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Explanatory notes for the Tectonic Map of the Kara and Laptev Seas and Northern Siberia (Scale: 1:2 500 000) // M.: Institute of Lithosphere of Marginal Seas RAS, 1998. – 116 p.

Authors:
  • Polar geophysical Institute

Abstract

Тектоническая карта морей Карского и Лаптевых и севера Сибири масштаба 1:2 500 ООО охватывает акватории шельфовых морей и южное окончание Евразийского бассейна Северного Ледовитого океана, а также многочисленные острова и прилегающую часть суши. В пределах карты выделяются следующие основные структурные элементы. В центре расположен Сибирский кратон с фундаментом протерозойского возраста. Наиболее древние породы фундамента в пределах карты обнажаются в Анабарском щите и в Оленекском поднятии. Породы основания перекрыты осадочным и вулканогенным чехлом, среди которого особое место занимает трапповая формация и одновозрастные с ней щелочноультраосновные интрузии, а также кимберлиты. В пределах кратона установлены импактные структуры. К западу от Сибирского кратона располагается ЗападноСибирский бассейн, структура которого осложнена триасовыми рифтами. Дно Карского моря в восточной части слагает гренвильская Карская плита, структуры которой поднимаются над уровнем моря в пределах многочисленных островов, в том числе, архипелагов Северной Земли и Нордшельда. На юге Карская плита граничит по Центрально-Таймырскому аккреционному поясу с Сибирским кратоном, а на востоке - с Южно-Карской субокеанической впадиной и гренвильской Свальдбарской плитой. К востоку от Карской плиты в пределах моря Лаптевых расположена северо-восточная окраина Сибирского кратона, подтвергшаяся сложным деформациям в мезо-кайнозойское время. От структур Евразийской впадины и хребта Гаккеля шельф кратона отделен трансформным разломом Чарли. Анализируется нефтегазоносность региона. Объяснительная записка объемом 127 стр., 36 илл., библ. 281 назв. Карта и разрезы к ней на 2 листах.
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... The eastern boundary with the Anabar-Lena CTSE (Khudoley et al. 2021) is traced along a zone of abrupt thinning of Mesozoic sediments. The Siberian Craton, as a part of Rodinia, had a developed Mesoproterozoic-early Neoproterozoic passive continental margin (Vernikovsky 1996;Bogdanov et al. 1998;Pisarevsky and Natapov 2003;Vernikovsky et al. 2004). Mesoproterozoic strata of the CTSE, using analogies with coeval formations of the Siberian Craton, could consist of carbonate and siliciclastic sediments (Fig. 3). ...
... Pogrebitsky (1971) connected the cause this change to the Taimyr Orogeny, which culminated in the early Permian. Modern structural, petrological, geochronological and palaeomagnetic data prove conclusively that this change in sedimentation was related to the collision of the Siberian Craton with the Kara microcontinent (Vernikovsky 1992(Vernikovsky , 1996Vernikovsky et al. 1995;Bogdanov et al. 1998;Metelkin et al. 2000Metelkin et al. , 2005Metelkin et al. , 2015Khain 2001). Strike-slip zones with large displacements, along which the Kara microcontinent was 'sliding' during the entire early Paleozoic, finally led to the collision of the Kara and Siberian plates, and to the subsequent formation of the imbricated Taimyr-Severnaya Zemlya FTB and growth of the related orogen (Metelkin 2012). ...
... A possible cause of the Late Jurassic-Early Cretaceous inversion of the CTSE could be related to the late Mesozoic collision of the Kolyma-Omolon Superterrane with the eastern margin of the Siberian Craton and formation of the Verkhoyansk FTB east of the CTSE. This compressional deformation from the SE affected the Yenisei-Khatanga CTSE, especially its eastern part, where it caused the formation of a system of elongated swells (Bogdanov et al. 1998). It is also possible that the counter-clockwise rotation of the Siberian Craton was another cause of the inversion and transpressive deformation of the Mesozoic infill of the Yenisei-Khatanga CTSE at the Jurassic-Cretaceous boundary (Timofeev et al. 2011). ...
