The initial ratios of neodymium-143 to neodymium-144 in kimberlites ranging in age between 90 x 10(6) to 1300 x 10(6) years from South Africa, India, and the United States are different from the corresponding ratios in the minerals of peridotite inclusions in the kimberlites but are identical to the ratios in the basaltic achondrite Juvinas at the times of emplacement of the respective kimberli...

Today, it is known that the majority of diamonds are crystallized mostly from a metasomatic agent close in main characteristics to carbonatite melts acting upon mantle rocks, and therefore, located interstitial space these rocks. So far, diamond has never been found included other kimberlitic or xenolithic minerals. We have inclusion inside olivine grain, which first find its kind. The crystal ...

[1] We report some of the first noble gas data for in situ lower oceanic crust and shallow mantle. From a suite of gabbros and peridotites recovered from the Atlantis Bank oceanic core complex on the Southwest Indian Ridge, we measured He, Ne, Ar, Kr and Xe concentrations as well as He/He and Ar/Ar ratios, there by documenting the noble gas content and signature of oceanic lithosphere. Except f...

Abstract Extensive carbonation of peridotite results in listvenite, a rock composed magnesite and quartz. At Gråberget, Røros, SE-Norway, variably serpentinized body, surrounded by the Røros schists, former abyssal sediment displays all stages transformation to quartzite. In this paper we record sequence steps process combining observation mineral assemblages, textural relationships geochemistr...

[1] Faulting and brittle deformation of mantle rocks occurs in many tectonic settings such as oceanic transform faults, oceanic detachment faults, subduction zones, and continental rifts. However, few data exist that directly explore the frictional properties of peridotite rocks. Improved constraints on the brittle deformation of peridotite is important for a more complete understanding of the ...

This experimental study examines the mineral/ melt partitioning of incompatible trace elements among high-Ca clinopyroxene, garnet, and hydrous silicate melt at upper mantle pressure and temperature conditions. Experiments were performed at pressures of 1.2 and 1.6 GPa and temperatures of 1,185 to 1,370 C. Experimentally produced silicate melts contain up to 6.3 wt% dissolved H2O, and are satur...