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Редактор(ы):Singh P., Singh V.P., Haritashya U.K.
Издание:Springer, 2011 г., 1253 стр.
Язык(и)Английский
Encyclopedia of Snow, Ice and Glaciers

The earth's cryosphere, which includes snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost, contains about 75% of the earth's fresh water. It exists at almost all latitudes, from the tropics to the poles, and plays a vital role in controlling the global climate system. It also provides direct visible evidence of the effect of climate change, and, therefore, requires proper understanding of its complex dynamics. This encyclopedia mainly focuses on the various aspects of snow, ice and glaciers, but also covers other cryospheric branches, and provides up-to-date information and basic concepts on relevant topics. It includes alphabetically arranged and professionally written, comprehensive and authoritative academic articles by well-known international experts in individual fields. The encyclopedia contains a broad spectrum of topics, ranging from the atmospheric processes responsible for snow formation; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide distribution; glaciation and ice ages; glacier dynamics; glacier surface and subsurface characteristics; geomorphic processes and landscape formation; hydrology and sedimentary systems; permafrost degradation; hazards caused by cryospheric changes; and trends of glacier retreat on the global scale along with the impact of climate change. This book can serve as a source of reference at the undergraduate and graduate level and help to better understand snow, ice and glaciers. It will also be an indispensable tool containing specialized literature for geologists, geographers, climatologists, hydrologists, and water resources engineers; as well as for those who are engaged in the practice of agricultural and civil engineering, earth sciences, environmental sciences and engineering, ecosystem management, and other relevant subjects.

Источник:twirpx
Автор(ы):Гупта Харш К.
Издание:Springer, 2011 г., 1578 стр., ISBN: 978-90-481-8701-0
Язык(и)Английский
Encyclopedia of Solid Earth Geophysics/Энциклопедия по геофизике Земли

Первое издание энциклопедии по геофизике земли было издано в 1989 издательской компанией Вана Ностранда Реинхолда. Более двадцати лет спустя, это новое издание, отредактированное профессором Харшом К. Гупта, представляет полностью пересмотренную и расширенную работу. Энциклопедия объединяет более 200 статей, охватывающих уже установленные и новые концепции геофизики из различных разделов науки, таких как геодезия, геомагнетизм, сейсмология, глубинные земные процессы, тектоника плит, вычислительные методы, и т.д. в систематическом и последовательном формате. Это авторитетный источник информации благодаря вкладу редакторов и авторов со всего света, предназначенный для нынешних и будущих поколений профессионалов.

Редактор(ы):Sigurdsson H.
Издание:Academic Press, 2000 г., 1111 стр.
Язык(и)Английский
Encyclopedia of volcanoes
Издание 2
Редактор(ы):Sigurdsson H.
Издание:Academic Press, 2015 г., 1081 стр.
Язык(и)Английский
Encyclopedia of volcanoes
Издание 2
Автор(ы):Bell F.G.
Издание:Elsevier, 2007 г., 593 стр., ISBN: 978-0-7506-8007-6
Язык(и)Английский
Engineering geology

As noted in the Preface to the first edition, engineering geology can be defined as the application of Geology to engineering practice. In other words, it is concerned with those geological factors that influence the location, design, construction and maintenance of engineering works. Accordingly, it draws on a number of geological disciplines such as geomorphology, structural geology, sedimentology, petrology and stratigraphy. In addition, engineering geology involves hydrogeology and some understanding of rock and soil mechanics.

Similar to the first edition, this edition too is written for undergraduate and post-graduate students of engineering geology. It is hoped that this will also be of value to those involved in the profession, especially at the earlier stages of their careers. However, it is aimed at not just engineering geologists but also at those in civil and mining engineering, water engineering, quarrying and, to a lesser extent, architecture, planning, surveying and building. In other words, those who deal with the ground should know something about it.

