Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
Magnetism is one of the most pervasive features of the Universe, with planets, stars and entire galaxies all having associated magnetic fields. All of these fields are generated by the motion of electrically conducting fluids, via the so-called dynamo effect. The basics of this effect are almost trivial to explain: moving an electrical conductor through a magnetic field induces an emf (Faraday’s law), which generates electric currents (Ohm’s law), which have associated magnetic fields (Ampere’s law). The hope is then that with the right combination of flows and fields the induced field will reinforce the original field, leading to (exponential) field amplification <...>
The approximately 1000 Mt @ 0.6% Cu, 0.3-0.4 g/t Au Majdanpek porphyry copper is the most northerly deposit within the Timok Magmatic Complex (TMC) which also hosts the exploited Bor and producing Veliki Krivelj deposits. Slightly older, but similar magmatic rocks southeast of the region host the significant porphyry-high sulphidation mineralisation at Elatsite and Chelopech in neighbouring Bulgaria. Similar porphyry deposits are also known in Romania, across the Danube river to the north of Majdanpek. The TMC igneous rocks show clear evidence of crustal contamination and thus likely relate to an eastward dipping subduction zone beneath a continental margin located to the west. Mineralisation is related to sparse and narrow north-south trending andesitic dykes dated at 83 Ma. These dykes intrude along a north-south trending fracture zone cutting Proterozoic and Palaeozoic metamorphic rocks, and Jurassic limestones. Extrusive facies of the TMC are rare at Majdanpek, although they are common farther to the south of the region. Mineralisation is typicaly developed as stockworks, the bulk of which are actually within the metamorphic aureole of the andesitic dykes. There are also numerous skarns and replacement bodies flanking the intrusives, while more distal replacement bodies are found in the Jurassic limestones. The highest copper grades relate to K-silicate alteration and zones of strong silicification. Mo grades are very low throughout the deposit, while the Cu%;Au g/t ratio is approximately 2:1. PGEs occur as minor phases accompanying the copper mineralisation and are recovered at the smelter. Significant supergene upgrading is recorded in an oxidation blanket that was 25 m thick in the north and covered the deposit.
Geotechnical engineering differs from other forms of engineering by the composition of ground, which is composed of a wide range of solids with discontinuities, pores fluids and structures. These different elements composing the ground interact with one another increasing the complexity of any prediction. In traditional geotechnical analysis, limit equilibrium methods (LEM) are useful techniques for estimating the onset of failure.
This book derives from the Integrated Basin Studies Project (IBS), which ran during the years 1992-1995 with the support of the European Commission DGXII. The papers produced by the IBS group have been complemented by eight papers arising from the conference 'Mediterranean Basins: Tertiary Extension within the Alpine Orogen', held in Cergy-Pontoise, France, 11-13 December 1996. The title of this conference has also been retained as the title of the book. The papers included here collectively cover the majority of the Mediterranean Tertiary extensional basins, with the exception of those in the SW of the region. <...>
It is an old wisdom that metals are indispensable for life. Indeed, several of them, like sodium, potassium, and calcium, are easily discovered in living matter. However, the role of metals and their impact on life remained largely hidden until inorganic chemistry and coordination chemistry experienced a pronounced revival in the 1950s. The experimental and theoretical tools created in this period and their application to biochemical problems led to the development of the field or discipline now known as Bioinorganic Chemistry, Inorganic Biochemistry, or more recently also often addressed as Biological Inorganic Chemistry.
By 1970 Bioinorganic Chemistry was established and further promoted by the book series Metal Ions in Biological Systems founded in 1973 (edited by H.S., who was soon joined by A.S.) and published by Marcel Dekker, Inc., New York, for more than 30 years. After this company ceased to be a family endeavor and its acquisition by another company, we decided, after having edited 44 volumes of the MIBS series (the last two together with R.K.O.S.) to launch a new and broader minded series to cover today’s needs in the Life Sciences. Therefore, the Sigels new series is entitled <...>
It is a daunting task for any geologist to understand gold genesis and to find exploration guidelines in the enormous volume of literature. From the perspective of the exploration geologist, this is worth tackling because there is still a large dichotomy when it comes to their genesis, epigenetic-structural aspects and syngenetic concepts. While the targets will not change with the model (Colvine et al., 1984), a better overall understanding will clearly aid target selection and exploration techniques <...>
The promise of the Spacefaring Age - the era of human activities in space - is that it will link human expertise to the unlimited resources of space. When that linkage is established, the people of Earth will be supplied with an abundance of energy and material resources from space; the solar system will be explored in depth; human settlements will be established on multiple planets and moons; and voyages to the stars will be undertaken. The present “closed Earth” mindset - of limits to human potential related to the depletion of Earth’s resources and the vital need to preserve Earth’s environment - will be replaced by a much grander “open space’’ vision of broad-scale human advancements based upon access to unlimited resources and the opening of endless frontiers. <...>
This paper presents new petrological and geochronological data for the ~3.09-2.92 Ga Murchison Greenstone Belt (MGB), located in South Africa’s Kaapvaal Craton, and discusses their geotectonic implications. The MGB is made of three tectono-metamorphic units: the Silwana Amphibolites, the Murchison Unit and the La France Formation. They underwent contrasting clockwise pressure temperature-deformation (P-T-D) histories, and are separated from each other by relatively narrow, high strain shear zones, with a sinistral, transpressive top-to-the-south movement, consistent with the deformation patterns observed throughout the belt.
The National Public Reporting of Exploration Results, Mineral Resources and Mineral Reserves Code of Türkiye (the UMREK Code) designates the minimum standards, recommendations, legal requirements and practice principles for reporting Exploration Targets, Exploration Results, Mineral Resources and Mineral Reserves within the Republic of Türkiye with the purpose of adequately informing investors and other stakeholders. This Code is related to the public reporting related to Exploration Results, Mineral Resources and Mineral Reserves required by BİST, BDDK and SPK (see the list of acronyms in Appendix 12).
Unprecedented population increases have occurred since World War II. mostly in those countries with low agricultural productivity and low per capita incomes. Population growth coupled with rising energy costs and worldwide inflation has taxed the ability of farmers to meet human food requirements. In fact, in some areas. such as sub-Saharan Africa. the per capita food production has actually declined in the past decade.
