Metallogeny is the science of ore and mineral deposit formation in geological space and time. Metallogeny is interdisciplinary by nature, comprising elements of natural science disciplines such as ...planetology to solid state physics and chemistry, and volcanology. It is the experimental forefront of research and bold thinking, based on an ever-growing foundation of solid knowledge. Therefore, metallogeny is not a closed system of knowledge but a fast-growing assemblage of structured and unstructured information in perpetual flux. This paper intends to review its current state and trends. The latter may introduce speculation and fuzziness. Metallogeny has existed for over 100 years as a branch of Earth Science. From the discovery of plate tectonics (ca. 1950) to the end of the last century, metallogeny passed through a worldwide phase of formally published ‘metallogenetic’ maps. In the last decades, a rapidly growing number of scientists, digitization and splendid new tools fundamentally boosted research. More innovations may be expected by the growing use of an evolving systematic ‘Geodata Science’ for metallogenic research by an increasingly global human talent pool. Future requirements for metallic and mineral raw materials, especially the critical natural elements and compounds that are needed for the nascent carbon-free economy, already drive activities on stock markets and in the resource industry. State geological surveys, academia and private companies embrace the challenges. The new age requires intensified metallogenic backing. In this paper, principles of metallogeny are recalled concerning concepts and terms. A metallogenic classification of ore and mineral deposits is proposed, and the intimate relations of metallogenesis with geodynamics are sketched (ancient lid tectonics and modern plate tectonics). Metallogenic models assemble a great diversity of data that allow an ever better understanding of ore formation, foremost by illuminating the geological source-to-trap migration of ore metals, the petrogenetic and geodynamic–tectonic setting, the spatial architecture of ore deposits and the nature and precise timing of involved processes. Applied metallogeny allows companies to choose strategy and tactics for exploration investment and for planning the work. Based on comprehensive metallogenic knowledge, mineral system analysis (MSA) selects those elements of complex metallogenic models, which are detectable and can guide exploration in order to support applications such as mineral prospectivity mapping, mineral potential evaluation and targeting of detailed investigations. MSA founded on metallogenic models can be applied across whole continents, or at the scale of regional greenfield search, or in brownfields at district to camp scale. By delivering the fundamental keys for MSA, supported by unceasing innovative research, the stream of new metallogenic insights is essential for improving endowment estimates and for successful exploration.
This book deals with the ways in which empires affect smaller communities – for instance, ethnic groups, religious communities, local or peripheral populations. It addresses Byzantinium, the early ...Islamic World and the West in the 5th to 10th centuries CE, a period with a particular dynamic of imperial formation and decline in Europe and the Mediterranean.
Dieser Band beschäftigt sich mit den Auswirkungen von Imperien auf kleinere Gemeinschaften – zum Beispiel ethnische verbände, religiöse Gemeinschaften, lokale oder periphere Bevölkerungen. Behnadelt werden Byzanz, die frühislamische Welt und der Westen im 5.-10. Jahrhundert n. Chr., eine Zeit von besonders dynamischen Prozessen von Neubildung und verfall von Imperien in Europa und dem Mittelmeeraum.
Times of Upheaval Rychterová, Pavlína; Klaniczay, Gábor; Kras, Paweł ...
2019, 20190415, 2019-06-12
eBook
The volume unites conversations with four masters of Medieval Studies from east-central Europe: János Bak from Hungary, Jerzy Kłoczowski from Poland, František Šmahel from the Czech Republic, and ...Herwig Wolfram from Austria. The interviews made by younger colleagues revealed their engaging life stories. The four academics grew up before and during the war, under Nazi occupation, emerged as young scholars in the difficult post-war period, and, for most of their careers, worked in the shadow of the Iron Curtain, two of them spending most of their lifetimes under communist regimes. The conversations focus on ways in which open-minded young intellectuals became medieval historians under difficult circumstances, on how they experienced the long shadows of totalitarian regimes with their acute sensitivity for historical change, and how their perceptions of the world around them reflected back on their approach to medieval history. The histories of their nations were broken, most of them ceased to exist and were re-established during their lifetimes, came under foreign domination, were split, or their territories shifted – what did that mean for their identities and patriotic feelings? How can the present be reflected in the distant mirror of the medieval past? In this book, the four masters reflect about their lives sharing numerous observations, anecdotes and experiences.
The Avars arrived in Europe from the Central Asian steppes in the mid-sixth century CE and dominated much of Central and Eastern Europe for almost 250 years. Fierce warriors and canny power brokers, ...the Avars were more influential and durable than Attila's Huns, yet have remained hidden in history. Walter Pohl's epic narrative, translated into English for the first time, restores them to their rightful place in the story of early medieval Europe.
The Avarsoffers a comprehensive overview of their history, tracing the Avars from the construction of their steppe empire in the center of Europe; their wars and alliances with the Byzantines, Slavs, Lombards, and others; and their apex as the first so-called barbarian power to besiege Constantinople (in 626); to their fall under the Frankish armies of Charlemagne and subsequent disappearance as a distinct cultural group. Pohl uncovers the secrets of their society, synthesizing the rich archaeological record recovered from more than 60,000 graves of the period, as well as accounts of the Avars by Byzantine and other chroniclers.
