of these rocks. These characteristics suggest that the mafic rocks formed in an arc/back-arc basin setting at this stage. Additionally, the Early Permian mafic rocks are mainly exposed in the Jomda–Weixi–Yaxuanqiao–Truong Son magmatic rock belt (JYTB) on the western side of the JASB, indicating that the westward subduction of the Jinshajiang–Ailaoshan–Song Ma Paleo-Tethys Ocean (JASO) began in the Early Permian. Middle Permian mafic rocks are exposed in the Ailaoshan-Day Nui Con Voi metamorphic complex belt and the JYTB on both sides of the JASB. We propose that the bipolar subduction of the JASO occurred in the Middle Permian and ended in the Early Triassic. (2) Middle Triassic (ca. 248–237 Ma). The mafic rocks at this stage have LREE- and LILE-enriched patterns, negative Nb and Ta anomalies and negative εNd(t) values. Their variable εHf(t), εNd(t) values and La/Nb ratios show that these mafic rocks were highly affected by crustal material (ca. 16%). Considering the Middle Triassic high-pressure (HP) metamorphism and massive Al-enriched felsic magmatism in the JASB, these rocks may have formed in a collisional setting between the South China Block (SCB) and the North Qiangtang–Simao–Indochina Block (QSIB) during the Middle Triassic. (3) Late Triassic (ca. 235–202 Ma). The mafic rocks at this stage have negative εNd(t) and εHf(t) values and show terrestrial array characteristics. The εNd(t) values and La/Nb ratios show that approximately 30% of crustal components account for the generation of these rocks. Combined with the contemporaneous bimodal magma and metamorphism during the Late Triassic, we suggest that these rocks may have formed in a postcollisional extensional setting associated with magma diapir.

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Cassinis, G., et C. R. Perotti. « A stratigraphic and tectonic review of the Italian Southern Alpine Permian ». Palaeoworld 16, n^o 1-3 (janvier 2007) : 140–72. http://dx.doi.org/10.1016/j.palwor.2007.05.004.

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Tremblay, Alain, et Nicolas Pinet. « Late Neoproterozoic to Permian tectonic evolution of the Quebec Appalachians, Canada ». Earth-Science Reviews 160 (septembre 2016) : 131–70. http://dx.doi.org/10.1016/j.earscirev.2016.06.015.

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Robertson, Alastair H. F., Osman Parlak et Timur Ustaömer. « Permian–Recent palaeogeographical and tectonic development of Anatolia : some recent contributions ». International Journal of Earth Sciences 105, n^o 1 (16 octobre 2015) : 1–5. http://dx.doi.org/10.1007/s00531-015-1247-2.

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Audibert, Mark, et Mikhail L. Bazhenov. « Permian paleomagnetism of the northern Tien Shan and its tectonic implications ». Tectonics 11, n^o 5 (octobre 1992) : 1057–70. http://dx.doi.org/10.1029/92tc01004.

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Altiner, Demir, Sevinç Özkan-Altiner et Ali Koçyiğit. « Late Permian Foraminiferal Biofacies Belts in Turkey : Palaeogeographic and Tectonic Implications ». Geological Society, London, Special Publications 173, n^o 1 (2000) : 83–96. http://dx.doi.org/10.1144/gsl.sp.2000.173.01.04.

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Zhang, Shuncun, Tao Wang, Hui Guo, Shengyin Zhang et Bo Chen. « Lipid Biomarker and Stable Isotopic Profiles through Late Carboniferous–Early Triassic of the Deepest Well MS-1 in the Junggar Basin, Northwest China ». Minerals 12, n^o 10 (15 octobre 2022) : 1299. http://dx.doi.org/10.3390/min12101299.

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The Carboniferous–Triassic period was an important stage of global sea–land transformation, with coal formation in the Carboniferous, biological extinction at the end of the Permian, and global drought in the Triassic. The MS-1 well in the Mosuowan High of the Junggar Basin is the deepest well drilled in Northwestern China. In this paper, we investigate the sedimentary environment and climate evolution of the Mosuowan area in the central Junggar Basin during the Late Carboniferous–Early Permian by the petrothermal, lipid biomarker, and isotopic composition of mud shale core samples, and explore the tectonic–climatic events and Central Asian orogenic belt evolution driving the sedimentary environment. The study shows that the organic matter from the Upper Carboniferous to the Lower Permian is at a mature stage, but biomarkers maintained the primary information although the organic matter was subjected to thermal evolution. In the late Carboniferous period (Tamugan Formation), the study area was a closed remnant sea with a relatively humid climate, triggering lush terrestrial vegetation and high organic carbon content in the sediments, which had the potential to evolve into natural gas. During the Xiazijie Formation of the Middle Permian, tectonic activity shifted to the subsidence period, and the salinity of the water decreased after a large input of fresh water. The lake basin area expanded, and the content of aquatic organisms continued to increase. As the Lower Permian stratigraphy is missing, this sea–land transition seems to jump. The low and upper Urho Formations of the Middle–Upper Permian are a deltaic foreland deposit, and geochemical indicators show an overall lake retreat process with a continuous increase in organic matter content of terrestrial origin. The lithologic assemblage of the Triassic Baikouquan Formation is braided river deltaic sedimentation with migration of deposition centers of the lake basin. In conclusion, the Late Carboniferous–Early Permian period was influenced by global changes, Paleo-Asian Ocean subduction, and continental splicing, which resulted in a continuous increase in terrestrial organic matter, water desalination, and oxidation-rich sediments in the Mosuowan region, but the P–T biological mass extinction event was not recorded.

