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THE EARTH

Based on the kind of compounds which occur at certain depths in the earth, the globe can be subdivided into layers (figure 7.1). That certain compounds occur at certain depths is and was to a large extent determined by local temperatures and pressures. [Pg.90]

The separations between the layers as indicated in figure 7.1 are not as clear as shown, but are gradual, which results in a gradual change in density and mineral composition. The thickness of the continental earth s crust or lithosphere (Greek lithos = stone) varies between appr. 20 and appr. 60 km, with an average thickness of appr. 35 km. The elementary composition of the lithosphere is well-known, [Pg.90]

When we assume that the first minerals crystallized from a magma, a liquid rock mass, then the movement of the crystals in the magma will mainly be determined by their densities. Light minerals will rise to the surface, whereas heavy ones will sink. A number of densities of elements are listed in table 7.3 which will give you some idea of the occurrence of the various elements in the different earth layers. Please bear in mind that compounds are and were formed during the transport in magma and that this can lead to drastic changes in density. [Pg.91]

Another factor which determines the presence of minerals at certain depths is the tendency to combine with others or affinity of minerals and elements. Noble gases hardly react with other elements and will, because of their low densities, consequently end up in the atmosphere. Relatively light elements (alkaline and alkaline earth metals) with a strong affinity for oxygen are found in the silicate schaal. Heavy elements which are bound to sulphur or oxgen are situated in the sulphide /oxide scale, or even deeper in the nickel/iron scale. [Pg.91]

SULPHIDE/OXIDE SCALE elements with strong affinity for S, e.g. Cu, Ag, Hg, Pb, Fe [Pg.92]


As discussed in Section 2.0 (Exploration), the earth s crust is part of a dynamic system and movements within the crust are accommodated partly by rock deformation. Like any other material, rocks may react to stress with an elastic, ductile or brittle response, as described in the stress-strain diagram in Figure 5.5. [Pg.81]

Electrical forerunners may be found out as the result of electrical field potential between two points (electrotelluric field on the earth surface) measurement. Usually the background potential is 10 mV and during the earthquake it equals to 70 mV. [Pg.914]

There has been much activity in the shidy of photodissociation of cluster ions, dating back to the 1970s when it was realized that most ions in the earth s lower atmosphere were heavily clustered [7, 35, 36],... [Pg.802]

Associative detaclunent reactions are important in controlling the electron concentration in the earth s mesosphere [75]. Reactions in which more than one neutral product are fonued also occur and are sometunes referred to as reactive detaclunent [76]. [Pg.806]

Interstellar clouds of gases contain mostly H, H2 and He, but the minority species are responsible for the interesting chemistry that takes place, just as in the earth s atmosphere. Interstellar clouds are divided into two... [Pg.819]

Ferguson E E, Fehsenfeid F C and Aibritton D L 1979 ion chemistry of the earth s atmosphere Gas Phase Ion Ghemistry ed M T Bowers (San Diego, CA Academic)... [Pg.827]

For molecules exposed to the intensity of sunlight at the earth s surface this would suggest that the molecule might be excited once in the age of the universe. However, the probability is proportional to the square of the light intensity. For a molecule exposed to a pulsed laser focused to a small spot, the probability of being excited by one pulse may be easily observable by fluorescence excitation or multiphoton ionization teclnhques. [Pg.1146]

Rather different circumstances are encountered when considering THz remote sensing of extraterrestrial sources. The major source of THz opacity in the Earth s atmosphere is water vapour, and from either high, dry mountain sites or from space there are windows in which the background becomes very small. Incoherent instruments which detect the faint emission from astronomical sources can therefore be considerably more sensitive than their laboratory... [Pg.1235]

All static studies at pressures beyond 25 GPa are done with diamond-anvil cells conceived independently by Jamieson [32] and by Weir etal [33]. In these variants of Bridgman s design, the anvils are single-crystal gem-quality diamonds, the hardest known material, truncated with small flat faces (culets) usually less than 0.5 nun in diameter. Diamond anvils with 50 pm diameter or smaller culets can generate pressures to about 500 GPa, the highest static laboratory pressures equivalent to the pressure at the centre of the Earth. [Pg.1958]

