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Выпуск 24
Автор(ы):Keewook Y., Wintsch R.P.
Издание:Journal of Structural Geology, 2002 г., 15 стр.
Язык(и)Английский
Dissolution and replacement creep: a significant deformation mechanism in mid-crustal rocks

Zoning patterns and zoning truncations in metamorphic minerals in a granodioritic orthogneiss indicate that strain and S-C fabrics in these rocks were produced by dissolution, precipitation, and replacement processes, even at epidote-amphibolite fades metamorphic conditions. The metamorphic fabric is defined by alternating layers and folia dominated by quartz, feldspars, and biotite + epidote. Zoning patterns in most metamorphic plagioclase, orthoclase, epidote, and sphene are truncated at boundaries normal to the shortening direction, suggesting dissolution. Interfaces of relict igneous orthoclase phenocrysts that face the shortening direction are embayed and replaced by biotite, epidote, and myrmekitic intergrowths of plagioclase and quartz. Metamorphic plagioclase grains are also replaced by epidote. We interpret these microstractures to reflect strain-enhanced dissolution. The cores of many grains show asymmetric overgrowths with at least two generations of beards, all oriented on the ends of grains that face the extension direction. We interpret these textures to reflect precipitation of components dissolved by deformation-enhanced dissolution. While biotite and quartz probably deformed by dislocation creep, the overall deformation was accommodated by dissolution perpendicular to the shortening direction, and precipitation parallel to it. These chemical processes must have been activated at lower stresses than the dislocation creep predicted from extrapolations of data from experiments in dry rocks. Thus wet crust is likely to be weaker than calculated from these experimental studies

Выпуск 76
Автор(ы):Almeras Y., Peybernes B.
Издание:Lyon, 1979 г., 112 стр.
Язык(и)Французский
Documents des laboratoires de geologie de la faculte des sciences de Lyon. Les brachiopodes du dogger des pyrenees Navarro-Languedociennes

Au cours de la revision stratigraphique du Dogger des Pyrenees Navarro-Languedo- ciennes (Peybernbs, 1976), des gisements de brachiopodes ont ete signals tant dans les Pyrenees fran- gaises (Corbiferes essentiellement) qu'espagnoles. Ces brachiopodes ddtermines (Y. Almiras) et replaces dans les coupes stratigraphiques (PeybernSs, 1976) sont ici etudies par les methodes biometriques classi- ques (dynamique des populations, ontogenese) et &. l'aide des coupes seriees (caracteres internes). Grace a nos connaissances sur la biostratigraphie de ces memes especes de brachiopodes dans d'autres regions, nous avons pu confirmer ou prdciser la datation encore incertaine de plusieurs niveaux du Dogger. <...>

Автор(ы):Yang Chang-Shu
Издание:Instituut voor Aardwetenschappen der Rijksuniversiteit te Utrecht, 1989 г., 160 стр., ISBN: 90-71577-13-9
Язык(и)Английский
Dynamics and sedimentary facies analysis of clastic tidal deposits

One of the most important dynamic processes in the ocean is that of tidal movement. The tides obtain their energy from the earth's rotation. Most of this energy is received in the major ocean basins, and from there transmitted into shallow waters. It is in these shallow waters that tidal energy is dissipated, in part by eroding and transporting sediments, resulting in very active sedimentary processes in the shelf and coastal areas.

Research in clastic tidal deposits has accumulated large-amount of data on tidal processes and their products. In present-day tide-swept shelves large-scale tidal sandbodies with various bedforms has been a subject of extensive research, which mainly focussed on the southern bight of the North Sea (van Veen, 1935; Jones, Kain & Stride, 1965; Houbolt, 1968; Stride, 1970; Caston & Stride, 1970,1973; McCave, 197.1; Terwindt, 1971,1973; Cas-ton, 1972; Johnson et al., 1981; Kenyon et al., 1981; Langhorne, 1982; McCave & Lan-ghorne, 1982; Nio & Nelson, 1982; Stride, 1982; de Boer, van Gelder & Nio, 1988), the English Channel and the French Atlantic shelf (Berne et al., 1986; Berne et al., 1988; Turcq et al, 1986) and the North American Atlantic shelf (Swift et al., 1972,1979,1981; Milliman etal., 1972; Sheridan etal, 1974;Knebel&Folger, 1976,Knebel, 1981; Swift & Field, 1981).

