We discuss herein the differences both in composition and structure of lithospheric mantle Siberian Platform under kimberlite fields different ages. Having analyzed pyrope garnets from kimberlites ages this study aimed to identify genesis, extent probable causes for evolution within various SP blocks. Acquired results revealed noticeable lithosphere thickness blocks Middle Paleozoic Mesozoic, a...

Young intra-transform lavas erupted as a result of extension within the Garrett Transform Fault on the southern East Pacific Rise, are more porphyritic, less evolved, have lower concentrations of incompatible trace elements, and lower ratios of more incompatible to less incompatible elements (e.g. low K=Ti and La=Sm) compared to lavas from the adjacent East Pacific Rise ridge axis. Sr, Nd and P...

This thesis compiles two distinct studies that both document the control of microstructures on rock seismic properties. The first part deals with the development of crystallographic preferred orientations (CPO) in the uppermost mantle associated with melt/fluid-rock interactions, recorded in peridotites xenoliths from the Japan sea back-arc basin. The microstructural and geochemical characteris...

High-pressure melting experiments on the Homestead L5 ordinary chondrite were performed at 5 GPa in a multi-anvil device over a temperature interval that ranged from near solidus to near liquidus conditions. Near solidus silicate liquids of Homestead have higher CaO/Al2O3 and lower Mg# compared to solidus liquids of terrestrial peridotite (e.g.: KLB-1) at this pressure. The silicate portion of ...

Abstract The composition of spinel lherzolite xenolith KLB-1 from the Kilbourne Hole volcanic crater, United States, which is close to Earth’s primitive mantle, was used for thermodynamic modeling phase relations in Na 2 O–CaO–FeO–MgO–Al O 3 –SiO system (NCFMAS) using Perple_X software package temperature range 900–2000 °C and pressures 0.0001–30 GPa. calculated diagram good agreement with publ...

Thick continental lithosphere (tectosphere) beneath African cratons has been stable for ~2.5 b.y. despite its mechanical interaction with sublithospheric mantle. Water is known to have signifi cant infl uence on mechanical stiffness, and the depletion of water is often considered to be a key to preserving the thick lithosphere. Although water-rich environments indicated by the present water con...