The Oldoynio Lengai volcano, Tanzania: the essence of its recent eruptions

2021 ◽  
pp. 60-69
Author(s):  
Alexander BARYSHEV

The article considers the nature of the volcanic fluxes that are traditionally interpreted as the only example of recent mantle-derived carbonatite lavas (carbonate magmas or melts) on the Earth. However, it turns out that this is not correct. These fluxes represent muddy soda masses with organics. Their source are masses of solutions and sediments of the Natron alkaline lake, that penetrate deep to the above-chamber space of the volcano along riftogenic faults, where they are heated and then erupt as fluxes, geysers, and ash masses. The eruption products in turn get to the lake again. At the recent stage of development, the Oldoynio Lengai volcano represents an epimagmatic phreatic hydrothermal recycling system.

1888 ◽  
Vol 9 ◽  
pp. 282-322 ◽  
Author(s):  
J. Henry Middleton

In many respects Delphi and its varied cults possess an interest which is not to be rivalled by that of any other Hellenic site. The lofty precipices, the dark deeply-cleft ravines, the mysterious caves, and the bubbling springs of pure water, combine to give the place a romantic charm and a fearfulness of aspect which no description can adequately depict.Again Delphi stands alone in the catholic multiplicity of the different cults which were there combined.In primitive times it was the awfulness of Nature which impressed itself on the imaginations of the inhabitants.In an early stage of development the mind of man tends to gloomy forms of religion: his ignorance and comparative helplessness tend to fill his brain with spiritual terrors and forebodings. Thus at Delphi the primitive worship was that of the gloomy Earth and her children, the chasm-rending Poseidon, and the Chthonian Dionysus, who, like Osiris, was the victim of the evil powers of Nature. It was not till later times that the bright Phoebus Apollo came to Delphi to slay the earth-born Python, just as the rising sun dissipates the shadows in the depths of the Delphian ravines, or as in the Indian legend the god Indra kills with his bright arrows the great serpent Ahi—symbol of the black thunder-cloud.


An attempt is made to fit available petrochemical data on oceanic volcanic rocks into the structural model for the ocean basins presented by the plate tectonic theory. It is suggested that there are three major volcanic regimes: (i) the low-potassic olivine tholeiite association of the axial zones of the oceanic ridges where magmatic liquids are generated at low pressures high in the mantle, (ii) the alkalic (Na > K) associations along linear fractures where liquids generated at greater depth gain easy egress to the surface, (iii) those alkalic associations, rich in incompatible elements, of island groups, remote from fracture zones, where magmas created at depth proceed slowly to the surface and in consequence suffer intense fractionation. There are certain discrepancies in this pattern, notably that there is no apparent relation between rate of sea-floor spreading and degree of over-saturation of the axial zone basalts and that certain areas, such as Iceland, are characterized by excess volcanism. Explanation of these anomalies is sought by examining an oceanic area in an early stage of development—the Red Sea. It is tentatively suggested that the initial split of a contiguous continent might be brought about by the linking of profound fractures, caused by domal uplift related to rising isolated lithothermal systems, and that the present anomalies in oceanic volcanism may reflect the variation in rate of thermal convection within the original isolated lithothermal plumes.


2021 ◽  
Vol 9 ◽  
Author(s):  
Christine Newville ◽  
Donna L. Whitney ◽  
Patricia Kang ◽  
Natalie H. Raia ◽  
Katherine F. Fornash

Recycling is not just for plastic. Did you know that the Earth recycles? Recycling happens because the outer part of the planet is made up of large moving pieces of rock. Some of these pieces, called tectonic plates, sink deep down into the Earth. The deeper they go, the more heat and pressure they experience. This causes chemical reactions, including melting of the minerals that make up the rocks. Elements and water trapped inside the melting minerals are released and erupt from volcanoes, returning to the surface. The Earth has recycled! In this article, we present new research on a mineral called lawsonite. Lawsonite only forms in plates that dive into the Earth. Lawsonite has returned to the Earth’s surface in a few rare places where we can collect and analyze it. The composition of elements inside the lawsonite mineral help us understand the deep part of the Earth recycling system.


