Iron basaltic

The earliest record of human usage of iron dates to ca 2000 BC (5) in Egypt, Asia Minor, Assyria, China, and India. It is almost certain, however, that the first iron to be used was not processed but was obtained from meteorites (1). One of the few places where native iron is found is in Greenland, where it occurs as very small grains or nodules in basalt (an iron-bearing igneous rock) that empted through beds of coal. 

Barzahlung, /. cash payment, bas., abbrev. (basisch) basic, basaltahnlich, a. basaltoid, basaltic. Basalt-eisenerz, n. basaltic iron ore. -felsen, m. basaltic rock, basallfdrmig, a. basaltiform. 

In Fig. 1.85 iron contents of epidote from two different geologic environments, island arc and oceanic ridge or ophiolite, are summarized. It can be seen in Fig. 1.85 that the iron content of epidote from ridge basalt and ophiolite is generally lower than... 

Basalt at middle Miocene age erupted at Northeast Japan was studied by Shuto (1989) and Tsuchiya (1988, 1989) who showed that basaltic magma generated in deep mantle. Dudas et al. (1983) showed that pre-Kuroko ore basalt in the Hokuroku district has Mg number (MgO/(MgO + FeO )), where FeO is total iron content expressed as FeO, in the range 0.85-0.67 0.01, suggesting that the basalt is a relatively primitive, unfractionated, and mantle-derived melt. 

Fig. 2.43. Graphical illustration of sulfur isotope values of HiS (left axis and. solid line) produced during basalt-seawater interaction at various water/rock ratios. Calculations assume that seawater sulfate is mostly removed as anhydrite, that any residual sulfate is reduced by iron oxidation in reacting basalt, and that there is quantitative leaching of basaltic sulfide and homogeneous mixing of both sulfides. Dashed line...

The main alteration minerals surrounding Kuroko ore body are K-mica, K-feldspar, kaolinite, albite, chlorite, quartz, gypsum, anhydrite, and carbonates (dolomite, calcite, magnesite-siderite solid solution), hematite, pyrite and magnetite. Epidote is rarely found in the altered basalt (Shikazono et al., 1995). It contains higher amounts of ferrous iron (Fe203 content) than that from midoceanic ridges (Shikazono, 1984). 

Basalt, granite, manganese nodules, shale, flint clay, iron formation materials, phosphate rock, fertilizers Calcareous loam soil, loess, polluted farmland soil, sand soil... 

Fig. 3.23 Left-. Calculated relationship between the thickness of an alteration rind and/or dust coating on a rock and the amount of 15.0-keV radiation absorbed in the rind/coating for densities of 0.4, 2.4, and 4.0 g cm [57]. The bulk chemical composition of basaltic rock was used in the calculations, and the 15.0 keV energy is approximately the energy of the 14.4 keV y-ray used in the Mossbauer experiment. The stippled area between densities of 2.4 and 4.0 g cm is the region for dry bulk densities of terrestrial andesitic and basaltic rocks [58]. The stippled area between densities of 0.1 and 0.4 g cm approximates the range of densities possible for Martian dust. The density of 0.1 g cm is the density of basaltic dust deposited by air fall in laboratory experiments [59]. Right Measured spectra obtained on layered laboratory samples and the corresponding simulated spectra, from top to bottom 14.4 keV measured (m) 14.4 keV simulated (s) 6.4 keV measured (m) and 6.4 keV simulated (s). All measurements were performed at room temperature. Zero velocity is referenced with respect to metallic iron foil. Simulation was performed using a Monte Carlo-based program (see [56])...

The Se/ Se ratios of CDT and 3 other iron meteorite samples were determined by Rouxel et al. (2002). CDT had the greatest ratio, and the other meteorites ranged from -0.2%o to -0.6%o relative to CDT. Four basaltic reference materials, two glassy MORB s, and one peridotite also analyzed by Rouxel et al. (2002) were within 0.2%o of CDT. These results suggest that the earth s mantle is close in Se isotope composition to CDT, and that CDT is, tentatively, a reasonable proxy for the bulk composition of the earth. 

Edwards R, Sedwick PN, Morgan V, Boutron CF, Hong S (1998) Iron in ice cores from Law Dome, east Antarctica implications for past deposition of aerosol iron. Ann Glaciol 27 365-370 Filer JM (2001) Oxygen isotope variations of basaltic lavas and upper mantle rocks. Rev Mineral Geochem 43 319-364... 

Williams H, Lee D-C, Levasseur S, Teutsch N, Poitrasson R, Halliday AN (2002) Iron isotope composition of mid-ocean ridge basalts and mantle peridotites. Geochim Cosmochim Acta 66 A838... 

An astonishing recent discovery is that there are bacteria living deep in the Earth s crust. Colonies of anaerobic bacteria have been isolated from boreholes 1,500 m deep in basaltic rock formations. The bacteria use H2 as electron donor, which may originate from fermentation of organic matter, or from a purely inorganic reaction of iron of the Earth s core with water (Stevens and McKinley 1995 Anderson et al. 1998). 

Aphyric to sparsely feldspar-phyric rhyolite flows, associated breccias and related hyalotuffaceous sedimentary rocks of the FLB Formation, and basaltic and related sedimentary rocks of the LR Formation immediately overlie the exhalitive (sulfides and iron-formation) horizon of the Key Anacon East and the Key Anacon Main Zones, respectively (van Staai etal. 2003). 

The physical and chemical parameters which influence iron oxide formation vary with time and space, e. g. through changing water/air content. Microenvironments exist in pores of different sizes and with different degrees of filling. For example, hematite was identified in coatings at the (dry) surface of a basalt boulder, whereas goethite occurred in a nearby (moister) crack (Bender-Koch et al., 1995 a). In another case, goethite was the dominant oxide next to the root surface, whereas lepidocrocite predominated a few mm away from it (Schwertmann Fitzpatrick, 1977). Often, however, the exact conditions under which Fe oxides form are difficult to determine. 

Vistisen, L. (1995a) Iron-containing weathering products of basalt in a cold, dry climate. 

Society of Edinburgh that lie had discovered soda in several varieties of Scottish whinstone and m lava from Mt, Aetna (25). He used the term whinstone to include basalt, trap, and certain kinds of porphyry, wacke, and other argillaceous stones. When he analyzed a specimen which had been broken from one of the famous basaltic columns of Staffa, he found that the sum of the earths, silica, and iron never amounted to more than 94 per cent. Suspecting the presence of an alkali, he heated the pulverized mineral with pure sulfuric acid and extracted a salt which he identified as sodium sulfate (25). He proved, moreover, that the sodium compounds had not been dissolved from his glass apparatus. Dr. Kennedy also found 4 per cent of soda in a specimen of lava brought to him by Sir James Hall and Dr. James Home from the famous current of Mt. Aetna which in 1669 had destroyed part of the town of Catania. He published these analyses in 1800 in Nicholsons Journal (25). 

Stony irons are nonchondritic meteorites that contain roughly equal proportions of silicate minerals and metal. Two types of stony irons - pallasites and mesosiderites - are distinguished. Pallasites consist of approximately equal amounts of metal and olivine (one small group contains pyroxene as well). Mesosiderates also have approximately equal proportions of metal and silicate, but the silicate fraction is basalt. 

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