In estuaries and other inshore tidal basins, genesis, geometry, distribution pattern, dynamic behaviour and internal sedimentary structures of tidal bedforms have been studied intensively in the Netherlands (Boersma, 1969; Terwindt, 1970,1981; de Raaf & Boersma, 1971; Boersma & Terwindt, 1981; Kohsiek & Terwindt, 1981; van den Berg, 1982, 1984, 1987; Terwindt & Brouwer, 1986; de Boer, van Gelder & Nio, 1988), U.K. (Langhorne, 1973; Allen & Friend, 1976; Elliott & Gardiner, 1981), France (Tastet et al, 1986), United States (Boothroyd & Hubbard, 1975; Bokuniewicz, et al, 1977), Canada (Swift et al, 1966; d'Anglejan, 1971; Dalrymple et al, 1975,1978; Dalrymple, 1984) and other countries. Most of the studies were concentrated in intertidal areas. The subtidal deposits received less attention due to the difficulties in field observations. Preservation potential of subtidal deposits, however, is much higher. As a consequence subtidal deposits will occur more often in the geological record. It is from the detailed study of the subtidal deposits in the construction pits of the Oosterschelde, SW Netherlands that distinct diagnostic criteria for recognizing tide-dominated deposits were developed (Visser, 1980; Siegenthaler, 1982; van den Berg, 1982; Nio et al., 1983; de Mowbray & Visser, 1984; Yang & Nio, 1985). <...>

Издание:Russian Geology and Geophysics, 2011 г., 15 стр.
Язык(и)Английский
Early–Middle Ordovician nappe tectonics of the junction between the Kokchetav HP-UHP metamorphic belt and the Stepnyak paleoisland arc

The North Kokchetav tectonic zone is located between the Kokchetav HP-UHP metamorphic belt and the Stepnyak zone of Ordovician island arc and oceanic complexes. The Kokchetav zone is a collage of nappes (thrust sheets) that consist of basement gneiss and sedimentary rocks of the Kokchetav microcontinent, granite gneiss, mica schists with eclogite blocks, the Shchuch’e ophiolite, Middle Proterozoic felsic volcanics, and Arenigian siliceous-terrigenous sediments with olistostromes. The latter are of gravity-sliding origin and their clastic material includes quartz-muscovite and quartz-garnet-muscovite schists, gneiss, dolomite, and amphibolite. The sheet boundaries are marked by mylonite and Early Ordovician mica schists (40Ar/39Ar ages of syntectonic muscovite are 489–469 Ma). The North Kokchetav collage of compositionally diverse thrust sheets can be interpreted as a collisional zone. According to geological evidence, tectonic activity in the zone lasted as late as the Middle Ordovician. Syncollisional thrusting in the North Kokchetav zone was coeval with the latest dynamic metamorphic event in the history of the Kokchetav belt. All events of retrograde metamorphism and exhumation of HP and UHP rocks in the belt have Cambrian ages, i.e., the rocks had been exhumed prior to the Early–Middle Ordovician collisions and the related orogeny.

Автор(ы):Ben A., Stephen Marshak
Издание:W. W. Norton & Company, 2004 г., 672 стр., ISBN: 039392467X
Язык(и)Английский
Earth Structure: An Introduction to Structural Geology and Tectonics (Second Edition) / Строение Земли - Введение в структурную геологию и тектонику (второе издание)

This book is concerned with the deformation of rock in the Earth’s lithosphere, as viewed from the atomic scale, through the grain scale, the hand specimen scale, the outcrop scale, the mountain range scale, and the tectonic plate scale. A deformational feature observed on one scale typically reflects processes occurring on other scales. For example, we can’t understand continental deformation without understanding mountains, we can’t understand mountains without understanding folding and faulting, and we can’t understand folding and faulting without understanding ductile and brittle deformation mechanisms at the atomic scale. This book attempts to integrate topics pertaining to all scales of rock deformation, emphasizing the linkages between structural geology and tectonics.

Данная книга рассматривает деформацию пород в литосфере Земли , которая наблюдается на атомном уровне, переходя на масштаб зерна, образца, обнажения, горного хребта и тектонической плиты. Деформационные особенности, наблюдаемые в одном масштабе, закономерно отражают процессы, возникающие в другом масштабе. К примеру, мы не можем понять деформацию континента без понимания процессов горообразования, мы не можем понять горообразование без понимания процессов образования складок и разломов, и мы не можем понять процессы складкообразования и разрывных нарушений без понимания механизмов пластичной и хрупкой деформации на атомарном уровне. Эта книга пытается объединить темы, касающиеся деформации пород на всех уровнях, подчеркивая связь между структурной геологией и тектоникой.

