The peculiar properties of zinc oxide (ZnO) make this material interesting for very different applications like light emitting diodes, lasers, and piezoelectric transducers. Most of these applications are based on epitaxial ZnO layers grown on suitable substrates, preferably bulk ZnO. Unfortunately the thermochemical properties of ZnO make the growth of single crystals difficult: the triple poi...

The deepest rocks known from within Earth are fragments of normal mantle ( approximately 400 km) and metamorphosed sediments ( approximately 350 km), both found exhumed in continental collision terranes. Here, we report fragments of a highly reduced deep mantle environment from at least 300 km, perhaps very much more, extracted from chromite of a Tibetan ophiolite. The sample consists, in part,...

[1] Recent spectroscopic detections of CH4 in the atmosphere of Mars are the first definitive observations of an organic compound on that planet. The relatively short photochemical lifetime of CH4 ( 300 years) argues for a geologically young source. We demonstrate here that lowtemperature alteration of basaltic crust by carbon-bearing hydrothermal fluid can produce the required CH4 flux of 1 10...

Hydrogen has been thought to be an important light element in Earth's core due to possible siderophile behavior during core-mantle segregation. We reproduced planetary differentiation conditions using hydrogen contents of 450 to 1500 parts per million (ppm) in the silicate phase, pressures of 5 to 20 GPa, oxygen fugacity varying within IW-3.7 and IW-0.2 (0.2 to 3.7 log units lower than iron-wüs...

Introduction: NWA 5298 is a single 445 g meteorite found near Bir Gandouz, Morocco in March 2008 [1]. This rock has a brown exterior weathered surface instead of a fusion crust and the interior is composed of green mineral grains with interstitial dark patches containing small vesicles and shock melts [1]. This meteorite is classified as a basaltic shergottite [2]. A petrologic study of this Ma...

Oxygen fugacity has been calculated for rutile–ilmenite assemblages from the reaction 2Fe2O3 (in ilmenite) C 4TiO2 (rutile) D 4FeTiO3 (in ilmenite) C O2. The equation log f O2 D 22:59 25925=T 3:09 log T C 0:0016535P C 48:836P=T 4 log a FeTiO3 C 2 log a Fe2O3 C 4 log a TiO2 , where T is in kelvin and P is in kbar, was derived from available thermodynamic data. The hypothetical end-member rutile–...

Several investigations have demonstrated that olivine may be used to simulate geochemical and cosmochemical reactions. Since in extra-terrestrial samples has varying forsterite numbers natural contains inevitable impurities, synthetic with the requisite number been prepared for various experimental research. This study aimed synthesize Fe-bearing via experiments conducted at near-solidus temper...

Introduction: Metal segregation und subsequent formation of an FeNi core is the major differentiation process in large planets such as the earth, but metal separation and aggregation will also occur in smaller planetsimals such as asteroids. Core formation implies partial or full equilibration of core forming FeNi with liquid silicates, implying partial or complete redistribution of siderophile...