In recovering the story of the fascinating encounter between Eurasian nomads who established an empire in the heart of Europe and the post-Roman Christian cultures of Europe, this book provides a new perspective on the origins of medieval Europe itself.
Despite centuries of research, much about the barbarian migrations that took place between the fourth and sixth centuries in Europe remains hotly debated. To better understand this key era that marks ...the dawn of modern European societies, we obtained ancient genomic DNA from 63 samples from two cemeteries (from Hungary and Northern Italy) that have been previously associated with the Longobards, a barbarian people that ruled large parts of Italy for over 200 years after invading from Pannonia in 568 CE. Our dense cemetery-based sampling revealed that each cemetery was primarily organized around one large pedigree, suggesting that biological relationships played an important role in these early medieval societies. Moreover, we identified genetic structure in each cemetery involving at least two groups with different ancestry that were very distinct in terms of their funerary customs. Finally, our data are consistent with the proposed long-distance migration from Pannonia to Northern Italy.
Il contributo rilegge l’etnicità romano-barbarica come costruzione culturale fondata in parte sulla rilettura e sulla riappropriazione di modelli biblici intesi come strumenti fondanti e autorevoli. ...Lo studio tenta di capovolgere il paradigma tradizionale secondo cui l’etnicità sarebbe un portato prettamente “barbarico”, in opposizione all’universalismo cristiano-romano. Seguendo questo modello, la storia europea è spesso stata rappresentata come un conflitto tra principi universali e nazionali. Secondo l’A. il ruolo politico dell’etnicità nell’Europa latina non va considerato, almeno in una certa misura, come un’importazione barbarica. Lungi dal rappresentare un’antitesi alla chiesa universale, l’etnicità assume il suo ruolo politico decisivo proprio attraverso il cristianesimo e, più in particolare, attraverso la ripresa e l’adattamento di taluni modelli di auto-definizione etnica presenti nei testi biblici.
The Avars arrived in Europe from the Central Asian steppes in the mid-sixth century CE and dominated much of Central and Eastern Europe for almost 250 years. Fierce warriors and canny power brokers, ...the Avars were more influential and durable than Attila's Huns, yet have remained hidden in history. Walter Pohl's epic narrative, translated into English for the first time, restores them to their rightful place in the story of early medieval Europe. 'The Avars' offers a comprehensive overview of their history, tracing the Avars from the construction of their steppe empire in the centre of Europe; their wars and alliances with the Byzantines, Slavs, Lombards, and others; their apex as the first so-called barbarian power to besiege Constantinople (in 626); to their fall under the Frankish armies of Charlemagne and subsequent disappearance as a distinct cultural group.
SE Kenya is the world’s largest producer of green vanadium grossular gemstones (tsavorite). Samples from one of the mines near Mwatate, and of occurrences in Tanzania yielded remarkable new insights ...into the genesis of tsavorite. Graphite is intimately associated with V-grossular and is one of the keys to understanding its origin. In the course of this study we found five different types of graphite. Surprisingly, in one graphite type the “Raman-forbidden” and IR-active 867 cm
− 1
band was observed. In this communication, we attempt to find an explanation for this unusual phenomenon. Additionally, our observations also address some of the issues pertaining to the origin of the green grossular-dominated rocks (grossularites), as well as the gem quality tsavorite crystals, since we propose that the anomalous spectroscopic behavior of the graphite is related to the unusual conditions during crystallization of both the grossular and graphite from a near-supercritical volatile- and sulfur-rich silicate melt. The massive green vanadium grossular contains abundant unequivocal crystallized melt inclusions, while the transparent gem quality grossular (tsavorite) displays only fluid inclusions. On the basis of inclusion studies we suggest that anatectic melts originated in the peculiar evaporitic host lithology of the tsavorite deposits. Near peak metamorphic temperatures (~ 700 °C) these liquids occurred as a supercritical volatile-rich “fluid/melt phase” characterized by complete miscibility between H
2
O and silicate liquid. Relatively dry liquid batches precipitated non-transparent green grossular, whereas wet batches segregated fluids that formed transparent tsavorite.
When supercontinent Rodinia began to break up at ~ 800 Ma, wide rifts formed evolving into a passive margin of the Mozambique Ocean. At one stage, organic-rich pelites with gypsum/anhydrite (the ...later host rock of tsavorites) were interbedded with siliciclastics, carbonates, and bimodal volcanic rocks. Later, ocean closure, subduction, collision, and welding of various microcontinents and volcanic arcs formed the Mozambique Belt and at ~ 550 Ma, ended with the assembly of supercontinent Gondwana. In East Africa, deformation and metamorphism climaxed at 615–600 Ma. At peak metamorphic conditions, anatexis of siliciclastic metasediments produced abundant metamorphic mobilizates such as pegmatites and quartz veins. In the graphite schist hosting tsavorites, however, partial melting only produced small fractions of a supercritical hydrous liquid, the peculiar corrosive nature of which was due to the reduction of Ca-sulfate by reaction with organic C. Most of this melt/fluid phase remained within the host but migrated over short distances into structural traps of different origin; turbid green grossular crystallized from the melt and transparent tsavorite from residual fluids.
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