The Southwest Indian Ridge (SWIR) at 9^168E and 52^538S is characterized by ultra-slow, oblique spreading and contains one of the few documented occurrences of pyroxenite veins associated with abyssal peridotites. The origin of these uncommon lithologies is still debated.We present a detailed study (including electron microprobe and laser ablation inductively coupled plasma mass spectrometry) o...

Oceanic basalts, such as mid-ocean ridge basalts (MORB) and ocean island basalts (OIB), are characterized by large isotopic and trace element variability that is hard to reconcile with partial melting of a peridotitic mantle alone. Their variability has been attributed to the presence of heterogeneities within the mantle, such as recycled crust, metasomatized material or outer core contribution...

Geochemistry and fluid inclusions studies were carried out on garnet and beryl from Quaternary alluvium deposits of Meluli-Namuhuca area, Mozambique. Garnet occurs as euhedral large crystals and is commonly brownish red, with a moderate brown hue in transmitted light. Apatite and ilmenite are the common inclusions. Geochemically, garnet is characterized by nearly homogenous chemical composition...

Redox chemistry of the coupled atmosphere–hydrosphere system has coevolved with the biosphere, from global anoxia in the Archean to an oxygenated Proterozoic surface environment. However, to trace these changes to the very beginning of the rock record presents special challenges. All known Eoarchean ( c . 3850–3600 Ma) volcanosedimentary successions (i.e. supracrustal rocks) are restricted to h...

A Li-rich majoritic garnet (LiMGt), (Li2Mg)Si2(SiO4)3, was synthesized at 15 GPa and 1500 °C and its structure studied with single-crystal X-ray diffraction and Raman spectroscopy. It is cubic with space group Ia3d and unit-cell parameters a = 11.2660(2) Å and V = 1429.91(1) Å3. The 8-, 6-, and 4-coordinated cation sites in LiMGt are occupied by (Li+ + Mg2+), Si4+, and Si4+, respectively. Where...

During the COUIX of I :50 000 scale regional mapping in the Northern Selkirk Mountains (NTS 082M) various granitic rocks were sampled for U-Pb geochronology. This report presents new U-Pb data, interpreted ages, and the implications of these results for hvo such samples from the Selkirk Allochthon: the Downie Creek otihogneiss, and the Goldstream Pluto”. The Downie Creek orthogneiss consists of...

Textural, major element and trace element data for xeno-liths from Salt Lake Crater, Hawaii indicate that typical four phase lherzolite inclusions (olivine, orthopyroxene, chrome diopside and spinel) found worldwide in basalts are not samples of primitive upper mantle. Rather, lherzolite may be the recrystallized residue left after a basaltic melt extracts the easily fused components from pre-e...

BACKGROUND This study aims to evaluate the efficacy of Er,Cr:YSGG laser assisted periodontal therapy on the reduction of oral malodor and periodontal disease. METHODS Sixty patients with chronic periodontitis were included in the study and allocated into two groups each containing 30 patients. The study was planned in a double blind fashion. Conventional periodontal therapy was performed in g...

background dentin sensitivity is one of the most important problems in dentistry. enamel loss due to root exposure is serious issue and common exposure is one of the reasons for dentin hypersensitivity. there are different methods for solving this problem. one of the most conservative and least expensive methods is use of casein phosphopeptide-amorphous calcium phosphate (cpp-acp) paste. object...

introduction: corticotomy-facilitated orthodontics provides a means for rapidly moving teeth purportedly with little damaging effects to the periodontium and with greatly reduced treatment time. the aim of this study was to enhance the orthodontic tooth movement by reducing the cortical bone layer (resistant to bone re-sorption relative to spongious bone) following erbium, chromium doped yttriu...