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1.
The Barents Sea shelf is an attractive target as a prospective large petroleum province. Further development of geological and geophysical exploration in the area requires high-resolution biostratigraphic constraints and update stratigraphic charts. The zonal succession of Lower and Middle Jurassic assemblages of foraminifers and ostracodes of the Barents Sea fits well the division for northern Siberia based on correlated independent Jurassic and Cretaceous zonal scales on all main microfossil groups, of which some scales were suggested as the Boreal Zonal Standard. The stratigraphic range of the Barents Sea microfossil assemblages has been updated through correlation with their counterparts from northern Siberia constrained by ammonite and bivalve data. Joint analysis of foraminiferal and ostracode biostratigraphy and lithostratigraphy of the sections allowed a revision to the stratigraphic position and extent of lithological and seismic units. The discovered similarity in the Lower and Middle Jurassic lithostratigraphy in the sections of the Barents Sea shelf and northern Siberia, along with their almost identical microfossil taxonomy, prompts similarity in the Early and Middle Jurassic deposition and geological histories of the two areas. 相似文献
2.
E. B. Pestchevitskaya 《Stratigraphy and Geological Correlation》2007,15(6):577-609
The described scheme of the Lower Cretaceous (Berriasian-Barremian) stratigraphic subdivisions is elaborated based on palynological study of sections in the Khatanga depression, Ust-Yenisei region, Pur-Taz interfluve, and around the Ob River latitudinal segment, the North Siberia. Stratigraphic distribution of microphytoplankton studied in detail is used to distinguish 10 biostratigraphic units in the rank of dinocysts zones. Stratigraphic position of the zones is determined with confidence using data on the Lower Cretaceous reference sections in the Khatanga depression, which were principal ones by constructing the Boreal standard zonation. In majority, boundaries of the dinocysts beds are of a high correlation potential and can be regarded as reliable stratigraphic markers, as they are recognizable not only in Siberia, but also in northern Europe and America. 相似文献
3.
V. G. Knyazev R. V. Kutygin S. V. Meledina 《Stratigraphy and Geological Correlation》2009,17(2):192-203
Modifications to the upper Bathonian zonal scale for northern East Siberia provided by the newly available paleontological record on Middle Jurassic reference sections in the Arctic regions of Yakutia and by the revised earlier collections, are justified. The oldest East Siberian members of Cadoceras are found to be characteristic not of the initial Callovian age as believed by Russian paleontologists, but of the terminal Bathonian age as was previously shown in the biostratigraphic scheme of East Greenland. The succession of zones and index species analogous to that of the latter is revealed in the studied region and the zonal boundaries in Siberia and East Greenland are inferred to be synchronous. Finds of Cadoceras calyx in the upper Bathonian scale permitted, for the first time, the recognition of a corresponding zone. The Bathonian-Callovian boundary is placed between the calyx and anabarense zones. The upper Bathonian zonal scale of northern East Siberia is now in total agreement with the East Greenland zonal scale. 相似文献
4.
N. K. Mogucheva 《Stratigraphy and Geological Correlation》2016,24(3):252-266
The first data on the taxonomic composition of the Induan flora of Siberia are presented. The investigation of Triassic reference sections in northern Siberia (eastern Taimyr, Lena–Anabar Trough, Verkhoyansk region) and correlation with volcano-sedimentary complexes of the Tungus and Kuznetsk basins made it possible to establish for the first time the taxonomic composition of the flora from the Induan Stage of Siberia. Its composition is heterogeneous, forming two large plant formations, which occupied different ecological niches. On the eastern coastal-marine margins of Siberia (eastern Taimyr, Olenek coast, Verkhoyansk region), the Induan flora was largely characterized by lepidophytic (Tomiostrobus) plants, while in the intracontinental areas (Tungus and Kuznetsk basins, partly Verkhoyansk region), it was characterized by Equisetales–Filicales communities. 相似文献
5.