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The Yenisei-Khatanga Composite Tectono-Sedimentary Element (YKh CTSE) is located between the Siberian Craton and the Taimyr-Severnaya Zemlya fold-and-thrust belt. The total thickness of the Mesoproterozoic-Cenozoic sediments of YKh CTSE reaches 20 to 25 km. They are divided into four tectono-sedimentary elements (TSE): (i) Mesoproterozoic-early Carboniferous Siberian Craton continental margin, (ii) middle Carboniferous-Middle Triassic syn-orogenic Taimyr foreland basin, (iii) late Permian-Early Triassic syn-rift, and (iv) Triassic-Early Paleocene post-rift. The last one is the most important in terms of its petroleum potential and is the most drilled part of the CTSE. Its thickness accounts for half of the total thickness of YKh CTSE. The margins of the post-rift TSE and the inner system of inversion swells and adjacent troughs and depressions were shaped by three tectonic events: (i) middle Carboniferous-Middle Triassic Taimyr orogeny, (ii) Late Jurassic-Early Cretaceous Verkhoyansk orogeny, (iii) Late Cenozoic uplift. These processes led to more intense migration of hydrocarbons, the trap formation and their infill with hydrocarbons. Triassic, Jurassic, and Lower Cretaceous source rocks are mostly gas-prone, and among 20 discovered fields in Jurassic and Cretaceous plays, 17 are gas or mixed-type fields.
... The structures of the north-western margin of the Siberian craton have attracted the attention of geologists for over a hundred years [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] and many others. The earliest and most essential questions on the study area are: (a) How did the Taimyr-Severnaya Zemlya folded area form-a key structure of the Artic, and is it a part of the Siberian craton; (b) what are the sequence and stages of its formation, how is the formation of this folded area related to the formation of the Yenisei-Khatanga basin; (c) what serves as the basement for the latter. ...
... Tectonic map of the north-western part of the Siberian craton, the Taimyr folded area and the Yenisei-Khatanga basin. Composed using References [5,6] with additions by the authors. 1-boundary of the Yenisei-Khatanga basin along outcrops of Early Jurassic and younger rocks; 2-Kara microcontinent (a) including metamorphosed and deformed flyschoid passive margin sediments (NP-Є) of the North Taimyr Zone (b); 3-7-the Central Taimyr accretionary belt: 3-gneiss complexes of cratonic terranes with 940-850 Ma granitoids; 4-terranes of carbonate shelves (MP(?)-NP); 5-island arc terranes, ophiolites and plagiogranites (750-630 Ma), and accretionary wedge complexes; 6-molasses (NP), carbonate, black shales, shelf and hemipelagic sediments (NP 3 -C); 7-offshore part of the belt; 8-syncollisional (306-300 Ma) and postcollisional (264-258 Ma) granites; 9-depths of the Siberian craton crystalline basement and of the deformed, mostly Paleozoic rocks within the Yenisei-Khatanga basin and the West Siberian basin; 10-isohypses (depth in km) of the seismic basement roof: (a)-established, (b)-inferred; 11-13-Siberian traps (P 2 -T 1 ): 11-dolerites and their differentiates; 12-alkaline ultramafic rocks and carbonatites; 13-flood basalts and associating volcanogenic-sedimentary deposits; 14-zones of continental rifting and range formation: I-Tanama-Malokhet, II-Rassokhin and III-Balakhnin from [17] 2-sandy-argillaceous sediments; 3-mudstones, and shales; 4-limestones; 5-dolomites; 6-basalts, tuffs, terrigenous rocks (P 2 -T 1 ); 7-folded structure of the crystalline basement Kara microcontinent (shown figuratively); 8-gneiss-granite and granulite-mafic complexes of the crystalline basement; 9-faults; 10-roof of the seismic basement: (a) Established, (b) inferred from indirect data and single observations. ...
... According to results of deep seismic sounding, the Moho boundary depth under the Yenisei-Khatanga basin varies from 27-33 km in the central part to 36-38 km under the North-Siberian monocline and to 40-43 km under Taimyr [6,23,24]. The crystalline basement is supposedly composed of metamorphic rocks of Archean-Paleoproterozoic age. ...
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The geodynamic development of the northwestern (Arctic) margin of the Siberian craton is comprehensively analyzed for the first time based on our database as well as on the analysis of published material, from Precambrian-Paleozoic and Mesozoic folded structures to the formation of the Mesozoic-Cenozoic Yenisei-Khatanga sedimentary basin. We identify the main stages of the region's tectonic evolution related to collision and accretion processes, mainly subduction and rifting. It is demonstrated that the prototype of the Yenisei-Khatanga basin was a wide late Paleozoic foreland basin that extended from Southern Taimyr to the Tunguska syneclise and deepened towards Taimyr. The formation of the Yenisei-Khatanga basin, as well as of the West-Siberian basin, was due to continental rifting in the Permian-Triassic. The study describes the main oil and gas generating deposits of the basin, which are mainly Jurassic and Lower Cretaceous mudstones. It is shown that the Lower Cretaceous deposits contain 90% of known hydrocarbon reserves. These are mostly stacked reservoirs with gas, gas condensate and condensate with rims. The study also presents data on oil and gas reservoirs, plays and seals in the Triassic, Jurassic and Cretaceous complexes.
