scholarly journals Tectonomagmatic considerations about the Cimmerian metamorphism and magmatism in Bulgaria

2021 ◽  
Vol 82 (3) ◽  
pp. 94-96
Author(s):  
Ivan Zagorchev
Keyword(s):  
Plate Tectonics ◽  
Balkan Peninsula ◽  
European Continent ◽  
Igneous Activity

Problems of the Cimmerian igneous activity are briefly discussed at the background of the plate tectonics of the Balkan Peninsula. We mostly comment on the relations of the tectonometamorphic evolution of the Bulgarian territory with the Vardar Ocean and its subduction beneath the European continent. A number of problems still remain open especially in regard to the Jurassic evolution of the Rhodope massif.

Evolution of the Martian Crust

2017 ◽  
Author(s):  
John C. Bridges
Keyword(s):  
Plate Tectonics ◽  
Chemical Weathering ◽  
Compositional Data ◽  
Crustal Contamination ◽  
Planetary Science ◽  
Mantle Metasomatism ◽  
Igneous Rocks ◽  
Forthcoming Article ◽  
Physical Weathering ◽  
Igneous Activity

This is an advance summary of a forthcoming article in the Oxford Encyclopedia of Planetary Science. Please check back later for the full article.Mars, which has a tenth of the mass of Earth, has cooled as a single lithospheric plate. Current topography gravity maps and magnetic maps do not show signs of the plate tectonics processes that have shaped the Earth’s surface. Instead, Mars has been shaped by the effects of meteorite bombardment, igneous activity, and sedimentary—including aqueous—processes. Mars also contains enormous igneous centers—Tharsis and Elysium, with other shield volcanoes in the ancient highlands. In fact, the planet has been volcanically active for nearly all of its 4.5 Gyr history, and crater counts in the Northern Lowlands suggest that may have extended to within the last tens of millions of years. Our knowledge of the composition of the igneous rocks on Mars is informed by over 100 Martian meteorites and the results from landers and orbiters. These show dominantly tholeiitic basaltic compositions derived by melting of a relatively K, Fe-rich mantle compared to that of the Earth. However, recent meteorite and lander results reveal considerable diversity, including more silica-rich and alkaline igneous activity. These show the importance of a range of processes including crystal fractionation, partial melting, and possibly mantle metasomatism and crustal contamination of magmas. The figures and plots of compositional data from meteorites and landers show the range of compositions with comparisons to other planetary basalts (Earth, Moon, Venus). A notable feature of Martian igneous rocks is the apparent absence of amphibole. This is one of the clues that the Martian mantle had a very low water content when compared to that of Earth.The Martian crust, however, has undergone hydrothermal alteration, with impact as an important heat source. This is shown by SNC analyses of secondary minerals and Near Infra-Red analyses from orbit. The associated water may be endogenous.Our view of the Martian crust has changed since Viking landers touched down on the planet in 1976: from one almost entirely dominated by basaltic flows to one where much of the ancient highlands, particularly in ancient craters, is covered by km deep sedimentary deposits that record changing environmental conditions from ancient to recent Mars. The composition of these sediments—including, notably, the MSL Curiosity Rover results—reveal an ancient Mars where physical weathering of basaltic and fractionated igneous source material has dominated over extensive chemical weathering.

Political and Socio-Economic Repercussions of the 1877-78 Russo-Turkish War

1979 ◽  
Vol 6 (1) ◽  
pp. 233-245
Author(s):  
Simeon Damianov
Keyword(s):  
Balkan Peninsula ◽  
Past Century ◽  
Southeastern Europe ◽  
European Continent ◽  
Economic Changes ◽  
The Road ◽  
Progressive Development ◽  
The Sixties ◽  
Eastern Question ◽  
History Of Europe