B.L. Nikitenko V.G. Knyazev N.K. Lebedeva E.B. Peshchevitskaya R.V. Kutygin 《Russian Geology and Geophysics》2011,52(9):963-978
The Oxfordian–Lower Hauterivian section of the Nordvik Peninsula (northern Central Siberia) is a reference for developing zonal scales for various fossil groups and improving the Boreal zonal standard. In the middle 1950s–late 1980s, it was studied extensively by geologists, stratigraphers, lithologists, and experts on various fossil groups. These studies yielded rich fossil and microfossil collections and a set of parallel zonal scales for various faunal groups. Recently, a new detailed ammonite zonation of the Oxfordian and Kimmeridgian units of this section has been proposed. These results contradict the previous biostratigraphic data on ammonites, foraminifers, and palynomorphs. In the present paper, all the biostratigraphic data on the Oxfordian and Kimmeridgian units of the Nordvik Peninsula (Cape Urdyuk-Khaya) and northern Central Siberia undergo a comprehensive analysis and comparison with those on the Boreal Realm. The ammonite-constrained stratigraphic position of the lower Upper Jurassic in the Cape Urdyuk-Khaya section is interpreted as Upper Oxfordian or Middle Oxfordian. In our view, this difference in the understanding is due to the misidentification of some Oxfordian ammonite forms. The zones based on other fossil groups (foraminifers, dinocysts) which were distinguished in the Upper Oxfordian and Kimmeridgian sections of the Nordvik Peninsula are well traceable circumarctically. Their stratigraphic position in various regions of the Northern Hemisphere is constrained by ammonites and bivalves. However, if we use the last alternative ammonite zonation of this section part, hardly explicable contradictions will appear in interregional foraminiferal and dinocyst correlations. 相似文献
6.
Integrated chronostratigraphy of Proterozoic-Cambrian boundary beds in the western Anabar region, northern Siberia 总被引：2，自引：0，他引：2
Kaufman AJ Knoll AH Semikhatov MA Grotzinger JP Jacobsen SB Adams W 《Geological magazine》1996,133(5):509-533
Carbonate-rich sedimentary rocks of the western Anabar region, northern Siberia, preserve an exceptional record of evolutionary and biogeochemical events near the Proterozoic/Cambrian boundary. Sedimentologically, the boundary succession can be divided into three sequences representing successive episodes of late transgressive to early highstand deposition; four parasequences are recognized in the sequence corresponding lithostratigraphically to the Manykal Formation. Small shelly fossils are abundant and include many taxa that also occur in standard sections of southeastern Siberia. Despite this coincidence of faunal elements, biostratigraphic correlations between the two regions have been controversial because numerous species that first appear at or immediately above the basal Tommotian boundary in southeastern sections have first appearances scattered through more than thirty metres of section in the western Anabar. Carbon- and Sr-isotopic data on petrographically and geochemically screened samples collected at one- to two-metre intervals in a section along the Kotuikan River, favour correlation of the Staraya Reckha Formation and most of the overlying Manykai Formation with sub-Tommotian carbonates in southeastern Siberia. In contrast, isotopic data suggest that the uppermost Manykai Formation and the basal 26 m of the unconformably overlying Medvezhya Formation may have no equivalent in the southeast; they appear to provide a sedimentary and palaeontological record of an evolutionarily significant time interval represented in southeastern Siberia only by the sub-Tommotian unconformity. Correlations with radiometrically dated horizons in the Olenek and Kharaulakh regions of northern Siberia suggest that this interval lasted approximately three to six million years, during which essentially all 'basal Tommotian' small shelly fossils evolved. 相似文献
7.
Seismic and geological information on the Lomonosov Ridge is considered with reference to drilling data obtained during the ACEX-302 expedition. A new zonation proposed for the composite section of the ridge sedimentary cover and based on marine microfossils (silicoflagellates and dinocysts) from several boreholes is correlated with biostratigraphic zones of Paleogene sections in northern West Siberia. Principal stages of the Arctic basin development in the Aptian-Cenozoic are defined in onshore and Lomonosov Ridge sections. Synchronous formation of sedimentary sequences in the ridge, an element of the Arctic basin, shelves, and epicontinental seas is established for the period under consideration. 相似文献
8.
