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1
Content available remote Ruchy separatystyczne w Federacji Rosyjskiej
PL
Artykuł zawiera ocenę polityki wewnętrznej Kremla wobec separatystycznych dążeń republik federacyjnych. Dynamika zmian na arenie międzynarodowej, sankcje ekonomiczne nałożone na Federację przez Unię Europejską oraz rosyjsko-ukraiński konflikt spowodowały, że polityka polegająca na ukrywaniu tendencji separatystycznych republik stanowi dla władz rosyjskich coraz większy problem. Dotychczas znane ruchy niepodległościowe uległy znacznej radykalizacji, a dążenia Czeczenii, Inguszetii i Dagestanu do uzyskania niepodległości lub pogłębienia autonomicznych praw zastąpiła wizja powołania teokratycznego, islamskiego państwa – Emiratu Kaukaskiego. Wspieranie przez władze rosyjskie separacji Krymu i wschodniej Ukrainy obudziły również uśpione żądania mieszkańców Syberii, żądających oderwania jej od Rosji. W obecnej sytuacji wyciszenie oraz kontrolowanie stopnia przepływu informacji o zrywach separatystycznych Kaukazu Północnego i Syberii należy postrzegać jako jedno ze zjawisk o szczególnie wysokim priorytecie dla Federacji Rosyjskiej.
EN
The article contains the assessment of the Kremlin’ domestic policy towards separatist aspirations of federal republics. The dynamics of changes on the international arena, economic sanctions imposed on the Federation by the European Union along with Russian-Ukrainian conflict caused that the policy of hiding separatist tendencies of some republics has become a growing problem for the Russian authorities. Independence movements known so far, have become more radical, while determination of Chechnya, Ingushetia and Dagestan to gain independence or to deepen their autonomous rights have been replaced by a vision of creating a theocratic, Islamic state – the Caucasus Emirate. Support offered by the Russian authorities to the Crimean and eastern Ukraine separatists, awakened the latent aspirations of the Siberian population to become detached from Russia. In the present situation, muting and taking under control the flow of information on separatist uprisings in the North Caucasus and Siberia should be perceived as high priority phenomena for the Russian Federation authorities.
PL
Ignacy Sobieszczański (1872-1952), inżynier, absolwent Instytutu Inżynierii Komunikacji w Petersburgu. W tartach 1905 –1920 ściśle związany z Syberią. Poszukiwacz złota, węgla, miedzi, żelaza, wolframu, azbestu…Bogacz węglowy. Wybitny działacz przemysłowo-handlowy. W czasie I wojny światowej współorganizator Polonii Syberyjskiej i jej narodowych, opiniotwórczych Zjazdów w Harbinie(Mandżuria). Finansowy opiekun polskich jednostek wojskowych na Syberii. Organizator powrotu Sybiraków do kraju. W Odrodzonej Polsce współorganizator struktur przemysłowo-handlowych w Poznaniu, Szczecinie, Warszawie.
EN
Ignacy Sobieszański (1872-1952) was an engineer, graduate of the Engineering Institute of Road Communications in Sankt Peterburg. From 1905 to 1920 he was closely connected with Siberia as a prospector of gold coal, copper, iron, wolfram, asbestos and others minerals. He grew wealthy through coal. He was an eminent industry and trade activist. During the First World War he co-organized the Polish community in Siberia and their national opinion-forming conventions in Harbin, Manchuria. He supported financially Polish army units in Siberia and organized return of Siberian deportees to homeland. After the rebirth of Poland he contributed to industrial and trade structures in Poznań, Szczecin and Warsaw.
3
Content available remote Polska polityka surowcowa za granicą
EN
The Polish expansion in mineral exploration is going to start with Africa. This is expressed in Government documents. Such direction is obviously welcome, but is not the most important. Chinese competitiveness in that continent is insurmountable. The Polish science was most successful in this field in the 19th and early 20th centuries in Siberia. Its achievements have been appreciated there until today, independently of political turmoil in Polish-Russian relations. This direction of the policy in mineral exploration is the most promising because this is where the world economy and policies are currently targeted. A weakness of both these options is the lack of commonly available knowledge about both Africa and Siberia, and about other areas of our interests in raw materials around the world. This should be a starting point to a debate about the Polish policy in mineral exploration abroad.