... He also identified the Anabar-Khatanga Saddle (AKhS) as a separate structural domain located between the Khatanga and Anabar rivers, later often referred to as the Khatanga Saddle. However, on more recent tectonic maps, the AKhS has been included in the Anabar-Lena Basin and not shown as a separate structure (Parfenov 1990;Bogdanov et al. 1998). Nowadays, both structures are usually separated from each other, and the area between the Anabar and Lena rivers is usually called the Anabar-Lena (or, sometimes, Lena-Anabar) Basin or Province, whereas the AKhS occupies the area between the Khatanga and Anabar rivers (e.g. ...
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Anabar-Lena Composite Tectono-Sedimentary Element (AL CTSE) is located in the northern East Siberia extending for c. 700 km along the Laptev Sea coast between the Khatanga Bay and Lena River delta. AL CTSE consists of rocks from Mesoproterozoic to Late Cretaceous in age with total thickness reaching 14 km. It evolved through the following tectonic settings: (1) Meso-Early Neoproterozoic intracratonic basin, (2) Ediacaran - Early Devonian passive margin, (3) Middle Devonian - Early Carboniferous rift, (4) late Early Carboniferous - latest Jurassic passive margin, (5) Permian foreland basin, (6) Triassic to Jurassic continental platform basin and (7) latest Jurassic - earliest Late Cretaceous foreland basin. Proterozoic and lower-middle Paleozoic successions are composed mainly by carbonate rocks while siliciclastic rocks dominate upper Paleozoic and Mesozoic sections. Several petroleum systems are assumed in the AL CTSE. Permian source rocks and Triassic sandstone reservoirs are the most important play elements. Presence of several mature source rock units and abundant oil- and gas-shows (both in wells and in outcrops), including a giant Olenek Bitumen Field, suggest that further exploration in this area may result in economic discoveries.
... The Severnaya Zemlya Archipelago is located on the edge of the Kara Shelf, between the Kara and Laptev seas, and north of Taimyr; it includes four large islands (October Revolution, Bol'shevik, Komsomolets and Pioneer) and a small group of islands in the southwest, the Sedov Archipelago. Together with the northern part of the Taimyr Peninsula, Severnaya Zemlya represents the exposed part of the North Kara Plate (Bogdanov et al., 1998). Reconstruction of the Early Palaeozoic history of this region is controversial; some authors (e.g. ...
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The Furongian (Late Cambrian) Kurchavinskaya Formation of October Revolution Island, Severnaya Zemlya Archipelago, Arctic Russia, contains two distinctive morphotypes of the trace fossil Cruziana, both of which we assign to Cruziana semiplicata. A wider form shows characteristics typical of this ichnospecies with inner and outer lobes and marginal ledges. A narrow form has only an inner lobe with siculate, often interfering scratch-marks, and rare, narrow marginal ridges. This narrow form, which shows characters in common with Cruziana tortworthi, probably represents burrowing in a strongly head-down orientation. The record from October Revolution Island provides additional evidence that the palaeogeographical distribution of Cruziana semiplicata is not restricted to Gondwana, but also extend to parts of Baltica and North Kara. Cruziana semiplicata is known from the Furongian and Tremadocian of Gondwana, whereas on Baltica it is known only from the Furongian
... Within the Turukhansk area (often referred to as the Turukhansk Uplift), up to 4.5 km of Mesoproterozoic (?)-Neoproterozoic strata occur in three north-trending, faultbounded and east-transported blocks where the formations either dip gently westwards or occur in asymmetrical synclines with a gentle eastern limb and subvertical, partly truncated, western limbs (Petrov & Semikhatov 2001). These sandstones, shales, calcareous mudstones, dolostones, and limestones, including reef-bearing carbonate units were deposited on a passive continental margin (Petrov & Veis 1995;Petrov & Semikhatov 1997Sergeev et al. 1997;Bogdanov et al. 1998;Pisarevsky & Natapov 2003). The Turukhansk sediments include Neoproterozoic silicified microfossils and stromatolite assemblages (Petrov & Veis 1995;Sergeev et al. 1997;Knoll & Semikhatov 1998). ...
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