分析了西西伯利亚东南地区的下凡兰吟阶的两个剖面的陆相孢粉型化石的分布。依据西伯利亚北部已经定年的剖面中动物群建立起来的孢粉组合的对比,确定了孢粉标志层的定义,并与北方区的菊石带相对应的孢粉组合进行了对比。这一工作为早凡兰吟期与气候变化息息相关的植被和景观的短期变化以及周边古盆地变迁的重建,提供了地层依据。欧亚大陆中部和东部地区凡兰吟期孢粉组合的横向对比显示:西西伯利亚东南地区的植被具有印度欧洲和西伯利亚加拿大两大古植物地理区的过渡性质,显有这两区的典型特征。 相似文献
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10.
Primitive ceratopian dinosaurs of the family Psittacosauridae were hitherto known only from central and northern Asia, from northern China to Mongolia and Siberia. This paper reports the discovery of psittacosaurid jaws in Early Cretaceous rocks of the Khorat Plateau in north-eastern Thailand. These fossils are clearly referrable to the genus Psittacosaurus Osborn and may represent a new species. They constitute a significant new element of the hitherto poorly known Cretaceous continental vertebrate fauna of South-East Asia, suggesting that it was basically similar to that of northern and central Asia. This in turn confirms that, contrary to some recent palaeogeographical reconstructions, by Early Cretaceous times the Indochina block, on which the Thai psittacosaurids have been found, had become part of mainland Asia. 相似文献
11.
Siberia and Rodinia 总被引：2，自引：0，他引：2
An analysis of the Riphean sedimentary successions along the margins of the Siberian craton, together with recent geochronological and palaeomagnetic data from Siberia, require a revision of the hypothesis that Siberia was part of Rodinia. Some previously proposed Laurentia–Siberia reconstructions may be dismissed, whereas other models are permissible with minor modifications and conservative assumptions about recent geochronological data from Siberia. A comparison of Laurentian and Siberian apparent polar wander paths between 1050 and 1000 Ma shows a striking similarity. However, if Siberia was part of Rodinia, it was probably not contiguous with the Laurentian craton. In this scenario, northern and southern (Stanovoy block) margins of Siberia are possible candidates for conjunction with the rest of Rodinia. We propose a new reconstruction of Laurentia and Siberia at ca. 1050–1000 Ma. 相似文献
12.
T. A. Ivanovskaya 《Lithology and Mineral Resources》2009,44(4):348-366
Structure of the lower subformation of the Khaipakh Formation from the upper portion of the Middle Riphean Olenek Uplift (northern Siberia) is considered. It has been noted for the first time that the glauconite-containing sandy-aleurolitic rocks (hereafter, sandstones and siltstones) in sections of the Khorbusuonka River include glauconitite laminas and siderite lenses that are distinct marker horizons of this stratigraphic interval. It has been shown that the glauconitites are weakly cemented and almost completely composed of glauconite grains and glauconite cement. The paper presents detailed mineralogical and structural-crystallochemical characteristics of Al-glauconite in specimens with different degrees of cementation (solid and loose rocks). The paper discusses genetic features of glauconite grains and their secondary alterations. Comparative characteristics of glauconite from solid and loose rocks from both Khaipakh sections and previously studied terrigenous rocks of the Arymas and Totta formations (Middle Riphean Olenek Uplift and Uchur-Maya region) are given. Suitability of glauconite extracted from the glauconitites for isotope-geochronological investigations is estimated. Literature and original data on glauconitites formed in situ in Precambrian and Phanerozoic sections are compared. It is concluded that their primary macroscopic and microscopic features are very similar. 相似文献
13.
V.Yu. Bragin O.S. Dzyuba A.Yu. Kazansky B.N. Shurygin 《Russian Geology and Geophysics》2013,54(3):335-348
The results of this study were used to identify a reversed polarity magnetozone, referred to as M17r, in Berriasian sections of the Nordvik Peninsula (northern East Siberia) within the normal polarity magnetozone (M18n) from previous studies. The new magnetozone embraces the Volgian–Ryazanian boundary (Chetaites chetae/C. sibiricus zonal boundary). It was also found that the former magnetozone M17r at Nordvik, which includes the C. sibiricus/Hectoroceras kochi zonal boundary should correspond to magnetozone M16r. Using magnetostratigraphic and biostratigraphic criteria proves that the Boreal C. sibiricus Zone is correlated with at least the major part of the Tethyan Tirnovella occitanica Zone, and the Boreal H. kochi Zone is correlated with the lower part of the Malbosiceras paramimounum Subzone of the Tethyan Fauriella boissieri Zone. 相似文献
14.