RU
Объектом исследования являются породы фундамента и нижней части осадочного чехла западной части Западно-Сибирской платформы. Данная область имеет сложное геологическое строение и до настоящего времени недостаточно изучена. В пределах этой территории уже успешно добывается нефть из пород фундамента на ряде месторождений. Следовательно, рассматриваемый участок может быть перспективным в этом отношении. Целью работы стало исследование пород фундамента и выявление перспективных зон образования коллекторов нефти и газа. Исследования проводились по шламу, отобранному с интервалом 5÷20 м с глубин 1060÷1350 м в процессе бурения 5 скважин. Образцы изучались макроскопически, в стереомикроскопе и в петрографических шлифах. В результате исследований выделены и охарактеризованы литотипы пород осадочного чехла и петротипы доюрского основания. Основное внимание уделялось породам фундамента, в составе которого выделены: долериты, лейкодолериты, габбро, конга-диабазы, лейкоконга-диабазы и гранодиориты. Вулканические породы относятся вероятно к базальт-долеритовой и липарит-лейкобазальтовой формации перми-триаса, габброиды слагают небольшие гипабиссальные интрузии более позднего возраста. В породах фундамента присутствует большое количество трещин, заполненных гидротермальными минералами. Это говорит о сильных тектонических напряжениях и дислокациях, а также о гидротермальных процессах, последняя активизация которых, вероятно, происходила после формирования осадочного чехла. В целом отмечается невысокая интенсивность развития процессов выветривания и, по-видимому, небольшая мощность кор выветривания в которых можно ожидать формирование поровых коллекторов. Наиболее вероятно развитие пористости в гранитоидах и конга-диабазах, поскольку в них отмечаются единичные пустоты выщелачивания. Во всех породах присутствуют тонкие трещины. Они либо открытые, либо заполнены вторичными минералами – альбитом, эпидотом, кальцитом.
EN
The basement rocks and the lower sedimentary unit of the west part of West Siberian plate are the subject of the study. This region has complex geological setting and is still understudied. Several fields show successful oil exploitation from basement in the area. This fact is the basis to consider the study area to be perspective for hydrocarbon exploration. The aim of the study is concerned with the basement rock identification and detection of perspective reservoir zones. The data for study was presented by rock cuttings from 5 wells obtained with interval 5÷20 m from depths of 1060÷1350 m. These samples were investigated using stereoscope for cuttings and using microscope for thin sections. The features of sedimentary rock lithotypes and basement rock petrotypes were described during the study. The main attention is paid to the basement rocks: dolerites, leucodolerites, gabbro, conga-diabases, leucoconga-diabases and granodiorites. The volcanic rocks seem to be associated with the basalt-dolerite and liparit-leikobasalt formations (Permian-Triassic), the gabbroids relate to small intrusions of younger age. A lot of cavities filled with hydrothermal minerals are discovered in the basement rocks. This fact indicates a strong tectonic influence on these rocks, with the last activation being supposed to occur after the formation of lower sedimentary unit. The study area shows low degree of weathering, so small thickness of weathering crust with porous reservoirs can be expected. The porosity is most probable to be in the granitic rocks and in conga-diabases as singular micro-caverns are discovered in these rocks. Thin fractures are detected in all rock types. Fractures are found to be open or filled by albite, epidote and calcite secondary minerals.
RU
Активное внедрение пластовых вод, выпадение больших объемов конденсационных вод в пласте при разработке месторождений углеводородов (УВ) не только снижает эффективность добычи УВ, но и способствует геохимическому поражению пород коллекторов. Идея прогнозирования масштабов и времени обводнения нефтегазопромысловых объектов по изменению химического состава попутных вод не нова. На некоторых промыслах такой анализ проводится на постоянной основе, однако этот метод мониторинга эксплуатации месторождений УВ, несомненно, заслуживает более широкого внедрения в силу того, что он является весьма информативным, экономически выгодным и простым в исполнении. В данной работе анализируется результативность гидрохимических исследований при разработке месторождений УВ. Рассматриваются особенности диагностики вод различного генезиса в условиях низкоминерализованных пластовых вод. Предлагаются критерии определения доли конденсационных, технических и пластовых вод в составе попутных флюидов даже в условиях равенства минерализации вод различного генезиса. Рассматриваются вопросы взаимодействия конденсационных вод в минералообразующими компонентами коллекторов. На примере газовых месторождений Западной Сибири показаны возможности ранней диагностики притока пластовой воды, а также анализа качества ремонта эксплуатационных скважин.