Alfe D, Gillan M J and Price G D 2000 Constraints on the composition of the Earth s core from ab initio calculations Nature 405 172-5... [Pg.2233]

Figure B3.3.12. Sulphur atoms in liquid iron at the Earth s core conditions, simnlated by first-principle Car-Parrinello molecular dynamics, (a) Initial conditions, showing a mannally-prepared initial cluster of snlphur atoms, (b) A short tune later, indicating spontaneous dispersal of the snlphur atoms, which mingle with the surroundmg iron atoms. Thanks are dne to D Alfe and M J Gillan for this figure. For fiirtlier details see [210. 211]. Figure B3.3.12. Sulphur atoms in liquid iron at the Earth s core conditions, simnlated by first-principle Car-Parrinello molecular dynamics, (a) Initial conditions, showing a mannally-prepared initial cluster of snlphur atoms, (b) A short tune later, indicating spontaneous dispersal of the snlphur atoms, which mingle with the surroundmg iron atoms. Thanks are dne to D Alfe and M J Gillan for this figure. For fiirtlier details see [210. 211].
Atmospheric corrosion results from a metal s ambient-temperature reaction, with the earth s atmosphere as the corrosive environment. Atmospheric corrosion is electrochemical in nature, but differs from corrosion in aqueous solutions in that the electrochemical reactions occur under very thin layers of electrolyte on the metal surface. This influences the amount of oxygen present on the metal surface, since diffusion of oxygen from the atmosphere/electrolyte solution interface to the solution/metal interface is rapid. Atmospheric corrosion rates of metals are strongly influenced by moisture, temperature and presence of contaminants (e.g., NaCl, SO2,. ..). Hence, significantly different resistances to atmospheric corrosion are observed depending on the geographical location, whether mral, urban or marine. [Pg.2731]

The alkali metals of Group I are found chiefly as the chlorides (in the earth s crust and in sea water), and also as sulphates and carbonates. Lithium occurs as the aluminatesilicate minerals, spodimene and lepidolite. Of the Group II metals (beryllium to barium) beryllium, the rarest, occurs as the aluminatesilicate, beryl-magnesium is found as the carbonate and (with calcium) as the double carbonate dolomite-, calcium, strontium and barium all occur as carbonates, calcium carbonate being very plentiful as limestone. [Pg.122]

Aluminium is not found free but its compounds are so widespread that it is the most abundant metal in the earth s crust. Aluminosilicates such as clay, kaolin (or china clay), mica and feldspar are well known and widely distributed. The oxide. AI2O3. occurs (anhydrous) as corundum and emery, and (hydrated) as bauxite. Cryolite. Na,AlF. (sodium hexafluoroaluminate). is found extensively in Greenland. [Pg.141]

After oxygen, silicon is the most abundant element in the earth s crust, It occurs extensively as the oxide, silica, in various forms, for example, flint, quartz, sand, and as silicates in rocks and clays, but not as the free element, silicon. Silicon is prepared by reduction of silica, Si02- Powdered amorphous silicon can be obtained by heating dry powdered silica with either powdered magnesium or a... [Pg.165]

Carbon dioxide, CO. Carbon dioxide is present in air and escapes from fissures in the earth in volcanic regions and where mineral springs occur. It may be prepared by ... [Pg.180]

Oxygen occurs free in the atmosphere (21% by volume. 23 by weight). The proportion is constant over the earth s surtace it is also constant for many miles upwards, because the turbulence of the atmosphere prevents the tendency for the lighter gases, for example helium, to increase in amount at higher altitudes. [Pg.260]

Water contains 89 % by weight of oxygen, and the outer crust of the earth contains about 47% hence air, earth and sea together contain about 50% by weight of oxygen. [Pg.260]

Titanium is not a rare element it is the most abundant transition metal after iron, and is widely distributed in the earth s surface, mainly as the dioxide TiOj and ilmenite FeTi03. It has become of commercial importance since World War II mainly because of its high strength-weight ratio (use in aircraft, especially supersonic), its... [Pg.369]

