Recent studies have reported slight but definite differences in Δ′17O between the lithosphere and hydrosphere. In present study, we precisely accurately quantify values of geothermal H2O mid-ocean ridge basalt (MORB) with normalization on VSMOW-SLAP scale to further substantiate these discuss isotopic evolution hydrosphere throughout geologic time scale. With a value -60 ± 13 × 10-6, MORB is co...

[1] An in-depth Sr-Nd-Pb-He-Os isotope and trace element study of the EMII-defining Samoan hot spot lavas leads to a new working hypothesis for the origin of this high Sr/Sr mantle end-member. Systematics of the Samoan fingerprint include (1) increasing Pb/Pb with time from 18.6 at the older, western volcanoes to 19.4 at the present-day hot spot center, Vailulu’u Seamount, (2) en-echelon arrays...

The late Precambrian Shadli Metavolcanics of SE Egypt constitute a slightly metamorphosed bimodal sequence that has been previously interpreted as manifesting volcanic activity at an island arc. We report the first Rb-Sr geochronologic, trace element (including REE), and Nd isotopic data for these rocks. Two types of basalt are recognized, the stratigraphically lower suite having compositions l...

Seismic studies have found seismic scatterers with -2 to -12% shear velocity anomalies along some subducting slabs at 700-1900 km depth. The ferroelastic post-stishovite transition in subducted mid-ocean ridge basalt (MORB) has been linked these features, but compressional and wave velocities (VP VS) full elastic moduli (Cij) of Al,H-bearing stishovite high pressure remain uncertain. Here we de...

The Spontang Ophiolite complex represents the most complete ophiolite sequence amongst South Ladakh ophiolites and comprises mantle rocks (depleted harzburgites, dunites minor lherzolites) as well crustal (basalt, isotropic gabbros, layered gabbros etc.). In present study, detailed geochemistry (whole rock mineral chemistry) Sr-Nd isotopic analyses of thirty-six ultramafic- mafic samples have b...

Introdução: O carcinoma colorretal (CCR) é a terceira neoplasia com maior incidência no mundo e que mais vezes diagnosticada em Portugal. A sua pode ser controlada através de programas rastreio. plataforma BI-CSP congrega informação diversa relativa à atividade clínica nos cuidados saúde primários presente trabalho teve como objetivo verificar relação entre proporção utentes idade 50-75 anos ra...

Pyroxene is the chief reservoir of Fe 3+ in upper mantle peridotite, but experiments exploring pyroxene/melt partitioning ( D Fe3+ pyx/liq ) have been restricted to 100 kPa and pyroxene with low alumina. Here we present between clinopyroxenes (cpx) mafic melt at elevated pressures (1–2.5 GPa). Experiments were conducted f O2 buffered modulated by Ru + RuO 2 Fe-Pt alloy capsules, respectively, Δ...