Том 26, Выпуск 12
Издание:Journal Geology, 1998 г., 4 стр.
Язык(и)Русский
Eocene magmatism the heat source for Carlin-type gold deposits of northern Nevada

The origin of Carlin-type or sediment-hosted, disseminated gold deposits of the Great Basin, the major source of gold in the United States, is poorly understood. We propose that Eocene magmatism was the heat source that drove the hydrothermal systems that generated these deposits in the Carlin trend and Independence Mountains in northern Nevada. This interpretation is based on a strong spatial and temporal association of Eocene intrusive-volcanic centers with the gold deposits of this region. Our new work and published 40Ar/39Ar dates indicate that magmatism was particularly intense between 39 and 40 Ma throughout northeastern Nevada, especially in and around the area of gold deposits. Carlin-type deposits may have formed preferentially during Eocene magmatism because it was (1) more intense in the area than other magmatic episodes, (2) somehow compositionally distinct, or (3) accompanied by extension that promoted hydrothermal flow. However, large-scale extension does not appear to have been a factor in generating Carlin-type deposits.

Издание:Journal of Geochemical Exploration, 1995 г., 50 стр.
Язык(и)Английский (перевод)
Epithermal gold deposits of the southwest Pacific

Since the freeing of the market price of gold in 1971. exploration for epithermal gold deposits in the southwest Pacific region has been intense, and has been encouraged by some major successes. Sufficient discoveries have been made to summarise what has been found to date, and to assess what implications may be drawn for future exploration. Data are tabulated for 137 epithermal precious metal deposits and prospects in Australia (30), Fiji (2). Indonesia (43 ). New Zealand (22), Palau and Yap (2), Papua New Guinea (18), the Philippines (19), and Solomon Islands (1).

Comparison of the character of epithermal deposits in the southwest Pacific with those in other regions (e.g., the northeastern Pacific margin) suggests that they are in most respects similar with, however, three differences: (i) through much of the region (especially the Philippines and Indonesia) low-sulfidation style deposits commonly show characteristics suggestive of formation at deeper levels than is typical elsewhere; (ii) high-sulfidation deposits appear to be more common than along the northeast Pacific margin; (iii) many of the largest deposits show atypical features, particularly those suggestive of a transition to porphyry or mesothermal conditions, or indicating overprinting of an epithermal system on a porphyry environment. These differences can be partly understood in terms of the tectonic setting and evolution of the volcanic arcs of the southwest Pacific, and the consequent hydrological conditions that existed during mineralization.

The results of exploration in the southwest Pacific indicate that, while the principles of formation of epithermal deposits still apply, deposit models developed in other tectonic/volcanic settings should not be rigidly applied. Gold explorers should first consider the character of the geologic environment at the time of mineralization to try to predict the hydrological conditions during mineralization. Once the likely volcanic environment and paleorelief have been established, then the types, distribution, and zoning of hydrothermal alteration, coupled with observations of deposit form, vein textures and mineralogy, will allow a judgement to be made on the level of system that is now exposed, and on the probable controls that localized mineralization.

The very dynamic character of the tectonic and volcanic setting throughout much of the southwest Pacific has resulted in deposits that reflect changes in the environment of the deposit, in some cases even while deposition was occurring. This has produced some deposits with unusual characteristics which could not have been predicted before exploration.

Издание:PGS Publishing, Linden Park, 2005 г., 19 стр.
Язык(и)Английский
Erdenetiin Ovoo Porphyry Copper-Molybdenum Deposit in Northern Mongolia

Erdenetiin Ovoo, the largest porphyry copper-molybdenum deposit in Mongolia (1.78 Gt @ 0.62% Cu, 0.025% Mo), is exploited by the Erdenet mine. It is located within the Orkhon-Selenge volcano-sedimentary trough which was developed on an active continental margin. The geodynamic evolution of the trough involves an early intra-continental stage, comprising rifting of a shallow continental shelf, accompanied by the emplacement of sub-aerial Permian mafic and felsic, and Triassic mafic volcanics. The Permian volcanics are predominantly alkali-rich trachyandesites, occurring as interlay ered flows and pyroclastics of the Khanui Group, overlying a Vendian (late Neoproterozoic) to early Cambrian basement with Palaeozoic (Devonian) granitoid intrusions, and Carboniferous sediments. Plutons, ranging in composition from diorite to granodiorite, quartz syenite and leucogranite intrude the Permian volcanic succession and exhibit similar compositional trends as the host volcanics. This suggests the intrusions are related to, and possibly coeval with, the volcanic rocks. The Triassic Mogod Formation volcanics, which are largely composed of trachyte flows, trachyandesite and basaltiotrachyandesite, directly overlie the Permian sequence. Early Mesozoic porphyritic subvolcanic and hypabyssal intrusions, which are genetically associated with the trachyandesite volcanics, are related to a continental collisional setting. These include syn-mineral granodiorite-porphyry intrusions which form shallow bodies, occurring as elongated dykes or small, shallow stocks. These porphyries vary from quartz diorite through granodiorite to granite in composition. They are characterised by porphyritic textures (up to 40% phenocrysts) with plagioclase phenocrysts set in a fine-grained groundmass of K feldspar, and are found in the core of the hydrothermal systems, where they are associated with high-grade ore.

