Mantle rocks

Wilson TJ (1963) A possible origin of the Hawaian islands. Canad J Phys 41 863-870 Zimmerman ME, Zhang S, Kohlstedt DL, Karato S (1999) Melt distribntion in mantle rocks deformed in shear. Geophys Res Lett 26 1505-1508... 

Based on the following assumptions 50 cm of saturated regolith (mantle rock), 0.5 nr g 1 surface... 

Figure 9. Plots of Li and radiogenic isotopes for mantle rocks, (a) 5 Li vs. Sr/ Sr (b) 5 Li vs. Nd/ Nd (c) "Sr/ Sr vs. Pb/ Pb (d) 5"Li vs. Pb/ Pb (Nishio et al. 2003, 2004). Symbols + = south Pacific island basalts (six islands) O = Iherzolite xenolith, Bullenmerri, Australia = Iherzolite xenolith, Sikhote-Alin, Russia (three localities) A = dunite-peridotite-pyroxenite xenolith, Kyushu, Japan (two localities) V = Iherzolite xenolith, Ichinomegata, Japan. The ocean island data are from bulk rocks, the xenolith data are clinopyroxene separates. For explanations of the derivation of radiogenic isotope fields (DM, EMI, EM2, HIMU), see Zindler and Hart (1986). The estimate for Li isotopes in DM is based on MORE. The Li isotopic ranges for the other mantle reservoirs are based on Nishio et al. (2004) and Nishio et al. (2003), but these will require further examination (hence the use of question marks).

In oceanic fracture zones as well as in actively-upwelling forearc mud volcanoes, seawater or other marine fluids interact directly with mantle rock (Bonatti 1976 Fryer 1985). Serpentinization of mantle rocks at temperatures broadly <350°C involves influx of water, as well as general increase in Li concentration in the newly-formed hydrous assemblage. Considering the low temperatures involved, Li isotope exchange during seawater-mantle... 

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... 

Frey F. A. (1982). Rare earth element abundances in upper mantle rocks. In Rare Earth Element Geochemistry, R Henderson, ed. Elesevier, Amsterdam. 

Modal melting normally does not happen. Due to preferential melting of some minerals in the source rock, x must change. For example, a mantle rock may have 10% cpx, but the cpx may contribute 25% of the melt as a result of preferential melting of cpx, resulting the decrease of as a function of F during melting. 

McDonough, W.F. and Frey, F.A., 1989. Rare earth elements in the upper mantle rocks. 

Even though the lunar crust has been thinned dramatically beneath large impact basins, no exposures of the mantle have been recognized. It is not surprising, then, that no mantle rocks have been found among returned samples. Consequently, the composition of the lunar mantle must be determined indirectly, from the basaltic magmas that represent partial melts of mantle sources. 

Major-element compositions (weight ratios of Mg/Si and Al/Si) for mantle rocks (peridotites) and estimates of the primitive mantle composition of the Earth compared with various groups of chondrites and the Sun. No mixture of chondrite types provides an exact match to the primitive mantle composition, although some carbonaceous chondrites provide the closest match. Modified from Righter et al. (2006). 

Efforts have been made to determine the compositions of both the primitive mantle and depleted materials in the modern mantle. In the approach of Palme and O Neill (2004), the estimated chemistry of the primitive mantle was determined by subtracting the likely elemental concentrations of the Earth s core from results on the bulk chemistry of the Earth. The chemistry of the bulk Earth may be derived from chemical data on Cl chondrite meteorites, spectrographs of the Sun, and/or analyses of upper mantle rocks. Based on the chemical properties of an element, assumptions can be made on how much of the element was likely to have accumulated in the core. On the basis of this approach, Palme and O Neill (2004, 14) concluded that the arsenic concentration of the primitive mantle was 0.066 0.046 mg kg-1 (Table 3.3). 

Soils are a negligibly thin veneer at the interface between the lithosphere and the atmosphere. Productive agricultural soils are only about 0.001 km in depth yet below these soils lie 10-70 km of crustal rocks which, in turn, overlie 2900 km of mantle rocks the equatorial radius of the planet is 6378 km. Human nutrition depends on this thin surface since, while acknowledging the important contribution of fish to human diets, most of our food comes from the land. Sadly, soil is dirt and dirt is despised, but if we do not unterstand the dirt beneath our feet we will not know how to keep this planet healthy for our survival and that of all its other inhabitants. This chapter presents an overview of the composition of soils and its relation to plant nutrition. 

The olivine spinel phase transition Experimental phase equilibrium studies have confirmed deductions from seismic velocity data that below 400 km, olivine and pyroxene, the major constituents of Upper Mantle rocks, are transformed to denser polymorphs with the garnet, y-phase (spinel) and P-phase (wadsleyite) structures (fig. 9.2). In transformations involving olivine to the P- or y-phases, transition pressures... 

Along with studies of melt inclusions, the study of mantle xenoliths (samples of mantle material entrained and brought to the surface in eruption magmas) and exhumed mantle rocks is one of the most common applications of SIMS for trace element analysis. SIMS is ideally suited to this task, as there is no need to try to make mineral separates from what are often limited amounts of sample, alteration can be prevented, and zoning easily studied. 

ChaussidonM., Robert E., Mangin D., Hanon P., and Rose E. E. (1997) Analytical procedures for the measurement of boron isotope compositions by ion microprobe in meteorites and mantle rocks. Geostand. Newslett. 21, 7-17. 

THE COMPOSITION OF THE PRIMITIVE MANTLE BASED ON THE ANALYSIS OF UPPER MANTLE ROCKS... 

Earth s mantle solar model Earth s mantle based on composition of upper mantle rocks ... 

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