Выпуск 51
Издание:Russian Geology and Geophysics, 2010 г., 15 стр.
Язык(и)Английский
Eclogites of the Late Cambrian–Early Ordovician North Kokchetav tectonic zone (northern Kazakhstan): structural position and petrology

We consider the structural position and petrology of eclogites in the North Kokchetav accretion-collision zone located north of the Kokchetav metamorphic belt formed by high- and ultrahigh-pressure rocks. In the Early Ordovician North Kokchetav tectonic zone, thin sheets of mylonite and diaphthoric gneisses with eclogites are tectonically conjugate with the volcanic and sedimentary rocks of the Stepnyak paleoisland-arc zone. Eclogites have been revealed at two sites of the North Kokchetav tectonic zone—Chaikino and Borovoe. The Chaikino eclogites formed at 800–850 °C and 18–20 kbar, and the Borovoe eclogites, at 750–800 °C and 17–18 kbar. Study of pyroxene-plagioclase symplectite replacing omphacite of the eclogites at both sites has recognized three stages of regressive magmatism: (1) formation of coarse-grained clinopyroxene-plagioclase symplectite at 760–790 °C and 11–12 kbar, (2) formation of fine-grained clinopyroxene-plagioclase symplectite at 700–730 °C and 7–8 kbar, and (3) amphibolization of pyroxene at 570–600 °C and 5–6 kbar. The Ar-Ar age of muscovite from the Borovoe mica schists hosting eclogites is 493 ± 5 Ma, which corresponds to the time of cooling of metamorphic rocks to <370 °C. Hence, the peak of high-pressure metamorphism and all recognized stages of retrograde changes are dated to the Cambrian. The geological data evidence that eclogite-schist-gneiss sheets were localized in the accretion-collision zone and became conjugate with sedimentary and volcanic rocks no later than in the Middle Ordovician

Издание:Менеджер, Москва, 2006 г., 192 стр., ISBN: 5-8346-0321-1
Язык(и)Английский, Русский
Effective english for geo-students / Эффективный курс английского языка для студентов-геологов

Пособие представляет собой оригинальный и динамичный курс английского языка для студентов, изучающих науки о Земле. Позволяет быстро и эффективно овладеть терминологической лексикой и основами речевой деятельности. Имеет надежную научно-методическую базу, прошло апробацию, может использоваться на всех уровнях обучения.

Источник:geo.web.ru
Автор(ы):Bubnoff S.
Издание:Berlin, 1956 г., 833 стр.
Язык(и)Немецкий
Einfuhrung in die Erdgeschichte

Die Erdgeschichte ist der eigenartigste Zweig der Geologie, welcher die kausal-naturwissenschaftliche und die historische Betrachtungsweise verknüpft; sie eignet sich daher besonders gut zur Einführung, sofern eben diese spezifische Betrachtungsweise deutlich gekennzeichnet und klar herausgearbeitet wird. Die Schilderung darf also nicht in einer einfachen Materialsammlung steckenbleiben, sondern muß, von den Voraussetzungen ausgehend, über die Sichtung und Ordnung des Materials zu einem Gesamtbild zu gelangen versuchen, welches, über spezialwissenschaftliche Erkenntnis hinaus, den weltanschaulichen Gehalt der Erdwissenschaft zu kennzeichnen vermag. Wenn auch das Endziel heute noch fern erscheint, so ist doch der Weg klar vorgezeichnet, und ihn den Studierenden kenntlich zu machen, ist der Hauptzweck dieses Buches, im Gegensatz zu den eklektischen Sammlungen eines oft recht heterogenen Tatsachenmaterials in vielen älteren Lehrbüchern.

Автор(ы):Martin-Closas C., Salas C.
Издание:Publicaciobes Universidat de Barcelona, Barcelona, 1995 г., 147 стр.
Язык(и)Испанский
El cretacico inferior del Nordeste de Iberia

On the occasion of the III Colloquium on the Cretaceous of Spain, which took place in More-lla on the 6th, 7th and 8th September 1991 sponsored by the Spanish Group of Mesozoic, there were two field trips to illústrate the present knowledge of the Lower Cretaceous of Northeastern Iberia. These excursions are the object of the present guide-book. In the period passed between when this guide-book was written and its final publication, new results were published which represent a significant increase in our previous knowledge. These publications in international journals, which are referenced at the end of the foreword, together with the figure captions of this guide-book, which have been translated in English, will help the English reader to obtain the information necessary to understand the Lower Cretaceous of Northeastern Iberia.

Автор(ы):Янин Е.П.
Издание:Dialog-MGU Publishers, Москва, 1998 г., 37 стр.
Язык(и)Английский
Electrical Engineering Industry and the Urban Environment (man-made pollution and ecological effects) /  Электротехническая промышленность и городская среда (антропогенные загрязнения и экологические последствия)

This paper displays geoenvironmental aspects of supply and distribution of chemical elements in urban environments related to activities of the electrical engineering enterprises. The paper is based upon the data obtained during the course of studies conducted in Saransk, Republic of Mordovia, Russia. In the methodical aspect, this is a favorable object representing an industrial urban area. Its ecology is dominated by the electrical engineering plants.

Источник:от Автора
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