EN
Active formation water intrusion and loss of large amounts of condensate water in reservoir not only reduces the hydrocarbons (HC) recovery efficiency but also contributes to reservoir rock’s geochemical defeat during HC development. Forecasting idea of scale and water encroachment time of oil-and-gas production facilities on the chemical composition change of formation water is not new. Such analysis is carried out on a constant basis on-site. However this monitoring method of HC field exploitation deserves a wider implementation inasmuch as it is very informative, cost-effective and easy to implement. In this article an efficiency of the hydro-chemical researches is analyzed during HC field’s exploration. The features of the different genesis waters diagnostic in conditions of low-mineralized formation waters are considered. The quantity criteria of condensate technical and formation waters in the formation fluid composition even in conditions of different genesis water mineralization are proposed. The questions of the condensate waters interaction with mineral-formation reservoir rock’s components are considered. As exemplified by the West Siberia gas fields the possibility of early diagnostic of the formation waters inflow are showed as well as the quality of well repair work analysis.
EN
The purpose of this publication is to present Agaton Giller as a Zabajkale Region researcher. Earlier works devoted to him related primarily to his political activity during the 1863 uprising and his journalism in exile. In this paper special emphasis is put on geographical explorations and Giller’s observation touring, which are reflected in his writings from the period of his stay in Eastern Siberia. In addition, an attempt was made to locate Description of the Zabajkale Region against a background of contemporary geographical literature. Agaton Giller lived in Siberia from 1854 to 1860. He had been sent there by the tsarist authorities for illegal attempt to cross the border. Being formally a soldier, he was allowed to travel to Zabajkale. His trips served him as a source of environmental knowledge about the region. He also conducted meteorological and ornithological observations and watched the local flora and fauna. His additional source of information about Zabajkale was scientific literature. Giller benefited from articles published in a newspaper by a local geographical society. However, there were very few of them at that time. In the 19th century, geography emerged as a separate academic discipline and there were first departments of geography created at universities. Gradually, within the scope of geographical research, physical geography was emerging. Until mid-19th century, the topics in this field were dealt with mainly by geologists and naturalists. Much faster human geography was developed based on the study of transformations of settlement, economic development, transportation and communication. Three research areas were singled out: descriptions of travel, descriptions of economy and statistical descriptions of the region. The term “statistics” of the time related to records of natural resources and economic area. It often also contained information concerning biology, population, ethnography, economy and history. This way of description of geographic space influenced publications themselves: they were often a collection of dry facts and statements. Referring to the major nineteenth-century conventions in description of natural environment, Description of the Zabajkale Region can be classified as a statistical and economical one. This is due to the fact that the Giller listed a number of facts and information but did not try to analyze them in depth. He was not looking for complex cause-effect relationship, nor he attempted to explain the relationship between the individual components of the environment. The elements characteristic for propagated by Karl Ritter convention of regional description appeared only in the analysis of the impact of selected environmental factors on people’s lives. It can be assumed that this was not done on purpose. This information was placed by Giller quite randomly in different parts of the text and tend to refer rather to the ways of coping in extreme conditions. To sum up, it can be stated that Description of the Zabajkale Region is not a scientific monograph of the region. It omitted many important natural issues and developed marginal ones, concerning e.g. buddhism, or the history of Genghis Khan. This may be due to the fact that Giller did not have factual knowledge: he did not graduate from a university and did not receive proper education. However, it is still an interesting example of a study conducted by a Polish exile.
EN
Marine carbonates and siliciclastic rocks of the Burj Formation in Jordan include paucispecific trilobite associations of the (traditional) Lower. Middle Cambrian boundary interval. Comprehensive new material of these trilobites allows a review of their taxonomy and systematic positions as well as a refined morphological description and a reconsideration of previous interpretations of their stratigraphic position and thus the correlation of the fossiliferous beds. In addition to the classic species Kingaspis campbelli (King, 1923) and Redlichops blanckenhorni Richter and Richter, 1941, Timnaella? orientalis (Picard, 1942) and Hesa problematica Richter and Richter, 1941, the discussed trilobites include Issalia gen. nov. with Issalia scutalis gen. nov., sp. nov., Tayanaspis gen. nov. with Tayanaspis bulbosus gen. nov., sp. nov., Uhaymiria gen. nov. with Uhaymiria glabra gen. nov., sp. nov., Cambrunicornia? jafnaensis sp. nov., Myopsolenites palmeri (Parnes, 1971), M. hyperion sp. nov., and Enixus cf. antiquus (Chernysheva, 1956). Myopsolenites boutiouiti Geyer and Landing, 2004 is now regarded as a junior synonym of Myopsolenites altus (Lian and Gozalo, 1986). A detailed discussion of the correlation with a focus on global aspects provides clues for the utility of potential index fossils for the global Cambrian Series 3 and Stage 5.