AbstractThe war waged by Russia against the Ottoman Empire in 1877-78, was one of the most important events in the history of Europe in the second half of the nineteenth century. Its significance for Southeastern Europe may be compared to such events of first-rate importance as Germany's and Italy's national unifications in the sixties and the early seventies of the past century. Without any exaggeration it may be stated that diplomatic activities of the large European countries on the eve and in the course of the war were unprecedented in scale. The Great Powers were well aware of the fact that the Eastern Question had reached its decisive phase, that the war inevitably would lead to profound political and economic changes on the Balkan Peninsula, and these changes would affect their age-old interests in the Near East. It is for these reasons that they committed themselves directly to the dramatic duel which began on Bulgarian land after the Russian troops crossed the Danube toward the end of June, 1877. The major political result of the war was Bulgaria's liberation from a five-century long Ottoman rule and the restoration of its national independence. But the war dealt a crushing blow to the decadent Ottoman military-feudal system in all of Southeastern Europe and opened up wide prospects for the progressive development not only of the Bulgarians but also of the other Balkan peoples. An important step was taken along the road for the liquidation of national oppression and for the achievement of a transition from feudalism to capitalism in one of the most beautiful parts of the European continent, whose development had been delayed for ages.

A Discussion on global tectonics in Proterozoic times - Early and Middle Proterozoic history of the Great Lakes area, North America

1976 ◽  
Vol 280 (1298) ◽  
pp. 605-628 ◽  
Keyword(s):  
North America ◽  
Plate Tectonics ◽  
Regional Metamorphism ◽  
Volcanic Rocks ◽  
Low Grade ◽  
Tectonic Event ◽  
Early Proterozoic ◽  
Igneous Activity ◽  
Area North ◽  
Orogenic Belts

Two major supracrustal sequences, the Huronian Supergroup in Ontario and the Marquette Range Supergroup and Animikie Group of Michigan and Minnesota, overlie an Archean basement. These sequences are about 2200—2300 Ma and 1900-2000 Ma old respectively. The major Early Proterozoic tectonic event is the ‘Penokean Orogeny’, which occurred about 1850-1900 Ma ago and included deformation, high-grade regional metamorphism, and extrusive and intrusive igneous activity. This was followed by formation of rhyolitic, ignimbritic volcanic rocks and emplacement of associated granites about 1790 Ma ago. The entire region was subsequently subjected to low-grade regional metamorphism 1650-1700 Ma ago, followed by emplacement of anorogenic quartz-monzonite, in part rapakivi, plutons 1500 Ma ago. Late Proterozoic Grenville and Keweenawan events represent the youngest major Precambrian activity in the region. The rocks involved in the Penokean Orogeny lie along the southern margin of the Archean craton of the Superior Province and are interpreted as representing Early Proterozoic cratonic-margin orogenic activity. The distribution of rocks types and structures associated with the Penokean Orogeny and with similar orogenic belts along the margin of the Archean craton of North America suggest that these orogenic belts may have formed as a result of processes similar to modern plate tectonics, although the data are far from conclusive at present.

scholarly journals Palaeozoic and Mesozoic igneous activity in the Netherlands: a tectonomagmatic review

2004 ◽  
Vol 83 (2) ◽  
pp. 113-134 ◽  
Author(s):  
W. Sissingh
Keyword(s):  
The Netherlands ◽  
Plate Tectonics ◽  
Tectonic Stress ◽  
Late Triassic ◽  
Stress Regime ◽  
Production Wells ◽  
Exploration And Production ◽  
Igneous Activity ◽  
History Of ◽  
Early Late

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.

The Bulgarian Medieval State: Seventh To Fourteenth Centuries

1981 ◽  
Vol 8 (1) ◽  
pp. 19-39
Author(s):  
Vassil Giuzelev
Keyword(s):  
International Relations ◽  
Middle Ages ◽  
Balkan Peninsula ◽  
Political Factor ◽  
European Continent ◽  
Comprehensive Examination ◽  
History Of ◽  
History Of Europe ◽  
European Family ◽  
The Middle Ages