2017 ◽  
Vol 9 (8) ◽  
pp. 179
Author(s):  
Ibrahim Mohammad Khrais ◽  
Ismail Y. Yamin

Economic development occupies a significant status is Islam, as Muslims are commanded to settle and advance the earth. Since anything required to perform a duty is a duty itself, settling the earth can be achieved only by development, which can be achieved by production. The latter builds the earth and assists man in worshipping God.The present paper concentrates on the role of macroeconomics in accomplishing economic development from an Islamic perspective. The Noble Qur’an verses and Hadith traditions are reported from specialists in a bid to provide the sought complete picture.Section One investigates the capitalistic view to solve economic crises, which represent the major obstacle to any stage of development. Section Two defines economic development from an Islamic perspective, as well as the criteria set to solve relevant problems. Section Three explores the obstacles to sustainable development in the Islamic World and proposes solutions to alleviate them.This brief study sheds light on the Islamic approach to (sustainable) development, showing the resulting public economic welfare, which would be definitely reflected on individual well-being.The major conclusion that sustainable development is a comprehensive concept associated with the continuity of economic, Poverty and unemployment are the most crucial obstacles that hinder sustainable development.


2020 ◽  
Vol 29 (3) ◽  
pp. 460-470
Author(s):  
Oksana V. Braslavska ◽  
Iurii O. Kyselov ◽  
Roman M. Rudyi ◽  
Oktiabryna O. Kyseliova ◽  
Iryna O. Udovenko

Science, at all stages of its development has always been in close connection with philosophical thought. Such synthesis is characteristic for any branch of science, including geography. This is related to the spatial content of geographical science, since the category of space itself is philosophical. At the boundary of geography and philosophy there are different scientific disciplines, each of which has its own specificity (geosophy, geophilosophy, etc.). This article deals with philosophical geography in general as the most neutral interpretation of the sphere of knowledge and thought about the deep essence of the terrestrialspace and its landscapes.The purpose of the article is to substantiate the stage of development of philosophical ideas in geography. The works of ancient and medieval authors on natural philosophy, geographical and cosmographic works demonstrate attempts to comprehend the essence of the terrestrial space, to find its rational justification, either in the context of generalization and systematization of known factual material (e.g., Eratosthenes’ sphragides), or for the purpose of filling in knowedge gaps, Crates globe), or when trying to explore the sacral space, which was favoured over Earth, which was treated as a secondary object (e.g., cosmographic study by AlKhwarizmi).The 17th - 19th centuries include the New European stage in the evolution of philosophical ideas in geography. It was then that Oecumene spread to almost all the land of the Earth. By this time, the classical geographic works by B.Varenius, A. von Humboldt and C. Ritter were appearing, whose philosophical content is related either to the conceptual and terminological aspect (as in A. von Humboldt concerning the concept of “landscape”), or with the reliance on a philosophical system (in particular, dialectical idealism) on the basis of geographical research (as by C.Ritter). The concept of geographical determinism of Charles Louis de Montesquieu was also philosophical as was the Genetic Approach in Ethnography by Johann Gottfried Herder. An important prerequisite for the further development of philosophical geography was the emergence of methodological trends of geographical studies in the second half of the 19th century, such as anthropogeography of C. Ritter, F. Ratzel, E. Reclus and chorogeography, perfected by A. Hettner on the basis of the philosophical ideas of I. Kant. Anthropogeographic search indicated the possibility for combining the natural and human in one research object, and the holographic concept acquired the character of a paradigm because of its coverage of the entire set ofobjects on the Earth’s surface which are amenable to spatial analysis. In the second half of the 19th century, geography experienced a methodological crisis related to the differentiation of science and, as a consequence, the threat of its loss of research object. Along with anthropogeography, a synthetic trend arose, which in the first half of the 20th century enabled this methodological crisis to be overcome, the emergence of V. Dokuchaev’s doctrines about the nature zones, L. Berg - about the landscape, A. Grigoriev - about the “physical and geographical” shell, P. Teilhard de Chardin, and V. Vernadsky - about the noosphere.The main feature of the modern stage of the development of philosophical geography is the most harmonious combination of concrete scientific and philosophical foundations, which objectively reflects the dialectical nature of the relation between science and philosophy. Organic continuation of philosophical and geographical exploration is exemplified by modern research in geo-psychohistory, geography of culture, geosophy and a number of other scientific disciplines.