9
PL
Konsekwencją budowy zbiorników wodnych jest tworzenie się pokrywy osadów dennych. Osady często są postrzegane jako środowisko akumulacji substancji chemicznych, w tym zwłaszcza związków fosforu oraz wielu mikrozanieczyszczeń. Badaniom chemicznym poddano osady denne Zbiornika Irkuckiego. Jest to najwyższy zbiornik kaskady rzeki Angary, zasilany głównie wodami wypływającymi z jeziora Bajkał. Badania prowadzono w lipcu 2010 roku w rejonie miejscowości Nowogrudinina i Patrony. W składzie podstawowym osadów dominował ditlenek krzemu (SiO2) - 56,75÷61,24%. Znacząca była też zawartość Al2O3 14,12÷15,79% oraz Fe2O3 6,04÷7,17%. Pięciotlenek fosforu (P2O5) występował w ilości 0,17÷0,24%. Wśród pierwiastków śladowych największym udziałem w materiale osadowym wyróżniały się: bar 582÷615 ppm, cyrkon 200÷863 ppm, stront 186÷274 ppm, chrom 147÷243 ppm, wanad 123÷140 ppm, cer 85÷151 ppm i cynk 73÷94 ppm. Na ogół zawartości pierwiastków śladowych w osadach nie przekraczały naturalnych zawartości w skałach i glebach. Tylko nieliczne pierwiastki, np. chrom, występowały w ilościach większych niż tło geochemiczne.
EN
Construction of water reservoirs results in formation of a layer of bottom sediments. Sediments are often perceived as the environment of accumulation of chemical substances, particularly including phosphorus compounds and numerous microcontaminants. The chemical studies concerned bottom sediments of Irkutsk Reservoir, which is the highest reservoir in the Angara river cascade, mainly fed by water flowing out of Lake Baikal. The studies were carried out in July 2010 near towns of Novogrudinina and Patrony. The main composition of the sediments was dominated by silicon dioxide (SiO2) - 56.75÷61.24%. Concentrations of Al2O3 and Fe2O3 were also significant, 14.12÷15.79% and 6.04÷7.17% respectively. Phosphorus oxide (P2O5) concentration was 0.17÷0.24%. The largest concentrations of trace elements in the sediments were those of: barium 582÷615 ppm, zirconium 200÷863 ppm, strontium 186÷274 ppm, chromium 147÷243 ppm, vanadium 123÷140 ppm, cerium 85÷151 ppm, and zinc 73÷94 ppm. Generally, concentrations of trace elements in the sediments did not exceed natural concentrations in rocks and soils. Only some elements, eg chromium, occurred in higher concentrations than the geochemical background.
EN
То improve the efficiency of squeeze jobs using selective compounds on the basis of waterless cement slurry (WCS) there was developed the соmрlеx technology of selective water shut-off in which а selective composition — hydrocarbon solution of а water-repellent surfactant and (or) inverse emulsion based on it — is injected before the WSC, depending on the well injectivity. In the process of injection waterproofing composition occurs the destruction of the water fi1m, squeezing out water from the bottom zone. The hydrophobic agent is attached to the rock surface, preventing its resaturation. High selective and isolating properties of the given соmрlех technology of selective water shut-off by the ехаmрlе of the oilfields of the Western Siberia and Turkmenistan are confirmed.
PL
Elektrownia wodna Sajano-Szuszenskaja jest położona na syberyjskiej rzece Jenisej w pobliżu Sajanogorska. Jest to największa elektrownia wodna w Rosji i szósta co do wielkości elektrownia wodna na świecie. Wytwarza ponad jedną czwartą energii elektrycznej produkowanej przez rosyjskie elektrownie wodne. Decyzja o jej budowie zapadła w 1960 roku. Geologowie wybrali dokładne miejsce pod jej budowę w 1961 roku. Budowa ruszyła w 1968 roku, a jej otwarcie nastapiło w 1978 roku. Elektrownia jest zarządzana przez przedsiębiorstwo RusHydro. Wyposażono ją w 10 hydrogeneratorów o mocy 640 MW każdy.
