We derive an estimate for the chemical composition of the depleted MORB mantle (DMM), the source reservoir to mid-ocean ridge basalts (MORBs), which represents at least 30% the mass of the whole silicate Earth. A database for the chemical and physical properties of abyssal peridotites has become robust and complete enough to truly access a reference DMM. Using trace element depletion trends fro...

We report stable Ni isotope compositions (?60/58Ni, relative to SRM986) for mafic lavas with a range of ?0.16‰ +0.20‰ (n = 44), similar that peridotite samples. Ocean island basalts (OIB) have been analysed from Iceland 6), the Azores 3), Galápagos Islands 2), and L??ihi, Hawaii 1). Samples (average ?60/58Ni +0.13 ± 0.16‰, 2s, n 7) display greatest in single OIB location this work, +0.01‰ +0.23...

Mid-ocean ridge basalts (MORB) reveal large mantle compositional heterogeneity, whose origin remains debated. Here we present a systematic study of molybdenum isotopes on well-characterized MORB glass samples from the East Pacific Rise (EPR) and near-EPR seamounts. Our analyses show significant Mo isotope variations with δ98/95Mo (relative to NIST SRM3134) ranging −0.23‰ −0.06‰. We argue that t...

Abstract We conducted the geochemical modeling of trace element contents for primary melts olivine-phyric rocks from Kamchatsky Mys. This reveals substantial chemical heterogeneity their source while average composition is close to enriched DMM (E-DMM). The estimation melting degree in range 9.1 ± 3.8% model modal batch 15.4 5.2% accumulated fractional melting, which slightly higher than primit...

Soil degradation is a serious environmental issue in many regions of the world, and Sri Lanka not an exception. Maha Oya River Basin (MORB) one major river basins tropical Lanka, which suffers from regular soil erosion degradation. The current study was designed to estimate associated with land use changes MORB. Revised Universal Loss Equation (RUSLE) used calculating annual rates, while Geogra...

1. Begier EM, Frenette K, Barrett NL, et al. A highmorbidity outbreak of methicillin-resistant Staphylococcus aureus among players on a college football team, facilitated by cosmetic body shaving and turf burns. Clin Infect Dis 2004; 39:1446–53. 2. Centers for Disease Control and Prevention. Methicillin-resistant Staphylococcus aureus infections among competitive sports participants—Colorado, I...

A dynamic 3-D spherical-shell model for the chemical evolution of the Earth’s mantle is presented. Chemical differentiation, convection, stirring, and thermal evolution constitute an inseparable dynamic system. Our model is based on the solution of the balance equations of mass, momentum, energy, angular momentum, and four sums of the number of atoms of the pairs U-Pb, U-Pb, Th-Pb, and K-Ar. Si...