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Издание:PGS Publishing, Linden Park, 2005 г., 18 стр.
Язык(и)Английский
A Tectonic Model for Porphyry Copper-Molybdenum-Gold Deposits in the Eastern Indo-Asian Collision Zone

Two Himalayan porphyry copper-molybdenum-gold belts have been developed in the eastern part of the Himalayan-Tibet orogenic zone related to the collision between the Indian and Asian Plates. Both were accompanied by the emplacement of high-level intracontinental, alkali-rich, potassic felsic magmas which produced a huge Cenozoic belt of potassic igneous rock. The emplacement of these magmas was controlled by large-scale strike-slip fault systems, orientated roughly orthogonal to the of the Indo-Asian continental convergence, which adjusted the collisional strain. The Jomda-Markam-Xiangyun copper-molybdenum belt is the western of the two, developed along a narrow zone following the Nanqian thrust, the Jinshajiang fault system, and the Red River shear zone, whereas the eastern, the Zhongdian-Yanyuan-Yao'an porphyry copper-gold-silver belt, was developed along the western margin of the Yangtze Craton. The ore-bearing porphyries have compositions which include granite, monzogranite, and monzonite, with a small amount of quartz-syenite porphyry. They are distinguished from barren porphyries by their higher Si02 (>63 wt %), lower Y (<20 ppm) and their adakitic magma affinity. All alkali-rich porphyries are relatively enriched in large-ion lithophile elements (K, Rb and Ba) and depleted in high-field strength elements (Nb, Ta, Ti and P) with a wide range of Nb/Y ratios.

Издание:International Association for Gondwana Research, 2002 г., 20 стр.
Язык(и)Английский
A Vendian-Cambrian Island Arc System of the Siberian Continent in Gorny Altai (Russia, Central Asia)

An extended Vendian-Cambrian island-arc system similar to the Izu-Bonin-Mariana type is described in the Gorny Altai terrane at the margin of the Siberian continent.

Three different tectonic stages in the terrane are recognized. (1) A set of ensimatic active margins including subducted oceanic crust of the Paleo-Asian ocean, the Uimen-Lebed primitive island arc, oceanic islands and seamounts: the set of rocks is assumed to be formed in the Vendian. (2) A more evolved island arc comprising calc-alkaline volcanics and granites: a fore-arc trough in Middle-late Cambrian time was filled with disrupted products of pre-Middle Cambrian accretionary wedges and island arcs. (3) Collision of the more evolved island arc with the Siberian continent: folding, metamorphism and intrusion of granites occurred in late Cambrian-early Ordovician time. In the late Paleozoic, the above-mentioned Caledonian accretion-collision structure of the Siberian continent was broken by large-scale strike-slip faults into several segments. This resulted in the formation of a typical mosaic-block structure.

Выпуск 20
Редактор(ы):Osmolska H.
Издание:Panstwowe Wydawnictwo Naukowe, Warszawa, 1975 г., 139 стр.
Язык(и)Английский
Acta paleontologica Polonica. Vol XX

Relatively frequently found, the specimens of Homalonotinae are, in general, poorly preserved and, therefore, they are among the groups of trilobites that have so far been rather insufficiently studied. Since their occurrence is limited to the Llandovery through Middle Devonian, they may serve as a good index fossil. Their paleogeographical and correlative importance in the Upper Silurian and Lower Devonian was discussed separately (Tomczykowa, 1974).

The materials, on which the present paper is based, were collected by the writer in 1956—1958 in the Holy Cross Mts. Most of them, however, come from the boreholes managed by the Geological Institute, that is, from Goldap, Bostow, Ciepielow, Bialopole, Krowie Bagno, Lopiennik, Strzelce IG-2 and Zakrzew IG-3, as well as from the drillings of the Oil Research Survey (Malochwiej and Rozkopaczew boreholes) (Text-fig.  1). <...>

Том 1
Автор(ы):Марфунин А.С.
Издание:Springer-Verlag, Berlin, 1994 г., 550 стр., ISBN: 3-540-57254-6; 0-387-57254-6
Язык(и)Английский
Advanced mineralogy. Composition, structure and properties of mineral matter. Vol 1.

All existing introductory reviews of mineralogy are written according to the same algorithm, sometimes called the "Dana System of Mineralogy". Even modern advanced handbooks, which are certainly necessary, include basic data on minerals and are essentially descriptive. When basic information on the chemistry, structure, optical and physical properties, distinguished features and para-genesis of 200-400 minerals is presented, then there is practically no further space available to include new ideas and concepts based on recent mineral studies.

