Effect of variable CO2on eclogite-derived andesite and lherzolite reaction at 3 GPa-Implications for mantle source characteristics of alkalic ocean island basalts

Major element chemistry of ocean island basalts — Conditions of mantle melting and heterogeneity of mantle source

Episodic entrainment of deep primordial mantle material into ocean island basalts.

Chemical differences between mid-ocean ridge basalts (MORBs) and ocean island basalts (OIBs) provide critical evidence that the Earth's mantle is compositionally heterogeneous. MORBs generally exhibit a relatively low and narrow range of (3)He/(4)He ratios on a global scale, whereas OIBs display larger variability in both time and space. The primordial origin of (3)He in OIBs has motivated hypo...

Continuous eclogite melting and variable refertilisation in upwelling heterogeneous mantle

Large-scale tectonic processes introduce a range of crustal lithologies into the Earth's mantle. These lithologies have been implicated as sources of compositional heterogeneity in mantle-derived magmas. The model being explored here assumes the presence of widely dispersed fragments of residual eclogite (derived from recycled oceanic crust), stretched and stirred by convection in the mantle. H...

effect of bataine and sulphate supplement on wool and milk characteristics and lambs performance in naine ewes

تعداد 20 رأس میش نژاد نائینی 6+-24 ماهه، با میانگین وزن 2/3-+40 کیلوگرم، همراه با 20 رأس بره های آنها در قالب طرح کاملا تصادفی اثر بتائین و مکمل سولفات بر خصوصیات شیر و پشم و عملکرد بره ها بررسی شد. میش ها بطور تصادفی در چهار تیمار قرار گرفتند. تیمارها عبارت بودند از: 1-گروه شاهد 2-بتائین (05/0 درصد ماده خشک) 3-سولفات (24/0 سولفور درصد ماده خشک 4-بتائین هرماه با سولفات. جیره غذائی طبق nrc با مح...

Generation of mid-ocean ridge basalts at pressures from 1 to 7 GPa

We propose a model for the generation of average MORBs based on phase relations in the CaO-MgO-Al2O3-SiO2-CO2 system at pressures from 3 to 7 GPa and in the CaO-MgO-Al2O3-SiO2-Na2OFeO (CMASNF) system at pressures from 0.9 to 1.5 GPa. The MELT seismic tomography (Forsyth et al., 2000) across the East Pacific Rise shows the largest amount of melt centered at 30-km depth and lesser amounts at grea...