PL
Systematyczne badania obszarów Syberii i Dalekiego Wschodu rozpoczęły się z początkiem XIX wieku. Znaczący udział w tych badaniach mieli Polacy. Byli to zarówno zesłańcy, którzy trafili tam po upadku kolejnych powstań, jak i podróżnicy, badacze i przemysłowcy, których przyroda lub chęć zysku ciągnęły w tamte strony. Wśród nich było wielu geologów. Wachlarz ich zainteresowań był bardzo szeroki i obejmował również etnografię, zoologię, botanikę. Wykonywali oni również pomiary meteorologiczne i topograficzne. W artykule przedstawiono sylwetki słynnych geologów: Aleksandra Czekanowskiego, Jana Czerskiego, Karola Bohdanowicza, Józefa Morozewicza oraz mniej znanych – Antoniego Giedroycia, Leona Barszczewskiego, Bronisława Grąbczewskiego, Leonarda Jaczewskiego, Kazimierza Grochowskiego i Stanisława Doktorowicza-Hrebnickiego. Wszyscy byli znakomitymi badaczami i zapisali się złotymi zgłoskami w poznanie obszarów położonych na wschód od Uralu. Część z nich, po odzyskaniu niepodległości wniosła doniosły wkład w rozwój nauk geologicznych w Polsce.
EN
Systematical studies of Siberia and the Far East regions were started in the beginning of XIX century. Poles participated significantly in those studies. There were deportees after overthrowing of the following insurrections and also voyagers, explorers and industrialists – all of whom were attracted to that region by nature and cupidity. There were a lot of geologists among those people. Their interests ranged from ethnography, zoology to botany. They also carried on meteorological and topographical measurements. In the present paper, there are outlines of such well-known explorers as: Aleksander Czekanowski, Jan Czerski, Karol Bohdanowicz or Józef Morozewicz and, less famous, Antoni Giedroyć, Leonard Barszczewski, Bronislaw Grąbczewski, Leon Jaczewski, Kazimierz Grochowski, Stanisław Doktorowicz-Hrebnicki portrayed. All of them were brilliant researchers, they distinguished themselves in exploration territories east of Ural. After recovery of independence, part of them contributed significant share in developing of geological sciences in Poland.
EN
At the moment of establishing of 5th Division of Polish Riflemen Colonel Rumsza was nominated as a commander who was subordinated to - promoted twice in short time by general Haller - lieutenant colonel Czuma, commander of Polish army in Siberia. In the first months of 1919, personnel for the division reached 770 officers and more than 10,000 soldiers. The first half of 1919 was the period of relative peace. Yet the failures of Admiral Aleksander Kołczak (he called himself "all Russian governor" on 1st December 1918, after overthrowing the existing counter-revolutionary authorities,) on wide front of civil fights, started to engage Polish troops in fights with Bolsheviks. Despite making an agreement on military cooperation with countries of the Coalition, between counter-revolutionary Russian units, expedition army of Entente and national troops being created in Russia (which commander has become general Pierre Janin), the Bolshevik army still achieved success. The activities of the 1st, 2ndand 3rd riflemen regiments of polish division on thenorth from Nowoniko3ejewsk could not improve the situation. Facing a continuously worsening situation, General Janin commanded a general evacuation to the east and designated the 5th Division of Polish Riflemen to be rear guard which had to follow the Czechoslovakian Corps. After the Japanese and Czechoslovakian units, the 5th Division of Polish Riflemen was the most numerous allied military formation in East Russia and Siberia.
