Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
The geological (endogenic and exogenic) processes operating in interior and exterior domains of earth are bringing dynamic changes in the lithospheric and geomorphic terrains of this planet since its origin. The interplay of magmatic, tectonometamorphic and metallogenic processes is continuously evolving new continental and oceanic plates (blocks) enriched with magmatic plume and economic minerals. The diverging and converging margins of these blocks were stressed and formed orogenic mobile belts and mountains.
This example shows the "multi-track" recording of the interval between 11 396 and 11441 feet of a well drilled in 1972 in a dominantly shaly deltaic series with thin sandy and dolomitic crossbedding.
This atlas is intended primarily for anybody who is interested in basic geology of Africa. Its originality lies in the fact that the regional geology of each African nation or territory is reviewed country-wise by maps and text, a view normally not presented in textbooks of regional geology. It is my belief, that there has long been a need in universities and geological surveys, both in Africa and in the developed world, for summarizing geological maps and an accompanying basic text utilising the enormous fund of knowledge that has been accumulated since the beginning of geological research in Africa in the mid–19th century. I hope that, in part, the present atlas may satisfy this need.
Uranium is a trace element in the earth’s crust. Because of its low content and uneven distribution, the abundance of uranium in the earth’s crust varies greatly. The general value is on the order of parts per million (10−6), while the highest value can reach 10−4. Although it may seem that the content of uranium is minor, In fact, it is higher than that of tungsten, mercury, silver, and other familiar metals, being even thousands of times higher than that of gold!
In relation to modern lines of communication it seems surprising that the Gregory Rift Valley was the last part of the system to become known. Much of the earlier exploration had however been centred on the problem of the sources of the Nile, and in consequence the Western or Albertine Rift was explored by Samuel Baker as early as 1862/63 (Baker 1866). Additionally there was a strong tendency to use the convenient base at Zanzibar Island for journeys inland by the Arab slave trading routes from Pangani and Bagamoyo; these led to the Tanganyika Rift and Nyasaland rather than to the area of modern Kenya. The first penetrations into the Gregory Rift area were in I883; Joseph Thomson made an extensive journey into Central Kenya which he described in his book of 1887, 'Through Masai Land' which had as a subtitle, 'a journey of exploration among the snowclad volcanic mountains and strange tribes of Eastern Equatorial Africa--being the narrative of the Royal Geographical Society's Expedition to Mount Kenya and Lake Victoria Nyanza i883-84'.<...>
The Eocene Green River Formation in Wyoming has long served as a standard for lacustrine depositional systems. This lacustrine formation, excluding the culminating phase, was deposited in a closed hydrographic basin. The position of the boundary between lake and mudflat margin was dictated by the inflow evaporation ratio (inflow greater than evaporation = transgression; inflow less than evaporation = regression).
The influence of science and technology on our everyday life and on our society as a whole is immense. Technology advancements are also helping us to generate new opportunities for innovation and growth. The petroleum industry has not remained untouched in this regard. Progressive development of energy resources and their conversion technologies has been bringing benefits to mankind since the mid-18th century, longer than almost any other scientific discipline. In the past decade or so, we have noticed some monumental changes to the energy landscape. Our ability to drill, extract, and produce hydrocarbons from different unconventional resources through technological innovations has played a major role in assisting us to access more affordable energy. <...>
The great surge of interest and activity in exploration for uranium deposits over the last decade has added significantly to our knowledge of uranium geology and the nature of uranium deposits. Much of the information that has been developed by government and industry programmes has not been widely available and in many cases has not had the benefit of systematic gathering, organization and publication. With the current cut-back in uranium exploration and research efforts there is a real danger that much of the knowledge gained will be lost and, with the anticipated resurgence of activities, will again have to be developed, with a consequent loss of time, money and effort. In an effort to gather together the most important information on the types of uranium deposits, a series of reports is being prepared, each covering a specific type of deposit. These reports are a product of the Agency's Working Group on Uranium Geology. This group, which has been active since 1970, has gathered and exchanged information on key questions of uranium geology and co-ordinated investigations on important geological questions. The projects of the Working Group on Uranium Geology and the project leaders are:
Sedimentary Basins and Sandstone Type Deposits — Warren Finch
Uranium Deposits in Proterozoic Quartz-Pebble Conglomerates — Desmond Pretorius
Vein Type Uranium Deposits — Helmut Fuchs
Proterozoic Unconformity and Stratabound Uranium Deposits — John Ferguson
Surficial Deposits — Dennis Toens
The success of the projects is due to the dedication and efforts of the project leaders and their organizations, and the active participation and contribution of world experts on the types of deposits involved. The Agency wishes to extend its thanks to all involved in the projects for their efforts. The reports constitute an important addition to the literature on uranium geology and as such are expected to have a warm reception by the Member States of the Agency and the uranium community, world-wide.
A special word of thanks is extended to Warren Finch for his work in organizing and guiding this project and for editing the text, and to Jim Davis for his participation in the editing of this report on sandstone type uranium deposits.
The Republic of Georgia encompasses pan of the Alpine Himalayan fold belt; it extends from the northern slope of the Greater Caucasus to the Lesser Caucasus in the south, a geologically complex zone sandwiched between two lithospheric plates, the Afro-Arabian (Gondwana) and the Eurasian plates. More specifically it consists of the Greater Caucasus Range
to the north and the Transcaucasus to the south (Fig.l). The sutured boundary (the Sevan-Акега zone) lying between the Transcaucasus and the Lesser Caucasus to the south is effectively the northern margin of Gondwana. The northern boundary, between the Caucasus Mountains (sensu stricto) and the Scythian Platform, the southerly projection of the Russian Platform, is less clearly defined due to the superposition or panial superposition... <...>
Working in the fi eld contributes a crucial element to our knowledge and understanding of Earth processes, whether it is the prediction of volcanic eruptions, understanding periods of past climate change recorded in sedimentary deposits, deciphering an episode of mountain building, or working out where to fi nd mineral resources. Without primary fi eld data and geological samples of the highest quality, further scientifi c study such as sophisticated isotope measurements or the reconstruction of past life assemblages and habitats is at best without context, and at worst, completely meaningless <...>
