Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
Central America comprises 7 countries (Fig. 1.1) that cover 50 million hectares extending over different ecoregions (Fig. 1.2a) and shelter nearly 39 million people (2003). With a relatively high population density (71 inhabitants/km2), Central America is one of the world’s regions most prone to geology-related and climaterelated natural disasters. Earthquakes and volcanic eruptions, which are related to the Central American tectonic setting, and landslides, which are either earthquake induced or rainfall-related, are the most severe geological burdens of the region. Central America also is afflicted by several climatic hazards, particularly droughts and hurricanes, which may be accompanied by secondary hazards, including high winds, flooding and landslides.
Questions of morphological study addressing living and fossil organisms are briefly discussed. The importance of ontogenetic patterns and processes in evolutionary biology are viewed on the background of three special problems of cephalopod morphology: the reproductive system of octopods, the lower beaks of coleoids and ammonites, and the arm crown of the coleoids. <...>
Cephalopods are diverse, highly developed molluscs capable of swimming and jet propulsion. These animals are an important component of present-day marine ecosystems throughout the world and comprise approximately 900 species. They also have an extraordinary fossil record, extending back to the Cambrian Period, with as many as 10,000 extinct species. Throughout their long history, they have experienced spectacular radiations and near-total extinctions. Because of their superb fossil record, they also serve as ideal index fossils to subdivide geologic time. This book touches on many of these themes, and it treats both fossil and present-day cephalopods. The chapters are outgrowths of presentations at the Sixth International Symposium “Cephalopods – Present and Past,” at the University of Arkansas in Fayetteville, September 16–19, 2004. The Symposium was organized principally by Walter L. Manger of the Department of Geology, University of Arkansas. The editors gratefully acknowledge Walter for his terrific job in putting together this symposium and for making it such an intellectual, and social, success. Other publications related to this Symposium include the abstract volume, assembled by W. L. Manger, and two fieldtrip guidebooks, one written by W. L. Manger, and the other by R. H. Mapes. <...>
This book is intended to be a concise and comprehensive coverage of the key ceramic and glass materials used in modern technology. A group of international experts have contributed a wide ranging set of chapters that literally covers this field from A (Chap. 1) to Z (Chap. 10). Each chapter focuses on the structure–property relationships for these important materials and expands our understanding of their nature by simultaneously discussing the technology of their processing methods. In each case, the resulting understanding of the contemporary applications of the materials provides insights as to their future role in twenty-first century engineering and technology <...>
It would be a misstatement to claim that this title provides an “exhaustiveness” coverage of the world of ceramic materials, if only because this subject covers such a wide area that only one book would not be able to do it justice – even if it is supplemented by a book dedicated to ceramic composites and by several volumes devoted to the cousins of ceramics, namely glasses, cements and concretes, and geomaterials. However, we believe that this problem can also be an advantage,because it resulted in the production of a concise work that provides the essence of the subject.
This work could not even have been attempted, much less completed, without the help of numerous friends and colleagues. In roughly chronological order (my sample collecting formally began in 1985), I extend my sincerest thanks to the following people, beginning with those based in Ohio institutions: N’omi Greber and David Brose, then at the Cleveland Museum of Natural History; Olaf Prufer and Mark Seeman at Kent State University;
Распределение халькофильных элементов и элементов платиновой группы в ультраосновных породах комплекса Стиллуотер, Массачусетс, США - влияние на процессы обогащения слоев хромита Os, Ir, Ru и Rh
All of the rocks from the Ultramafic series of the Stillwater Complex are enriched in PGE relative to most mafic magmas. Furthermore, the chromite layers are particularly enriched in IPGE (Os, Ir, and Ru) and Rh. This enrichment appears to be a common characteristic of ultramafic rocks from many types of settings, layered intrusions, ophiolites, and zoned complexes.
Even though our limited perceptions provide us with only a brief glimpse of the Universe, the main lesson that we learn from our observation is that the world is complicated. Very complicated. Every part of the universe interacts with the other parts; the responses of each component are never proportional to the applied forces, and the feedbacks of one subsystem on another cannot be discarded. As a result, processes are unpredictable, and chaotic behavior is a common occurrence. Disorder and turbulence become rife. Yet from the chaotic background, coherent structures sometimes emerge, patterns form, and local order is generated.
The Jerónimo sedimentary rock-hosted disseminated Au deposit is located within the Potrerillos district of the Atacama region of northern Chile, east of the Potrerillos porphyry Cu-Mo and El Hueso high-sulfidation Au deposits. Prior to development, the Jerónimo deposit contained a resource of approximately 16.5 million metric tons (Mt) at 6.0 g/t Au. Production began in the oxidized, nonrefractory portion of the deposit in 1997 and terminated in 2002. During that time, approximately 1.5 Mt at 6.8 g/t Au was mined by underground room-and-pillar methods, from which a total of approximately 220,000 oz of Au was recovered by heap-leach cyanidation.