Manganese is the third most abundant transition metal, and is widely distributed in the earth s crust. The most important ore is pyrolusite, manganese(IV) oxide. Reduction of this ore by heating with aluminium gives an explosive reaction, and the oxide Mn304 must be used to obtain the metal. The latter is purified by distillation in vacuo just above its melting point (1517 K) the pure metal can also he obtained by electrolysis of aqueous manganese(II) sulphate. [Pg.384]


See other pages where THE EARTH is mentioned: [Pg.304]    [Pg.103]    [Pg.155]    [Pg.155]    [Pg.239]    [Pg.358]    [Pg.358]    [Pg.16]    [Pg.16]    [Pg.73]    [Pg.271]    [Pg.485]    [Pg.816]    [Pg.816]    [Pg.820]    [Pg.1235]    [Pg.1237]    [Pg.1240]    [Pg.1243]    [Pg.1306]    [Pg.1311]    [Pg.1359]    [Pg.2276]    [Pg.2289]    [Pg.2697]    [Pg.2741]    [Pg.111]    [Pg.263]    [Pg.637]    [Pg.650]   


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A SKETCH OF THE CHEMISTRY BEHIND KNOWN CARBON-BASED LIFE ON EARTH

Abundance in the Earth and atmosphere

Abundance of Elements in the Earth’s Crust

Age of the earth

An Unimagined but Very Real Threat to the Earths Stratospheric Ozone

Analysis of the Earths Crust - a Geochemical Task

Applications of the Rare Earths

Astronomical factors in orbit of the Earth

Bands of the Spectrum Usable and Partially Used in Earth Sciences

Beryllium and the Alkaline Earth Metal Amides

Beryllium and the Alkaline-Earth Metals

Box 18-3 Instability of the Earths Climate

Calcium in the Earth

Carbon in the earth s crust

Chemistry of the Earth

Common and Rare in the Earths Crust

Complexes of the Alkaline-Earth Metals

Complexes of the Heavier Alkaline-Earth Metals

Crust of the earth

Crystal structures of the rare-earth metals

Density, Pressure, and Gravity as a Function of Depth within the Earth

Dimensions, and Other Parameters of the Earth

Dissipation of cosmic gases from the Earths atmosphere

Early Evolution of the Earth

Earning Your Salt The Alkali and Alkaline Earth Metals

Earth and the Development of Life

Earth the hydrosphere

Earth with the help of semiconductor sensors

Earths, the rare

Electron-Hole Asymmetry in the Rare-Earth Manganates A Comparative

Element in the earth’s crust

Elemental composition of the earth

Elements in the earths crust

Environments for chemical evolution on the primitive Earth

Evolution of the earth

Ewen agnetic and transport properties of the rare earths

Example Photolysis of Acetaldehyde at the Earths Surface

Eyring, The binary rare earth oxides

FRIENDS OF THE EARTH

Flattening factor for the earth

Formation of the Earth

Gao Polarographic Analysis of the Rare Earths

Gasgnier, The intricate world of rare earth thin films metals, alloys, intermetallics, chemical compounds