15.
Global climate change at the end of Pleistocene led to extinction in the huge territories of Northern Eurasia of the typical representatives of the Mammoth fauna: mammoth, woolly rhinoceros, wild horse, bison, musk-ox, and cave lion. Undoubtedly the Mammoth fauna underwent pressure from Upper Paleolithic humans, whose hunting activity could also have played a role in decreasing the number of mammoths and other representatives of megafauna. Formerly it was supposed that the megafauna of the “Mammoth complex” had become extinct by the beginning of the Holocene. Nevertheless the latest data indicate that extinction of the Mammoth fauna was significantly delayed in the north of Eastern Siberia. In the 1990s some radiocarbon dates established that mammoths existed in the Holocene on Wrangel Island—from 7700 until 3700 yBP. Radiocarbon data show that wild horses inhabited the north of Eastern Siberia 4600–2000 yBP. Muskoxen lived here about 3000 yBP. Some bison remains from Eastern Siberia belong to the Holocene. The following circumstances could promote the survival of representatives of Mammoth fauna. Cool and dry climate in this region promotes the maintenance of steppe associations—the habitats of those mammals. Late Paleolithic and Mesolithic settlements are not found in the Arctic zone of Eastern Siberia from Taimyr Peninsula to the lower Yana River; they are very rare in basins of the Indigirka and Kolyma Rivers. The small number of Stone Age hunting tribes in the northern part of Eastern Siberia was probably another factor that contributed to the survival of some Mammoth fauna representatives. 相似文献
16.
新疆北部及邻区地质构造单元与地质发展史 总被引：22，自引：5，他引：22
新疆北部及邻区在区域构造上分属西伯利亚、哈萨克斯坦—准噶尔及塔里木三大板块，它们被两条时代不同（石炭—二叠纪、志留—泥盆纪）、规模宏伟的板块缝合构造带所分隔，缝合构造带与两侧板块有着密切的亲缘关系，却无隶属的“父子”关系，三大板块自元古宙发生解体裂移后，增生作用主要发生在早古生代，主要是依据各陆缘的不同特征分别形成岛弧或边缘海盆；进入晚古生代后，哈萨克斯坦—准噶尔板块与培里木板块已率先完成碰撞缝合，此时除斋桑—额尔齐斯—线尚有古亚洲洋残余外，绝大部分地区均进入陆内构造发展阶段，其主要构造活动是“手风琴式’的开合构造，形成一些裂陷槽、裂谷和上叠盆地。研究区内共分出１５个二级构造单元和４４个三级单元。 相似文献
17.
《Russian Geology and Geophysics》2014,55(10):1205-1218
The Oxfordian Stage of West Siberia contains Boreal ammonites Cardioceratidae. The authors’ bank of paleontological data includes ~ 500 definitions of Cardioceratinae, permitting a considerable refinement of the official Oxfordian regional zonal scale. The lower substage is divided into the Cardioceras (Scarburgiceras) obliteratum, C. (S.) scarburgense, and C. (S.) gloriosum Zones instead of beds with C. (S.) spp., whereas the C. (Cardioceras) percaelatum and C. (C.) cordatum Zones are recognized instead of beds with C. (C.) spp. We have found new ammonites typical of the Middle Oxfordian C. (Subvertebriceras) densiplicatum and C. (Miticardioceras) tenuiserratum Zones. The first of these zones is divided into two subzones. The Upper Oxfordian includes the Amoeboceras glosense and A. serratum Zones instead of beds with A. spp., and the A. regulare Zone and beds with A. rosenkrantzi are recognized instead of the A. ex gr. regulare Zone. The genus Ringsteadia (Aulacostephanidae) is observed only in the northwestern part of the region, along the eastern slope of the North Urals; therefore, two upper units of the biostratigraphic scale correspond to beds with Ringsteadia marstonensis.In the Oxfordian, West Siberia and northern Siberia belonged to the North Siberian province of the Arctic realm. Only in the latest Oxfordian did the northwestern West Siberian basin become part of the Boreal-Atlantic realm, as evidenced by the distribution of Ringsteadia on the eastern slope of the Cis-Polar Urals. 相似文献
18.
