Mid-ocean ridge basalt composition

Ono S. (1998) Stability limits of hydrous minerals in sediment and mid-ocean ridge basalt compositions implications for water transport in subduction zones. J. Geophys. Res. 103, 18253-18267. 

Estimating the unaltered composition of the oceanic crust is necessary for flux estimates because these estimates are determined as the difference between original and altered compositions. Table 2 displays an average unaltered mid-ocean ridge basalt composition (MORB, Hofmann, 1988) and estimate of an unfractionated MORB composition (Sun and McDonough, 1989), but it is important to emphasize that the... 

Lundstrom CC, Shaw H, Ryerson F, Phinney D, Gill J, Williams Q (1994) Compositional controls on on the partitioning of U, Th, Ba, Pb, Sr and Zr between clinopyroxene and haplobasaltic melts implications for uranium series disequilibria in basalts. Earth Planet Sci Lett 128 407-423 Lnndstrom CC (2003) Uranium-series disequilibria in mid-ocean ridge basalts observations and models of basalt genesis. Rev Mineral Geochem 52 175-214... 

Chlorine isotope compositions vary by up to 15%o (Chapter 7 Stewart and Spivack 2004). These large variations in Cl isotope compositions are found in marine environments, including mid-ocean ridge basalts, seafloor and hydrothermal alteration products, and sedimentary pore... 

Mantle reservoirs. The only quasi-systematic studies of igneous materials have centered on the mantle in particular mid-ocean ridge basalts (MORE), ocean island basalts, and mantle peridotites. After reporting one MORE analysis in Chan and Edmond (1988), the first full study of MORE (Chan et al. 1992) reported three apparently imaltered Atlantic basalts and one from the East Pacific Rise, with a range in 8 Li of +3.4 to +4.7 (Fig. 5). Subsequent studies have increased the global range of samples, the diversity of bulk compositions analyzed. 

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... 

Marty B, Zimmermann L (1999) Volatiles (He, C, N, Ar) in mid-ocean ridge basalts assesment of shallow-level fractionation and characterization of source composition. Geochim Cosmochim Acta 63 3619-3633... 

Fig. 4.8. (A). REE patterns of the Vulsini rocks. The ruled area encloses patterns of mafic rocks. (B) Incompatible element patterns of malic rocks from Vulsini. The pattern of the late erupted Lamone trachybasalt lava is shown in detail. Composition of Enriched Mid Ocean Ridge Basalt (E-MORB Sun and McDonough 1989) is reported for comparison.

Rocks with a composition similar to the Mid-Ocean Ridge Basalts have been recovered from the Vavilov basin (ODP Site 655 and DSDP Site 373)... 

Salters V. J. M. and Dick H. J. B. (2002) Mineralogy of the mid-ocean-ridge basalt source from neodymium isotopic composition of abyssal peridotites. Nature 418, 68-72. 

The mantle is the Earth s largest chemical reservoir comprising 82% of its total volume and 65% of its mass. The mantle constitutes almost all of the silicate Earth, extending from the base of the crust (which comprises only 0.6% of the silicate mass) to the top of the metallic core at 2,900 km depth. The chemical compositions of direct mantle samples such as abyssal perido-tites (Chapter 2.04) and peridotite xenoliths (Chapter 2.05), and of indirect probes of the mantle such as basalts from mid-ocean ridge basalts (MORBs) and ocean island basalts (OIBs) (Chapter 2.03), and some types of primitive... 

Asimow P. D., Hirschmann M. M., and Stolper E. M. (2001) Calculation of peridotite partial melting from thermodynamic models of minerals and melts IV. Adiabatic decompression and the composition and mean properties of mid-ocean ridge basalts. J. Petrol. 42, 963-998. 

Presnall D. C. and Hoover J. D. (1984) Composition and depth of origin of primary mid-ocean ridge basalts. Contrib. Mineral. Petrol. 87, 170—178. 

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