Gravitational Field of the Earth

Group 2 (IIA) The Alkaline Earths

Group 2 The Alkaline Earth Metals

Group 2 The Alkaline Earths

Group 2 elements - the alkaline earth metals

Group 2A The Alkaline Earth Metals

Group IIA The Alkaline Earth Metals

Group II—the Alkaline-Earth Metals

Handbook on the Physics and Chemistry of Rare Earths, Vol

How Did the Earths Atmosphere Form

How much do we really know about the early Earth

Human Modification of the Earth System Global Change

Hydrates in the Earth

Infrared Absorption by the Earth

Infrared Absorption by the Earth Atmosphere

Ionic Liquids in the Context of Rare Earth Separation and Utilization

Ionic Triatomic Molecules The Alkaline Earth Halides

J.M. Lopez Nieto, The use of rare-earth-containing zeolite catalysts

METALS COME FROM THE EARTHS LIMITED SUPPLY OF ORES

Magnetic and transport properties of the rare earths

Mass, Dimensions, and other Parameters the Earth

Melting point trend in the binary alkaline earth metal alloys

Mendeleev and the Rare-Earth Crisis

Mineral Processing and Extractive Metallurgy of the Rare Earths

Noble Gases in the Earth

Noble gases from the Earths mantle

Nonradiative Transitions in Rare Earth Ions The Energy-Gap Law

Observed values of global mean RF and equivalent changes in the Earths albedo

Of The Earth

Orbit of the Earth

Ore Deposits of the Rare Earths

Origin and evolution of the Earth

Origin of elements, molecules and the earth

Origins of the Earths Chemical Elements

Oxidation-Reduction Balances of the Earth System

Oxides with the Cubic Rare-Earth Sesquioxide Structure

Philosophy of Using the Cycle Approach to Describe Natural Systems on Earth

Photosynthesis The Basis of Life on Earth

Physical Properties of the Rare Earth Metals

Physical and Chemical Properties of the Rare Earths

Polarographic analysis of the rare earths

Preparation in the Earth Sciences

Pressure, and Gravity as a Function of Depth within the Earth

Prices - Not Just a Question of Metal Content in the Earths Crust

Primordial Noble Gas in the Earth

RADIOGENIC COMPONENTS IN THE BULK EARTH AND ATMOSPHERE

Radiation balance of the Earth

Radiation balance of the Earth-atmosphere system

Rare Elements in the Earths Crust - Compounds and Contents

Rare earth elements and their place in the Periodic Table

Reacting Less Violently The Group 2 Alkaline Earth Metals

Reactions of the Alkali and Alkaline Earth Metals

Salting the Earth Group 1 Elements

Schumann and W. Genthe, Organometallic compounds of the rare earths

Sedimentary Carbonates in the Evolution of Earths Surface Environment

Seeding The Earth with Metals

Shielding of the earths magnetic field

Silicon in the Earth

Silva and V.A. Fassel -ray excited optical luminescence of the rare earths

Silva and V.A. Fassel, X-ray excited optical luminescence of the rare earths

Silva and VA. Fassel, X-ray excited optical luminescence of the rare earths

Solar Irradiance at the Earth

Spectra of helium and the alkaline earth metal atoms

Structure of the Earths Interior

Structure of the Earth’s interior

Sulfur in the Earth

Sundstrdm, Low temperature heat capacity of the rare earth metals

Sundstrom ow temperature heat capacity of the rare earth metals

Sundstrom, Low temperature heat capacity of the rare earth metals

Sunlight on the earth’s surface

Survey of the alkaline-earth metals

THE PLANET EARTH

Ternary Chlorides and Bromides of the Rare-Earth Elements

The Alkaline Earths

The Alkaline-Earth Metals

The Alkaline-Earth Oxides, Sulfides, Selenides, and Tellurides

The Alkaline-earth Metals and Their Compounds

The Ancient Earth

The Earth Moon

The Earth System

The Earth and Its Age

The Earth and its Atmosphere

The Earths Atmosphere

The Earths Atmosphere as a Filter

The Earths crusts

The Earths earliest mantle

The Element Carbon on Earth

The Free-Ion Approach to Rare Earth

The Limitations and Challenges of Understanding Earth Systems

The Natural Balance of Heat on Earth

The Nonadiabatic Effects in Alkaline Earth Atoms

The Not-So-Rare Earths

The Origin of Life on Earth

The Primeval Earth Atmosphere

The Rare Earth Elements and Their Compounds

The Rare Earth Ions

The Rare Earth-Hydrogen Compounds

The Rare-Earth and Actinoid Elements

The Sun-Earth system

The Whole Earth

The absorption and fluorescence spectra of rare earth ions in solution

The absorption andfluorescence spectra of rare earth ions in solution

The beginning of Life on Earth Biochemistry

The cost and availability of rare earth-based corrosion inhibitors

The human problem A changing earth system

The major ice ages in Earth history and when they occurred

The primitive Earth

The rare earth elements

The rare earth metals

The s-Block Elements Alkali and Alkaline Earth Metals

Theory of the Earth

Transparency of the Earths Atmosphere

Trivalent Rare Earth Ions The Dieke Diagram

Uses of the rare earths

Weighed the Earth but Thought He Had Captured Phlogiston in a Bottle

What is the role of life in earths climate system

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