新疆北部古生代构造演化的几点认识 总被引：23，自引：12，他引：11
最近的地质调查和研究资料揭示,新疆北部古生代存在"三块两带"的构造格局,并经历了复杂的洋陆转换过程。地质、地球物理和碎屑锆石年龄结果显示,准噶尔盆地南部应存在一个至少发育前震旦系的古老陆块;初步认为东准噶尔北自额尔齐斯构造带东南的玛依鄂博地区至南部的卡拉麦里构造带南界,整体为一增生杂岩体,西准噶尔自额尔齐斯构造带南缘至谢米斯台南缘亦为一增生杂岩体。提出新疆北部加里东运动表现为准噶尔-吐哈陆块、中天山陆块群、伊犁地块等拼合形成哈萨克斯坦板块的一部分。从新疆北部泥盆系建造组合和沉积环境演变视角,探讨了早古生代形成的哈萨克板块北部洋盆从早泥盆世开始,至晚泥盆世拼合,洋盆经历了逐渐变浅直至消亡的演化过程。结合区域地质调查资料,提出南天山为一巨大的增生杂岩体,代表了哈萨克斯坦板块与塔里木板块最后增生拼合的位置,亦是古亚洲洋在中国境内最后闭合的位置,闭合的时限为早石炭末期。在以上认识的基础上,提出新疆北部晚古生代构造演化的"三块两带"基本框架:即在统一哈萨克斯坦板块形成后,自北而南依次存在西伯利亚板块、哈萨克斯坦板块、塔里木板块及其间的准噶尔洋盆和南天山洋盆。晚泥盆世哈萨克斯坦板块与西伯利亚板块完成增生拼贴;早石炭世末,塔里木板块与西伯利亚-哈萨克斯坦联合板块完成增生拼贴,古亚洲洋结束洋陆转换;晚石炭世至早二叠世,新疆北部进入后碰撞伸展至大陆裂谷演化阶段。 相似文献
19.
B.L. Nikitenko B.N. Shurygin V.G. Knyazev S.V. Meledina O.S. Dzyuba N.K. Lebedeva E.B. Peshchevitskaya L.A. Glinskikh A.A. Goryacheva S.N. Khafaeva 《Russian Geology and Geophysics》2013,54(8):808-837
Recent integrated studies of Mesozoic reference sections of the Anabar area (northern Middle Siberia, Laptev Sea coast) and the reinterpretation of all the previous data on a modern stratigraphic basis permit considerable improvement of the bio- and lithostratigraphic division and facies zoning of Jurassic and Cretaceous sediments in the region. Analysis of abundant paleontological data allows the development or considerable improvement of zonal scales for ammonites, belemnites, bivalves, foraminifers, ostracods, dinocysts, and terrestrial palynomorphs from several Jurassic and Cretaceous intervals. All the zonal scales have been calibrated against one another and against regional ammonite scale. Reference levels of different scales useful for interregional correlation have been defined and substantiated based on the analysis of lateral distribution of fossils in different regions of the Northern Hemisphere. It provides the possibilities to propose and consider parallel zonal scales within the Boreal zonal standard for the Jurassic and Cretaceous periods. A combination of these scales forms an integrated biostratigraphic basis for a detailed division of Boreal-type sediments regardless of the place of their formation and for the comparison with the international stratigraphic standard as far as a possible use of a set of reference levels for correlation. 相似文献
20.
根据区域构造、古地理和地层资料,中国奥陶纪的诸多板块、地体和活动带应分属11个地理区。文章重点研究了各地理区的边界。这些相邻的地理区块在奥陶纪曾处于远距离分离状态,除华北区南界和华南区北界明显由同期秦岭活动带限定之外,地理区的界线大多只能沿发生在奥陶纪之后的构造拼贴结合带划定,只有塔里木区北界和北疆区南界,得以通过追索代表曾在奥陶纪时段内发育于塔里木板块/哈萨克斯坦中间板块/西伯利亚板块之间的局限洋盆或深海盆地遗迹（即残留缝合带）来予以确定。中国大陆的最终形成经历了从晚石炭世至新生代的长期地质演化过程,主要包括活动带的消减以及板块和地体的漂移、增生与会聚。 相似文献