EN
The aim of this paper was to study comparatively the amount, chemical composition and energy content of litter from forest and grassland ecosystems along a transect in Central Siberia, running from the north (68[degrees] N, Forest tundra) to the south (50[degrees] N, Dry steppes); it is about 2 000 km. In the boreal forests litter standing crop ranges from 15 to 78 t[x]ha^-1 d.w., in subboreal birch stands - it is about 17 t[x]ha^-1 d.w. and in grasslands - the litter standing crop decreases southward along the transect from 6 to 1.5 t[x].ha^-1 d.w. All kinds of litter are rich in reduced compounds and have negative oxidation degree. Nevertheless oxidation degree increased from North to South in both ecosystem groups: from -0.6 to -0.3 in the boreal forests and from -0.5 to -0.2 in the subboreal ecosystems. The chemical composition of litter is specific and differs from both initial substrates, i.e. phytomass and products of humification. The litter contains as many carbon as many as fulvic acids, as many oxygen as humic acids and much more hydrogen than both acids together. Energy content values of litter were estimated to be lower than that of humic acids and higher than energy contents of fulvic acids. The transformation of litter organic substances seems to be shifted to the formation of fulvic acids.The content of minerals in litter changed in both series (forest and grassland) in the following order Si> Ca> F> Al> S> Mg> K> P> Na.
EN
Published sulphur and oxygen isotope age curves for the late Neoproterozoic-Early Cambrian time interval have been based on studies of sulphate intervals of the East Siberian salt giant. We report here on sulphur and oxygen measurements for sulphate dispersed in, or forming laminae in, the rock salt deposits in all Lower Cambrian basins of East Siberia. Sulphur isotope data for 26 samples of Lower Cambrian anhydrites from East Siberia range from +22.6 to +34.5‰. No difference was observed between different suites and between samples taken from anhydrite intercalations in rock salt and from water-insoluble residue in rock salt. Oxygen isotope data for 25 anhydrite samples range from +12.4 to +17.8‰, and thus δ18 O values have a smaller range of variation (5.5‰) than δ34 S (11.8‰) over the entire set of Lower Cambrian anhydrites. The great δ34 S variability observed in the Lower Cambrian of Siberia seems to reflect mixing of sulphates coming from the ocean and due to the riverine input. The lowest δ18 O values may indicate the input values from both the sources, whilst the highest value may result from isotope exchange between SO4 2- and water. Our results combined with data provided by previous workers could indicate a clear stratigraphic trend in δ34 S values, with a remarkable fall of ca. 9‰ in δ34 S value during the earliest Cambrian and then a slight rise in δ34 S values in the younger part of Early Cambrian. However, if only the highest values are taken, the measured values are compatible with seawater δ34 S 3 30‰ during the entire Early Cambrian. Sulphur isotopic composition of sulphate minerals did not be come heavier from the sulphate stage to ward the chloride stage.
16
EN
Phosphatized palaeoscolecid cuticle fragments of Palaeoscolex lubovae sp. nov., P. spinosus sp. nov., Palaeoscolex sp. and Sahascolex labyrinthus gen. et sp. nov., as well as disarticulated sclerites, are described from the Early Cambrian Sinsk Formation (Siberian Platform) at the Achchagyy Tuoydakh fossil-Lagerstatte. These remarkably well preserved arrays of plates and platelets display ornamentation identical to widely reported isolated sclerites assigned to Hadimopanella, Kaimenella, Milaculum, and Utahphospha. The precise relationship of the Palaeoscolecida to the priapulids or alternatively with the nematomorphs remains under discussion, but suggested is their systematic position within the superphylum Ecdysozoa, comprising moulting animals. some of the described cuticular trunks exhibit distinction between the dorsal and ventral sides: nodular sclerites occur on the dorsal and spiny sclerites on the ventral sides of the worm body. Such a pattern of ornamentation may suggest adaptation for a level-bottom, vagile benthic and probably epifaunal mode of life. The Siberian palaeoscolecids are compared with the type species of Palaeoscolex, P. piscatorum Whittard, 1953, and with palaeoscolecid worms from Australia, Bohemia and China. Sclerites recorded with microplates accreted into the basal brim may support a hypothesis that the more complex sclerite structure bearing a series of nodes was derived from simple small sclerites with single node. The biostratigraphic utility of isolated sclerites remains low, because of the same morphology occur in different sclerites may occur in one scleritome.
