Introduction: In Table 1 we have compiled the chemical compositions, including Ni and Co, of representative basalts from Earth, Moon, Mars and Vesta. The SiO2 and MgO concentrations of all basalts cover only a small compositional range, suggesting a similar extent of fractionation. The Ni and Co contents increase with the radius of the planet, with very low concentrations in Vesta and increasin...

The eutectic mineral assemblage calcite-dolomitepericlase-apatite-forsterite-magnesioferrite-pyrrhotite-alabandite in a carbonatite dike within the Oka complex, Quebec, buffers the fugacities (and partial pressures) of all gas species in C-O-H-S-F, assuming vapor saturation. At the inferred eutectic (640 ~ C, 1 kbar), the most important gas species and their partial pressures (bars) were: H20, ...

Introduction: Martian meteorites have various characteristics, which are direct clues to understanding the petrogenesis of Mars rocks. The variation in oxidation state among the Martian meteorites must have important implications for redox conditions of the Martian crust/mantle and overall differentiation on Mars. Wadhwa [1] and Herd et al. [2] reported that Martian basalts were formed under a ...

Mantle oxygen fugacity exerts a primary control on mass exchange between Earth's surface and interior at subduction zones, but the major factors controlling mantle oxygen fugacity (such as volatiles and phase assemblages) and how tectonic cycles drive its secular evolution are still debated. We present integrated measurements of redox-sensitive ratios of oxidized iron to total iron (Fe3+/SigmaF...

Introduction: Oxygen fugacity (fO2) is an important factor in planetary formation and evolution. Certain minerals or assemblages of minerals are stable only under certain fO2 conditions (at a constant T and P) and can be recorders of ambient fO2 during geologic processes. The best estimate of oxygen fugacity from mineral assemblages has implications, from large-scale models of planetary evoluti...

Introduction: Primitive achondrites (IAB irons/winonaites; acapulcoites/lodranites; and brachinites) have chondritic compositions, but nonchondritic textures (from metamorphic through partially melted) [1]. Because of this, they offer a unique insight into the first stages of the differentiation process on asteroids. Acapulcoites and lodranites have textural and mineralogical evidence that they...