A possible solution to this dilemma would be to present a book beginning where introductory textbooks end for those already familiar with the elementary concepts. Such a volume would be tailored to specialists in all fields of science and industry, interested in the most recent results in mineralogy.

This approach may be called Advanced Mineralogy. Here, an attempt has been made to survey the current possibilities and aims in mineral matter investigations, including the main characteristics of all the methods, the most important problems and topics of mineralogy, and related studies.

The individual volumes are composed of short, condensed chapters. Each chapter presents in a complete, albeit condensed, form specific problems, methods, theories, and directions of investigations, and estimates their importance and strategic position in science and industry.

Том 2
Автор(ы):Марфунин А.С.
Издание:Springer-Verlag, Berlin, 1994 г., 441 стр., ISBN: 5-540-57255-4; 0-387-57255-4
Язык(и)Английский
Advanced mineralogy. Methods and instrumentations. Results and recent developments. Vol. 2

Changes in the methods of investigation have had a crucial impact on progress in mineralogy. Many important methods have emerged with their own parameters, interpretations, problems, new albeit restricted possibilities and scopes, and with their own instrumentation and measurement tools. Even the aims and contents of the investigations have changed. Two processes can be discerned:

1.  The logical completion of developing and elaborating the methods, i.e. determining all physical principles based on a single, general, multifaceted phenomenon: the interaction of radiation (particles) with matter.

These interactions and hence these methods can be presented schematically by two coordinates. One is energy (or wavelength of radiation) and parts of the electromagnetic spectrum (nuclear, X-ray and electron, UV, visible, IR, microwave, SHF and RF). The other coordinate is represented by the modes of interaction (spectroscopy-absorption, emission, scattering-diffractometry, microscopy). The various intersection points in this system of coordinates have already been determined and elaborated in detail according to theoretical and instrumentational aspects.

Автор(ы):Cooke D.R., Holliday J.R.
Издание:Ore deposit and exploration technology, 2007 г., 19 стр.
Язык(и)Английский
Advances in Geological Models and Exploration Methods for Copper ± Gold Porphyry Deposits

This paper focuses on the relationships between the geological model and exploration techniques for porphyry Cu ± Au deposits, with reference to the discovery record and exploration practices over the past fifteen years. The porphyry model is built on a long record of study dating back to the 1960s which has been gradually refined to encompass differences and complexities in mineralization and hydrothermal alteration assemblages resulting from varying intrusion (‘porphyry’) chemistries, differing wallrock geochemical and structural controls, the upwards zonation into the lithocap environment, and the overprinting effects of deep weathering.

Издание:Sрringer, 2006 г., 262 стр., ISBN: 1402044690, 1402044704
Язык(и)Английский
Advances in the Geological Storage of Carbon Dioxide

This volume organise presentations given by leading international researchers at a NATO Advanced Research Workshop on the state-of-the-art of geological storage of CO
2. The book is divided into 5 parts. Part 1 provides background by describing how human activities are modifying the atmosphere in industrially-active areas in Siberia. Part 2 outlines the innovative idea of using deep permafrost layers as either impermeable boundaries below which CO2 can be injected or as a cooling source for the formation CO2 clathrates. Part 3 describes recent studies conducted on naturally occurring CO2 reservoirs, sites which have the potential to help us understand the possible long-term evolution of CO2 storage sites. Part 4 outlines various industrial-scale applications of CO2 geological storage and shows it to be technically practical, economically feasible and, to date, very safe. Finally Part 5 gives us a view of the future, showing how energy uses are predicted to change over the next 50 years and how the public must be involved in any future decisions regarding climate change abatement.

Источник:twirpx
Издание:СО РАН НИЦ ОИГГМ, Новосибирск, 1993 г., 94 стр., ISBN: 5-7323-1784-6
Язык(и)Английский
Age and chemical composition of the Zhamanshin crater impactites and tektites and comparison with Australasian tektites

ТЬе Zhamanshin impact ci'ater is the only impact crater оп the Earth where impactites, various tektites and microtektites coexist. Тhus the Crater becomes the best object to solve the old tektite puzzle. Published before and new data оп the radiogenic ages and chemistry of the Zhamanshin tektites and Australasian tektites summarized to demonstrate their close genetic relations. ТЬе tektite age-paradox serves as the base evidence in favor of the exstraterrestrial origin of tektites. Тhe petrographical and petrochemical features of tektites demonstrate their most рсоЬаЫе volcanic origin.