17
Content available remote A unified Lower - Middle Cambrian chronostratigraphy for West Gondwana
EN
Similarities in biotic successions support a unified, composite chronostratigraphy for the Lower-Middle Cambrian of the Iberian and Moroccan margins of West Gondwana. The Curdubian Series (emended from an Iberian stage-level unit) comprises the sub-trilobitic Lower Cambrian of West Gondwana. This series represents ca. half of the Cambrian (ca. 25 m.y.), has a base defined at the lowest occurrence of diagnostic Cambrian ichnogenera in central Spain, and is comparable to the Placentian Series of Avalon. The overlying trilobite-bearing Lower Cambrian (ca. 9 m.y. duration), or Atlasian Series (new), of West Gondwana consists of two stages originally defined in highly fossiliferous (trilobites and archaeocyaths) Moroccan sections where they have great potential for precise U-Pb geochronology. The penultimate Lower Cambrian stage, the Issendalenian, with the near-joint lowest occurrence of trilobites and archaeocyaths, is approximately comparable with the sparsely fossiliferous, Iberian"Ovetian Stage" (designation abandoned). The "Ovetian" as currently revised is invalid because it is an objective homonym of Sdzuy's original "Ovetian". The "Ovetian" is not a practically applicable unit as its basal stratotype horizon lacs any identified fossils, and its trilobites are so rare that it cannot serve as a standard for interregional correlation. By contrast, the Banian Stage as defined in Marocco is suitable as the terminal Lower Cambrian stage of West Gondwana. It is based on very fossiliferous successions that allow recognition of three successive trilobite zones and is similar in concept to the Iberian 'Marianian Stage' (designation abandoned). The "Marianian" lacs a designated lower boundary stratotype locality, lacs a biostratigraphically defined base at a stratotype, and is so sparsely fossiliferous that no biostratigraphic zonation exists. Long-term problems involving regional definition of the West Gondwana Lower-Middle Cambrian boundary are resolved. The lowestoccurrence of paradoxidid trilobites, the classic index for the base of the Middle Cambrian, is diachronous in West Gondwana and other regions, with the group showing a delayed appearance in Iberia, Sweden, and Bohemia, by comparison with Morocco. Taxonomic revision of Iberian trilobites and new documentation of their ranges in Morocco show that the Iberian terminal "Lower Cambrian" "Bilbilian Stage" (designation abandoned) correlates with the Moroccan upper Banian and lower and middle "Tissafinian" Stages and with the Siberian upper Toyonian (traditionally assigned to the Lower Cambrian in Siberia) and lower Amgan (assigned to the Middle Cambrian in Siberia) Stages. The "Bilbilian" thus includes Middle Cambrian strata in a traditional international concept. Faunas from the base of the Iberian "lowest" Middle Cambrian "Leonian Stage" (designation abandoned) correlate largely into the second trilobite zone of the "Tissafinian" and are now understood to appear above an intra-Middle Cambrian faunal break. This faunal break is still poorly understood and may be an artifact of collection failure immediately above the sparsely fossiliferous, problematical "Valdemiedes event" interval. The base of this "Middle Cambrian", now termed Celtiberian Series (new designation), in west Gondwana is best defined by the base of the lower Middle Cambrian Agdzian Stage (new designation). The Agdzian includes the "Tissafinian" and overlying lower "Toushamian Stage" (designations abandoned) of Morocco, and has its top defined by the base of the middle Middle Cambrian Caesaraugustian Stage, as defined in Spain at the lowest occurrence of Badulesia tenera. The Languedocian, originally defined at the lowest occurrence of Solenopleuropsis (Manublesia) thorali in the southern Montagne Noire of France comprises the third, and terminal stage of the Celtiberian Series. We suggest that the designations "Lower Cambrian" and "Middle Cambiran" be regarded as descriptive and nonchronostratigra-phic terms in discussions of the Cambrian. New taxa or taxonomic combinations include Myopsolenites altus (Linan & Gozalo, 1986), M. boutiouiti sp. nov., M. kielciensis (Bednarczyk, 1970), and Hamatolenus (Hamatolenus) vincenti sp. nov.
EN
To solve the question concerning the age and extent of the latest glaciation in northern Eurasia, several geological investigations were carried out. This paper describes work done on the North Taymyr ice-marginal complex on the Taymyr Peninsula in north central Siberia. The initial remote sensing work aimed to survey fieldwork localities and to acquire a regional geological overview. A Landsat 5 Multispectral Scanner (MSS) image was interpreted, both visually and by computer-based techniques. The ice-marginal zone is clearly visible on the satellite image and it was possible to distinguish spectrally different ground-types. In total, seven ground-types have been discerned and they are described and discussed. A geological interpretation of them was made after combining the initial results with the information gained from ground-truthing, which included sedimentological and morphological fieldwork. It is necessary to take topography and associations of classes into consideration when interpreting the final map, since the identification of some ground-types is not univocal.
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