Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
The question of energy use underlies virtually all environmental issues. The harnessing of energy for the manifold needs of industrial civilization has driven economic development, and access to affordable energy has been the key to a better life for people around the world. At the same time the environmental costs of human energy consumption are becoming ever more apparent: oil spills, the scarring of land by mining, air and water pollution, and the threat of global warming from the accumulation of carbon dioxide and other greenhouse gases. Increasingly, maintaining an expanding supply of cheap energy seems to clash with concern for the environmental costs of such expansion. In this part of the book, we explore the background of energy production and energy consumption, and examine the prospects for meeting the energy needs of society while protecting the environment.
Strata-bound Cu- (Ag) deposits, long known as 'Chilean manto-type', occur along the Coastal Cordillera of northern Chile (22°-30°S) hosted by Jurassic and Lower Cretaceous volcanic and volcano-sedimentary rocks. These deposits are typical of the first stage of Andean evolution characterised by an extensional setting of the arc magmatism along the active margin of South America. Strata-bound Cu- (Ag) deposits were formed during two metallogenic epochs in the Late Jurassic and uppermost Early Cretaceous. The mineralisation took place at the time of structurally controlled emplacement of batholiths within the Mesozoic volcanic and sedimentary strata. The volcanic-hosted strata-bound Cu- (Ag) deposits invariably occur distal, but peripheral to coeval batholiths emplaced within tilted Mesozoic strata. The prevalent view that these deposits have an inherent genetic relationship with hydrothermal fluid derivation from subvolcanic stocks and dykes is contended here, because these minor intrusions are largely barren and this hypothesis does not fit well with Sr, Os and Pb isotopic data that call for crustal contribution of these elements. The strata-bound Cu- (Ag) mineralisation appears to be produced by fluids of mixed origin that were mobilised within penneable levels and structural weakness zones of the Mesozoic arc-related volcano-sedimentary sequence during the emplacement of shallow granodioritic batholiths under transtensional regimes. These hydrothermal fluids deposited copper and subordinate silver when reacted with organic matter, pyrite and/or cooled away from their heat sources. Although strata-bound Cu- (Ag) mineralisation took place during the same Cretaceous metallogenic event that formed the magnetite-apatite bodies, and Fe-oxide-Cu-Au deposits along the present Coastal Cordillera, the conceivable relationships with these other types of deposits are hampered by the inconclusive debate about the origin of the Chilean Fe-oxide deposits. However, the available data strongly suggest that the Fe oxide-rich deposits are metasomatic in origin and genetically related to contact zones of Lower Cretaceous dioritic batholiths, whereas the iron-poor volcanic-hosted Cu-(Ag) stratabound deposits constitute distal mineralisation peripheral to Upper Jurassic of Lower Cretaceous granodioritic batholiths.
The copper and molybdenum mineralisation of the Chuquicamata deposit has been known since the 19' century. The deposit is located within the Codelco Norte District in the Andes Ranges of northern Chile, 200 km northeast of the city of Antofagasta. Small miners initially worked the exposed oxidised outcrops and high grade oxide veins that were the surface expression of the deposit, although industrial scale mining did not commence until 1915 with open pit exploitation of the main disseminated oxides. Mining has continued to the present day, currently removing approximately 170 000 tonnes of ore and 400 000 tonnes of waste per day.
The purpose of this book is to show how essential is geology in the planning and development of cities. Town and country planning is now accepted throughout the world as a vital public service, in place of the unorganized and uncontrolled use of land in earlier days. All such planning involves the optimum use of land so that the physical development of cities and regions may best meet the needs of people. The proper use of land—for buildings, for roads, for parks—can be achieved only if the nature of the ground and subsurface conditions is known with certainty. Since the science of geology is concerned with all aspects of the crust of the earth, the use of geological information, and of geological methods to obtain new information about local subsurface conditions, should therefore be an essential part of the physical planning of all cities. <...>
Looking back over a century of geoscience research in the Cordillera is both an inspiring and a humbling exercise. So much has been learned that could not have been imagined in 1899! Other contributions to this volume discuss some of the classic papers in various fields that have led the way to fundamental new insights. In this opening chapter, I prefer to highlight the largely unsung but crucial contributions to the overall research effort that have been made by thousands of faces in the crowd laboring steadily outside the limelight to advance our understanding of Cordilleran geoscience. It is easy to forget that the pacesetting perceptions of the giants among us would be impossible without the information gained, day to day, by uncelebrated colleagues who work assiduously, by their own best lights, to dispel the scientific darkness bit by bit. In our admiration for intellectual leaders, we should always remember that science is the most supremely collegial and collaborative of all human endeavors. They also make their marks who never win an award, but must be content with the plaudits of their own consciences. <...>
The often complex, erratic, and localized nature of gold is a common feature of many vein-style gold deposits. This style of mineralization is often referred to as being nuggety or possessing a high-nugget effect. As a result of these complexities resource estimation is difficult and in general, only Exploration Results can be provided or an Inferred Mineral Resource estimated from surface drilling data alone. Underground development, further drilling, and probably bulk sampling will be required to delineate Indicated and Measured Resources.
Remotely sensed image data is widely used in a range of oceanographic, terrestrial, and atmospheric applications, such as land-cover mapping, environmental modeling and monitoring, and the updating of geographical databases. Hence, the quantized pixel values making up an image may be converted to physical values of radiance and related to some property of the surface being sensed. An example of this approach is the calibration of thermal infrared imagery to produce maps of temperature fields, such as sea surface temperature.
The Genesis and Blue Star sedimentary rock-hosted gold deposits occur within the 40-mile-long Carlin trend and are located in Eureka County, Nevada. The deposits are hosted within the Devonian calcareous Popovich Formation, the siliciclastic Rodeo Creek unit and the siliciclastic Vinini Formation. The host rocks have undergone contact metamorphism, decalcification, silicification, argillization, and supergene oxidation.
Clay, noun. Old English Cladg. A stiff viscous earth. (Blackies Compact Etymological Dictionary. Blackie & Son, London and Glasgow. 1946. War Economy Standard) Clay: The original Indo-European word was 'gloi-" "gli-' from which came "glue' and 'gluten'. In Germanic this became 'klai-; and the Old English 'claeg" became Modern English "clay'. From the same source came "clammy' and the northern England dialect "claggy' all of which describe a similar sticky consistency. (Oxford English Dictionary and Ayto's Dictionary of Word Origins, Bloomsbury, 1999) Clay." from Old Greek yRia, y2oia "'glue" 72ivfl "slime, mucus "" y2oidq "'anything sticky" 'from L-E. base *glei-, *gli- 'to glue, paste stick together. (Klein E. A comprehensive etymological dictionary of the English language. Elsevier, Amsterdam, 1967; Skeat W. An etymological dictionary of the English language.
Oxford University Press, 1961; Mann S.E. An Indo-European comparative dictionary. Buske Verlag, Hamburg, 1987) <...>
This paper is a guide to the X-ray examination of clay minerals; it incorporates background information concerning the principal crystallographic features of clay minerals, and how this is used in the X-ray identification of these minerals, together with laboratory techniques and the application of X-ray diffractometry to the diagnosis of the clay minerals in natural sedimentary materials. <...>
