Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
The Precambrian is of very special significance in the evols ution of the Earth’s crust. It represents almo st seven-eighth of the geological history of our planet. During this period of time, lasting approximately 4,000 million years, the basement of continental land masses and the deposits of iron and manganese ore were formed. These latter are of world-wide significance both in quantity and extent. They form part of the natural resources of the geographical environment and their study is important both for developed and developing countries <...>
Gale is pleased to present the third edition of Geo-Data: The World Geographical Encyclopedia. This is the first new edition of Geo-Data since 1989, and it represents a complete revision and updating of that work. The purpose of the book remains unchanged: to provide the reader with the most detailed and comprehensive descriptions available for the physical geography of countries. Geo-Data’s focus and design is unique.
Exploration for Platinum: A Contemporary Viewpoint C.J. MORRISSEY (Riofinex North Ltd, Bristol, UK) The Platinum Market: Recent History and Future Developments C. R. N. CLARK (Johnson Matthey pIc, London, UK)
Evaluation of the Nickel Sulphide Bead Method of Fire-assay for the Platinum-Group Elements using Neutron Activation Analysis S.J. Parry, I. W. Sinclair & M. Asif {Imperial College Reactor Centre, Ascot, UK) Preconcentration of Precious Metals by Tellurium Sulphide Fire-assay Followed by Instrumental Neutron Activation Analysis I. Shazali, L. Van’t dack & R. Gijbels {University of Antwerp, Belgium) The Potential of Fire-assay and ICP-MS for the Determination of Platinum-Group Elements in Geological Materials {Abstract) The late A. R. Date, A. E. Davies & Y. Y. Cheung {British Geological Survey, London, UK) ICP-AES Determination of Precious Metals in Difficult Materials P. Whitehead {Johnson Matthey Technology Centre, Reading, UK) <...>
Of all of the sciences utilized in modern archaeological research, that of geology has the longest history of association with archaeology. Surprisingly, perhaps, geoarchaeology as a recognized sub-discipline has taken slightly longer to establish itself than others such as bioarchaeology. There is still some uncertainty about what exactly geoarchaeology encompasses, and some differences of usage of the term between Europe and North America. This brief introduction explores some of these issues, and attempts to place the other contributions to this volume in a slightly broader context.
Вопрос об образовании гранитоидных пород, известный геологам всего мира как «гранитная проблема», до сих пор не решен, а потому и актуален, однако современные петрологические исследования постепенно проясняют сложную историю этих наиболее распространенных глубинных пород, при этом уделено внимание разнообразию геотектонических обстановок, путям образования и исходному материалу гранитоидных магм, механизмам их возникновения и процессам, вызывающим вариации состава и потенциальной рудоносности гранитоидных тел во времени и пространстве.
Before mentioning the characteristics of Kuroko and epithermal vein-type deposits in Japan, it is worthwhile to briefly describe the metallogeny, geology, geophysics, and tectonic situations of the Japanese Islands.
In this volume John Carranza not only offers a comprehensive review of the current state-of-the-art of processing geochemical data, their integration with complementary geodata sets and multivariate data analysis using spatial statistics to create maps enhanced for mineral exploration, but also brings the Handbook series to something of a milestone. This marks the first volume in which the topic of an earlier volume (Vol. 2) is in effect revisited and updated; though the approach and format are – appropriately – entirely fresh.
In Chapter 1 we noted that magmas with distinctive major element characteristics are associated with specific tectonic settings. For example, calc-alkaline series magmas are apparently associated uniquely with subduction, while low-K tholeiitic basalts are the typical products of magma generation at constructive plate margins. However, in general, the major element characteristics of primary mantle derived magmas are * not particularly sensitive indicators of tectonic setting.
Data presented in this report pertain to the igneous intrusions of north-central and northeast Nevada and were compiled as part of the Metallogeny of the Great Basin project conducted by the U.S. Geological Survey between 2001 and 2007. The geographic area addressed in this compilation is approximately bounded by lats 38.5° and 42°N., long 118.5° W., and the Nevada-Utah border (fig. 1). The area contains numerous large plutons and smaller stocks but also contains many small, shallowly emplaced intrusive bodies, including dikes, sills, and intrusive lava dome complexes. The age, composition, and geographic distribution of intrusions in north-central and northeast Nevada (hereafter, the study area) are summarized by du Bray and Crafford (2007). Intrusive igneous rocks, of multiple ages, are known to be major constituents of the geologic framework in the study area (Stewart and Carlson, 1978). Abundant middle to late Mesozoic and early to middle Cenozoic intrusions in the study area are probably byproducts of subduction-related processes, including back-arc magmatism, that prevailed along the west edge of the North American plate during this interval.
The Igarape Bahia gold mine is located in the Carajds region, Para State, northern Brazil. The area is a typical example ofsupergene gold mineralization related to gossans, where superimposed lateritization processes obliterated their upper horizon and gave rise to new and wider dispersion of gold and of other metals, with meaningful consequences for geological exploration in this environment. An exploration program in this area was carried out by Docegeo, a subsidiary of "Companhia Vale do Rio Doce - CVRD", which is the sponsor of the Carajds mining district and, currently, is also minigfor gold at Igarape Bahia.