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Li, Bin, Qiqi Li, Wenhua Mei, Qingong Zhuo et Xuesong Lu. « Analysis of accumulation models of Middle Permian in Northwest Sichuan Basin ». Earth Sciences Research Journal 24, n^o 4 (26 janvier 2021) : 419–28. http://dx.doi.org/10.15446/esrj.v24n4.91149.

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Great progress has been made in middle Permian exploration in Northwest Sichuan in recent years, but there are still many questions in understanding the hydrocarbon accumulation conditions. Due to the abundance of source rocks and the multi-term tectonic movements in this area, the hydrocarbon accumulation model is relatively complex, which has become the main problem to be solved urgently in oil and gas exploration. Based on the different tectonic backgrounds of the middle Permian in northwest Sichuan Basin, the thrust nappe belt, the hidden front belt, and the depression belt are taken as the research units to comb and compare the geologic conditions of the middle Permian reservoir. The evaluation of source rocks and the comparison of hydrocarbon sources suggest that the middle Permian hydrocarbon mainly comes from the bottom of the lower Cambrian and middle Permian, and the foreland orogeny promoted the thermal evolution of Paleozoic source rocks in northwest Sichuan to high maturity and over maturity stage. Based on a large number of reservoir physical properties data, the middle Permian reservoir has the characteristics of low porosity and low permeability, among which the thrust nappe belt and the hidden front belt have relatively high porosity and relatively developed fractures. The thick mudstone of Longtan formation constitutes the regional caprock in the study area and the preservation condition is good as a whole. However, the thrusting faults destroyed the sealing ability of the caprock in the nappe thrust belt. Typical reservoir profiles revealed that the trap types were different in the study area. The thrust fault traps are mainly developed in the thrust nappe belt, while the fault anticline traps are developed in the hidden front belt, and the structural lithological traps are developed in the depression belt. The different structural belts in northwest Sichuan have different oil and gas accumulation models, this paper built three hydrocarbon accumulation models by the analysis of reservoir formation conditions. The comprehensive analysis supposed the hidden front belt is close to the lower Cambrian source rock, and the reservoir heterogeneity is weak, faults connected source rock is developed, so it is a favorable oil and gas accumulation area in the middle Permian.

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Koehl, Jean-Baptiste P., John E. A. Marshall et Gilda Lopes. « The timing of the Svalbardian Orogeny in Svalbard : a review ». Solid Earth 13, n^o 8 (30 août 2022) : 1353–70. http://dx.doi.org/10.5194/se-13-1353-2022.

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Abstract. In the Late Devonian to earliest Mississippian, Svalbard was affected by a short-lived episode of deformation named the Svalbardian Orogeny. This event resulted in intense folding and thrusting in Devonian sedimentary successions. Deformation stopped prior to the deposition of Carboniferous to Permian sedimentary strata of the Billefjorden and Gipsdalen groups, which lie unconformably over folded Devonian strata. Later on, presumed Svalbardian structures were reworked during Eurekan tectonism in the early Cenozoic and partly eroded. At present, records of Svalbardian deformation are only preserved in narrow N–S-trending belts in central, northern, western, and southern Spitsbergen. Despite extensive field studies, the timing of the Svalbardian Orogeny is poorly constrained and remains a matter of debate in places because of conflicting ages and because of the complex tectonic history of Svalbard. The present contribution aims at reviewing and discussing all available age constraints for Svalbardian tectonism, including notably palynological, paleontological, and geochronological evidence. This has great implications for the plate tectonic reconstructions of Arctic regions and for the tectonic history of Svalbard. Palynological and paleontological evidence suggest that the Mimerdalen Subgroup is upper Givetian to lower Frasnian (ca. 385–380 Ma) in age and that the Billefjorden Group is mid-Famennian to Upper Mississippian (ca. 365–325 Ma) in age, constraining the Svalbardian event in central and northern Spitsbergen to 383–365 Ma if it ever occurred. Palynological ages indicate that the Adriabukta Formation in southern Spitsbergen is Middle Mississippian and therefore cannot have been involved in the Svalbardian event, thus suggesting that all the deformation in southern Spitsbergen is early Cenozoic in age and that strain-partitioning processes had a major role in localizing deformation in weaker stratigraphic units. The few geochronological age constraints yielding Late Devonian–Mississippian ages in Svalbard may reflect either Svalbardian contraction or extensional processes and are therefore of no use to validate or invalidate the occurrence of the Svalbardian event. On the contrary, the contradicting lines of evidence used to support the occurrence of the Svalbardian event and new regional geophysical studies suggest that Svalbard was subjected to continuous extension from the late Silurian to early Permian times.