AbstractThe Bulgarian State has had an independent historical existence and sovereignty for 552 years, from its foundation on the Balkan Peninsula in 681 to its destruction under the assaults of the Ottoman Turks in 1396. It was this long historical existence that was conducive in the Middle Ages to the formation of a staunch and sturdy Bulgarian ethnical community to be preserved throughout the centuries, irrespective of great historical vicissitudes. The medieval Bulgarian state was a considerable political factor in the history of Europe, and of the Balkan Peninsula in particular. It maintained various relations with neighboring and distant states. While the nature of these relations changed with the various periods, they depended on certain factors that had a marked reflection on Bulgaria's international ties and determined the direction of its development. These factors have had basic importantance: 1) the territorial size and the ethnical and military potential of the Bulgarian state; 2) its public and administrative setup and its institutions; 3) the nature and development of its international relations, and 4) the position and the part played by its ruler in the Medieval European "family of rulers and nations." Each of these factors was a precondition for the evolvement of the others. If these factors are to be reviewed through their effects, a possibility is at hand to reveal the role and importance of the Medieval Bulgarian state on the European continent. So far, historiographic attempts to generalize this problem have been a comprehensive examination of the history of the Bulgarian state at its peak moments.1

A Discussion on the evolution of the Precambrian crust - Tectonic displacements and thermal activity in two contrasting Proterozoic mobile belts from Greenland

1973 ◽  
Vol 273 (1235) ◽  
pp. 513-533 ◽  
Keyword(s):  
Plate Tectonics ◽  
Regional Metamorphism ◽  
The Other ◽  
Crustal Thickening ◽  
Thermal Activity ◽  
Crustal Shortening ◽  
Granite Intrusion ◽  
Igneous Activity ◽  
History Of ◽  
The One

The Proterozoic Nagssugtoqidian and Ketilidian mobile belts are comparable in scale with those of the Phanerozoic rather than those of the Archaean. These two Proterozoic belts differ from one another both in the tectonic displacements which gave rise to them, and in their thermal activities as expressed by igneous and metamorphic characteristics. Similar differences between modern tectonic belts have been interpreted in terms of plate tectonics. The Nagssugtoqidian is characterized by considerable crustal shortening, very limited igneous activity, and high-pressure regional metamorphism which may be related to crustal thickening resulting from both ductile and brittle overthrusting of the Nagssugtoqidian rocks over the Archaean foreland. Evidence of crustal shortening in the Ketilidian is limited, but vertical and transcurrent movements are important. Widespread igneous activity throughout the active history of the belt resulted in the formation of mainly acid volcanic supracrustal rocks and widespread granite intrusion. The appinite suite is also well represented. Metamorphism is mainly of low-pressure type. A tentative comparison can be made between the Alpine and Nagssugtoqidian belts on the one hand, and Andean and Ketilidian belts on the other.

HPLC-DAD/ESI-MS identification and quantification of polar constituents in six Stachys taxa from Balkan peninsula

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
A Karioti ◽  
J Kukic Markovic ◽  
S Petrovic ◽  
M Niketic ◽  
A Bilia
Keyword(s):  
Balkan Peninsula ◽  
Esi Ms ◽  
Identification And Quantification

New forms of intra-European migration, labour market dynamics and social inequality in Europe

2014 ◽  
Vol 11 (2) ◽  
pp. 125-136 ◽  
Author(s):  
Roland Verwiebe ◽  
Laura Wiesböck ◽  
Roland Teitzer
Keyword(s):  
Labour Market ◽  
Social Inequality ◽  
Social Stratification ◽  
Labour Markets ◽  
Second Step ◽  
Market Dynamics ◽  
Migration Patterns ◽  
European Continent ◽  
The Past ◽  
European Migration

This article deals mainly with new forms of Intra-European migration, processes of integration and inequality, and the dynamics of emerging transnational labour markets in Europe. We discuss these issues against the background of fundamental changes which have been taking place on the European continent over the past two decades. Drawing on available comparative European data, we examine, in a first step, whether the changes in intra-European migration patterns have been accompanied by a differentiation of the causes of migration. In a second step, we discuss the extent to which new forms of transnational labour markets have been emerging within Europe and their effects on systems of social stratification.

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