Автор(ы):Schneiderhohn H.
Издание:Verlag Von Gustav Fischer, Jena, 1944 г., 290 стр.
Язык(и)Немецкий
Erzlagerstatten. Kurzvorlesungen zur einfuhrung und zur wiederholung

In Besprechungen des „Lehrbuchs der Erzlagerstättenkunde" 1941, Band I und in Zuschriften von Kollegen wurde ich wiederholt aufgefordert, einen kurzen Leitfaden über Erzlagerstätten zu schreiben. Auch beim eigenen Unterricht und besonders bei der Fernbetreuung der in der Wehrmacht eingezogenen Studenten machte sich immer mehr dieser Wunsch bemerkbar. Ich lege nun diesen kurzen Leitfaden vor, der etwa Umfang und Form hat, wie es sich zuletzt in einer zweisemestrigen Kurzvorlesung herausgebildet hatte. Leider gestattete die heute gebotene Knappheit im Umfang die Einschaltung von Abbildungen nicht. Sie hätten in so reichlicher Menge beigegeben werden müssen, daß das Buch dreimal umfangreicher geworden wäre. Es ist beabsichtigt, später einmal einen Atlas zu den Erzlagerstätten gesondert herauszugeben, der zur Illustrierung dieser „KurzVorlesung" dienen soll. Aus demselben Grunde wurde auch auf zusammenhängende Ausführungen über Lagerstättenprovinzen, Metallepochen und ihre Beziehungen zur Geotektonik und zum Geomagmatismus verzichtet, die nur mit vielen Karten verständlich werden. Auch die geochemische Verteilung der Elemente konnte deshalb nicht berücksichtigt werden.

Выпуск 98
Издание:Economic geology, 2003 г., 14 стр.
Язык(и)Английский
Evaluation of Radioisotope Dating of Carlin-Type Deposits in the Great Basin, Western North America, and Implications for Deposit Genesis

A variety of techniques have been used in attempts to date the mineralization in Carlin-type deposits in the Great Basin, with highly variable results. These techniques and results are reviewed in this paper, along with presentation of two new dates, for the Rodeo deposit on the Carlin trend and for the Barneys Canyon deposit in Utah. Complete resetting of sericite by hydrothermal fluids of the temperature and duration of hydrother-mal activity that form Carlin-type deposits is considered highly unlikely. Therefore, dates from sericite are generally of questionable value unless that sericite can be shown to have formed during the same hydrothermal event during which Au was deposited. For the deposits that have been investigated to date, sericite dates rarely, if ever, record the age of Au mineralization. However, sericite ages do appear to record pre-Au events in some districts. Such events may have contributed to ground preparation and, to a much lesser extent, to the tenor of the ore. Fission-track and U/Th-He techniques provide important age constraints on mineralization in some districts but also suffer from a less than clear association with Au. Rb-Sr dating of galkhaite, an Hg sulfosalt, provides the only direct age of mineralization, but galkhaite has been recognized in only a few locations (and dated in only two deposits). In a similar manner, adularia is contemporaneous with Au at Twin Creeks, but Twin Creeks is the only Carlin-type deposit where adularia has been reported. Several other techniques (U-Pb, Re-Os, Sm-Nd) have been used in attempts to date the deposits but with limited success.

2056.36