Georesursy ◽  
2019 ◽  
Vol 21 (4) ◽  
pp. 55-62
Author(s):  
Renat Kh. Muslimov

The history of studying the crystalline basement in the Republic of Tatarstan, the state of implementation of the super-deep drilling program is given. The scientific substantiation of the replenishment of exploited oil and oil-gas fields is provided by feeding them with deep hydrocarbons through oil supply channels connecting the deep source of hydrocarbons with sedimentary cover deposits. The crystalline basement is of interest for the search for hydrocarbon deposits, but its role as a transit for replenishing deposits of hydrocarbon sedimentary cover in the process of constant degassing of the Earth is more attractive and justified. To use these processes, a fundamentally new approach to the construction of geological and hydrodynamic models of oil fields is proposed, taking into account the fundamental principles of geological science on the formation and reformation of oil deposits and the deep processes of Earth degassing. Prospects are substantiated for the development of “old” fields that are in long-term development, for the calculation of oil recovery factor taking into account oil entering the reservoir from the depths of the Earth, the need for adjusting methods for calculating and accounting reserves, changing levels of material balance, and scientific and practical suggestions for accounting when calculating reserves and designing the development of fundamental principles of field geology. Further prospects for the introduction of hydrodynamic development methods and their significant expansion due to the opening of the processes of replenishment of sedimentary basin deposits with deep hydrocarbons and the reformation of deposits at a late stage of development are shown.


2019 ◽  
Vol 13 (2) ◽  
pp. 16-24
Author(s):  
V. T. Trofimov ◽  
M. A. Kharkina

Abstract: starting with the works of V.I. Vernadsky, the history of the development of ideas about the interaction of the abiotic spheres of the Earth (upper lithosphere, pedosphere, lower atmosphere and surface hydrosphere) and the living (society, microorganisms, vegetation and land wildlife, hydrobionts (bacterioplankton, phytoplankton, zooplankton, macrobenthos)) is presented. The modern ideas about the content of the concept "ecological functions of abiotic spheres of the Earth", including the resource, geochemical, geophysical and geodynamic, involved in the resource and energy support of life and development of biota, are formulated. Three time stages of formation of the ecological functions of abiotic spheres of the Earth are allocated and characterized. It is shown that at the third technogenic-natural stage of development of these functions, when engineering-ecological surveys are carried out, at local sites, the consequences of technogenesis are leading in the assessment of the current state of ecosystems. The interaction of the lithosphere, pedosphere, surface hydrosphere, Earth's atmosphere with each other and the technosphere is described. The issues of necessity of taking into account perception of ecological functions of the Earth in the code of rules (SP) for engineeringecological surveys and the input of new terminology are considered. It is noted that each ecological function of the abiotic spheres of the Earth is characterized by a large number of indicators of private and complex properties, the study of which has long been mandatory during engineeringecological surveys. The statistics on the composition of the work on the study of the spheres of the Earth in the technical guidance documents of different years on engineering-ecological surveys is adduced. It is stated that in the current SP 47.13330.2016 “Engineering surveys for construction. Main provisions” in terms of engineering-ecological surveys, the vast number of characteristics of ecological functions of the abiotic spheres of the Earth, including the study and evaluation of modern geological processes affecting biota are taken into account. The recommendations on improvement of technical guidance documents for engineering-ecological surveys are formulated.


1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.


1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.


1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.


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