Выпуск 94
Издание:Economic geology, 1998 г., 34 стр.
Язык(и)Английский
Age Constraints on Jerritt Canyon and Other Carlin-Type Gold Deposits in the Western United States— Relationship to Mid-Tertiary Extension and Magmatism

Carlin-type gold deposits are difficult to date and a wide range of ages has been reported for individual deposits. Therefore, several methods were employed to constrain the age of the gold deposits in the Jerritt Canyon district. Dated igneous rocks with well-documented crosscutting relationships to ore provided the most reliable constraints. K/Ar and 40Ar/39Ar dates on igneous rocks are as follows: andesite dikes 324 Ma, sericitic alteration in andesite dikes 118 Ma, basalt dikes 40.8 Ma, quartz monzonite dikes 39.2 Ma, and calc-alkaline ignimbrites 43.1 to 40.1 Ma. Of these, only the andesite and basalt dikes are clearly altered and mineralized. The gold deposits are, therefore, younger than the 40.8 Ma basalt dikes. The sericitic alteration in the andesite dikes is unrelated to the gold deposits. A number of dating techniques did not work. K/Ar and 40Ar/39Ar dates on mica from mineralized Ordovician to Devonian sedimentary rocks gave misleading results. The youngest date of 149 Ma from the smallest <0.1-)U,m-size fraction shows that the temperature (120°-260°C) and duration (?) of hydrothermal activity was insufficient to reset preexisting fine-grained micas in the host rocks. The temperature and duration was also insufficient to anneal fission tracks in zircon from Ordovician quartzites as they yield Middle Proterozoic dates in both mineralized and barren samples. Apatites were too small for fission track dating. Hydrothermal sulfides have pronounced crustal osmium isotope signatures (18'Os/188Osinitiai = 0.9-3.6) but did not yield a meaningful isochron due to very low Re and Os concentrations and large analytical uncertainties. Paleomagnetic dating techniques failed because the hydrothermal fluids sulfidized nearly all of the iron in the host rocks leaving no remnant magnetism.

Издание:PGS Publishing, Linden Park, 2002 г., 12 стр.
Язык(и)Английский
Alemao copper-gold (U-REE) deposits, Carajas, Brazil

The Alemao copper-gold deposit is located within the Carajas Mineral Province of Northern Brazil and was discovered in 1996 by DOCEGEO using geophysical and geological techniques. Alemao is hosted by the Igarape Bahia Group, which comprises two lithological and stratigraphic domains: a lower metavolcanic unit composed of metavolcanic rocks and acid to intermediate volcanoclastics; and an upper clastic-chemical metasedimentary unit with volcanoclastic rocks. The Alemao ore body is covered by a 250 metres thick unconfonnable siliciclastic unit referred as the Aguas Claras Formation. The ore body, which is 500 metres in length and 50 to 200 metres wide, strikes NE-SW and dips steeply to the NW, being emplaced along the contact between the two stratigraphic domains of the Igarape Bahia Group. In the ore zone, the hydrothermal paragenesis is marked by ferric minerals (magnetite-hematite), sulphides (chalcopyrite, pyrite), chlorite, carbonate (siderite, calcite, ankerite) and biotite, with minor quartz, tourmaline, fluorite, apatite, uraninite, gold and silver. Sericite and albite are rare. The mineralisation is represented by hydrothermal breccias and "hydrothermalites" classified into two types: (1) the BMS type, composed of massive bands of magnetite and chalcopyrite and by polymitic breccias with a matrix comprising magnetite, chalcopyrite, siderite, chlorite, biotite and amphiboles; (2) the BCLS type breccia which comprises brecciated hydrothermalised volcanic rocks with chalcopyrite, bornite, pyrite, chlorite, siderite, ankerite, tourmaline and molybdenite in the matrix, as well as dissemination in the rock. The geochemical association of Fe-Cu-Au-U-REE in iron rich, heterolithic, hydrothermal breccias at the Alemao Cu-Au Deposit, as well as its possible association with an extensional tectonic setting, suggests a correlation with Olympic Dam type mineralization. The total estimated ore resources based on a krigging method is 170 Mt @ 1.5% Cu and 0.8g/tAu.

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