Abstract The phenomena of reactive percolation enriched asthenospheric melts and pervasive melt-rock interactions at mid oceanic ridge-rift systems are the principal proponents for mantle refertilization compositional heterogeneity. This study presents new mineralogical geochemical data abyssal peridotites exposed along Vema Vityaz fracture zones Central Indian Ridge (CIR) to address factors co...

The isotopic data showed that there are two stages distinguished in the Cenozoic history of Darkhad depression volcanic activity, Late Oligocene initial stage (~28.0–26.6 Ma) and final Miocene – Early Pliocene (~5.8–4.2 Ma). It has been stated rocks only represented by trachybasalts; however, among final-stage basaltoids series shield-volcano hawaite-basanite-phonotephrite compex trachybasaltic...

The spatial and temporal variability of chemical signals in lavas, residues and melt inclusions provides important constraints on source heterogeneity, the efficiency of convection, and melt transport processes in the mantle. The past decade has seen an impressive increase in the number, precision and spatial resolution of chemical analyses. However, as resolution has increased, the picture of ...

An electron microprobe study has been carried out on platinum-group minerals, accessory phases, and chromite in several chromite deposits of the Alapaevsk ophiolite (Central Urals, Russia) namely the Bakanov Kluch, Kurmanovskoe, Lesnoe, 3-d Podyony Rudnik, Bol’shaya Kruglyshka, and Krest deposits. These deposits occur in partially to totally serpentinized peridotites. The microprobe data shows ...

In order to understand the effects of contractional and extensional tectonics on thick, mantle roots, we have undertaken a systematic study of mantle xenoliths from the Labait volcano, which lies within the East African Rift on the eastern boundary of the Archean Tanzanian craton. The Re-Os systematics of the Labait xenoliths show that ancient, refractory lithosphere is present to depths of ;14...

introduction khoy ophiolite at the global scale is in the middle part of the alp-himalaya orogenic belt and it is extended over 3900 km2 which indicates remnant neotethys oceanic lithosphere in the mesozoic era (kananian et al., 2010). in this paper, in addition to a review of previous investigations about khoy ophiolite, we will try to determine the nature and kind of minerals, origin and part...

Introduction: Martian (SNC) meteorites are igneous rocks from young (except for ALH 84001, which is much older), thick lava flows or shallow intrusions [1]. The shergottites (‘S’ of SNC) can be categorized according to LREE depletion into highly, moderately, and slightly depleted groups [1]. The La/Lu ratio (and other depletion indicators) is positively correlated with oxygen fugacity, and this...

24 25 Cenozoic alkaline lavas from the Al Ashkharah area, facing the Indian ocean along 26 the North-East Oman coastline, contain numerous small (‹ 2cm) mantle xenoliths. 27 They provide a unique opportunity to investigate the nature and evolution of the 28 upper mantle beneath the Oman passive margin, bordering the Owen Basin. All 29 studied xenoliths are porphyroclastic to equigranular spinel...