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ZENG, QING-DONG, YAN SUN, XIAO-XIA DUAN et JIAN-MING LIU. « U–Pb and Re–Os geochronology of the Haolibao porphyry Mo–Cu deposit, NE China : implications for a Late Permian tectonic setting ». Geological Magazine 150, n^o 6 (26 avril 2013) : 975–85. http://dx.doi.org/10.1017/s0016756813000186.

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AbstractNew geochronological data for the Haolibao porphyry Mo–Cu deposit, NE China, yield Permian crystallization zircon U–Pb ages of 278 ± 5 Ma for granite and 267 ± 10 Ma for the granite porphyry that hosts the Mo–Cu mineralization, and four Re–Os molybdenite ages yield an isochron age of 265 ± 3 Ma. These ages disagree with the previous K–Ar age determinations that suggest a correlation of intrusive rocks of the Haolibao area with the Yanshanian intrusive rocks of Cretaceous age. The mineralizations at the Haolibao area may be related to the tectonic–magmatic activity caused by collisional events between the North China Plate and Mongolian terranes during the Permian. The occurrence of the Haolibao plutonic rocks indicates that the Palaeo-Asian-Mongolian Ocean closed during the Permian along the Xilamulun River suture.

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Удодов, Юрий, Yurii Udodov, Надежда Егорова, Nadezhda Egorova, Г. Багмет et G. Bagmet. « GEOLOGICAL-GEOMORPHOLOGICAL CHARACTERISTICS AND NATURAL RESOURCES OF THE KEMEROVO REGION ». Bulletin of Kemerovo State University. Series : Biological, Engineering and Earth Sciences 2017, n^o 1 (25 juin 2017) : 53–59. http://dx.doi.org/10.21603/2542-2448-2017-1-53-59.

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<p>The article deals with the geological structure, geomorphic features and mineral resources ofKemerovoregion. It describes stratified formation of late Precambrian (Riphean and Vendian), Paleozoic, Mesozoic and Cenozoic eras. The article considers four main tectono-magmatic stages of geological development of the area (posteritas-early Ordovician, Ordovician-Silurian, Devonian-late Permian and late Permian-Mesozoic). It enumerates the characteristics of the major tectonic elements of the Kuznetsk Alatau and Mountain Shoria, Salair and Tom ' -Kolyvan areas of the Kuznetsk coal basin. It lists deposits of iron, manganese, polymetallic lead-zinc and copper ore, aluminum raw materials. One of the oldest and valuable minerals of the region is gold. The coalbearing formations of the Kuznetsk coal basin described in the article are the largest of all the exploited coal basins of the world, in terms of reserves and quality of coal. The article lists non-metallic minerals, and the geography of their fields. It describes the main morphostructural elements: the Salair ridge, Alatau-Shor highlands, Tom ' -Kolyvan hill, the Kuznetsk basin and theChulymvalley.</p>

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Brew, Graham, Muawia Barazangi, Ahmad Khaled Al-Maleh et Tarif Sawaf. « Tectonic and Geologic Evolution of Syria ». GeoArabia 6, n^o 4 (1 octobre 2001) : 573–616. http://dx.doi.org/10.2113/geoarabia0604573a.

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ABSTRACT Using extensive surface and subsurface data, we have synthesized the Phanerozoic tectonic and geologic evolution of Syria that has important implications for eastern Mediterranean tectonic studies and the strategies for hydrocarbon exploration. Syrian tectonic deformation is focused in four major zones that have been repeatedly reactivated throughout the Phanerozoic in response to movement on nearby plate boundaries. They are the Palmyride Mountains, the Euphrates Fault System, the Abd el Aziz-Sinjar uplifts, and the Dead Sea Fault System. The Palmyrides include the SW Palmyride fold and thrust belt and two inverted sub-basins that are now the Bilas and Bishri blocks. The Euphrates Fault System and Abd el Aziz-Sinjar grabens in eastern Syria are large extensional features with a more recent history of Neogene compression and partial inversion. The Dead Sea transform plate boundary cuts through western Syria and has associated pull-apart basins. The geological history of Syria has been reconstructed by combining the interpreted geologic history of these zones with tectonic and lithostratigraphic analyses from the remainder of the country. Specific deformation episodes were penecontemporaneous with regional-scale plate-tectonic events. Following a relatively quiescent early Paleozoic shelf environment, the NE-trending Palmyride/Sinjar Trough formed across central Syria in response to regional compression followed by Permian-Triassic opening of the Neo-Tethys Ocean and the eastern Mediterranean. This continued with carbonate deposition in the Mesozoic. Late Cretaceous tectonism was dominated by extension in the Euphrates Fault System and Abd el Aziz-Sinjar Graben in eastern Syria associated with the closing of the Neo-Tethys. Repeated collisions along the northern Arabian margin from the Late Cretaceous to the Late Miocene caused platform-wide compression. This led to the structural inversion and horizontal shortening of the Palmyride Trough and Abd el Aziz-Sinjar Graben.

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