Author: Henning Sorensen
Publisher: Museum Tusculanum Press
Published: 2006
Total Pages: 74
ISBN-13: 9788763512718
DOWNLOAD EBOOK →The Ilimaussaq alkaline complex, South Greenland, the type locality of agpaitic nepheline syenites and of thirty minerals, among which arfvedsonite, eudialyte and sodalite, has been studied since 1806. The paper reviews the outcome of 200 years of geological investigations and presents an overview and a synthesis of the petrology of the complex. According to one model for the evolution of the complex, the nepheline syenites formed by consolidation of one magma batch in a closed system. The lujavrites were formed from the residual melts left after the formation of the roof series and the floor series and were sandwiched between these. A second model implies that the kakortokites and lujavrites formed from one or more separate magma pulses which intruded the already consolidated roof series rocks. This model is supported by new information on contact relations and especially on the petrology and geochemistry of a marginal pegmatitic fades that forms a rim around the kakortokite-lower aegirine lujavrite part of the complex. It consists of a massive-textured matrix intersected by pegmatites. The matrix was the first rock to form in the lowermost exposed part of the complex and gives information about the composition of the initial magma of the kakortokite-lujavrite sequence. It is concluded that the agpaitic rocks of the complex were formed from at least two successive magma injections, which formed respectively the roof series and the kakortokite-lujavrite sequence.
Author:
Publisher: Museum Tusculanum Press
Published:
Total Pages: 68
ISBN-13: 9788763512589
DOWNLOAD EBOOK →Author: Denmark. Kommissionen for videnskabelige undersøgelser i Grønland
Publisher:
Published: 1918
Total Pages: 35
ISBN-13:
DOWNLOAD EBOOK →Author: Ismar Borges De Lima
Publisher: Elsevier
Published: 2015-09-10
Total Pages: 468
ISBN-13: 0128025689
DOWNLOAD EBOOK →Rare Earths elements are composed of 15 chemical elements in the periodic table. Scandium and yttrium have similar properties, with mineral assemblages, and are therefore referred alike in the literature. Although abundant in the planet surface, the Rare Earths are not found in concentrated forms, thus making them economically valued as they are so challenging to obtain. Rare Earths Industry: Technological, Economic and Environmental Implications provides an interdisciplinary orientation to the topic of Rare Earths with a focus on technical, scientific, academic, economic, and environmental issues. Part I of book deals with the Rare Earths Reserves and Mining, Part II focuses on Rare Earths Processes and High-Tech Product Development, and Part III deals with Rare Earths Recycling Opportunities and Challenges. The chapters provide updated information and priceless analysis of the theme, and they seek to present the latest techniques, approaches, processes and technologies that can reduce the costs of compliance with environmental concerns in a way it is possible to anticipate and mitigate emerging problems. Discusses the influence of policy on Rare Earth Elements to help raise interest in developing strategies for management resource development and exploitation Global contributions will address solutions in countries that are high RE producers, including China, Brazil, Australia, and South China End of chapter critical summaries outline the technological, economic and environmental implications of rare earths reserves, exploration and market Provides a concise, but meaningful, geopolitical analysis of the current worldwide scenario and importance of rare earths exploration for governments, corporate groups, and local stakeholders
Author: Henning Sørensen
Publisher: Grnlands Geologiske Undersgelse Eksp. C. A. Reitzel
Published: 1974
Total Pages: 76
ISBN-13:
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