Magma degassing processes are commonly elucidated by studies of melt inclusions in erupted phenocrysts and measurements of gas discharge at volcanic vents, allied to experimentally constrained models of volatile solubility. Here we develop an alternative experimental approach aimed at directly simulating decompression-driven, closed-system degassing of basaltic magma in equilibrium with an H^C^...

We review recent developments in the study of volcanism and tectonics on Venus. Venus’s crust is basaltic, dry, and probably about 30 km thick. The mantle convects, giving rise to plumes, and has a similar composition and mean temperature (∼1300◦C), but a higher viscosity (∼1020 Pa s), than that of the Earth. Inferred melt generation rates constrain the lithospheric thickness to between 80 and ...

The nature of source rocks of basaltic magmas plays a fundamental role in understanding the composition, structure and evolution of the solid earth. However, identification of source lithology of basalts remains uncertainty. Using a parameterization of multi-decadal melting experiments on a variety of peridotite and pyroxenite, we show here that a parameter called FC3MS value (FeO/CaO-3*MgO/SiO...

[1] The earliest formed crust on a single plate planet such as Mars should be preserved, deeply buried under subsequent surface materials. Mars’ extensive cratering history would have fractured and disrupted the upper layers of this ancient crust. Large impacts occurring late in Martian geologic history would have excavated and exposed this deeply buried material. We report the compositional an...

Despite the abundant evidence for the enrichment of phosphorus during the petrogenesis of natural ferro-basalts, the effect of phosphorus on the physical properties of these melts is poorly understood. The effects of phosphorus on the viscosity, density and redox ratio of a ferro-basaltic melt have been determined experimentally. The viscosity measurements were obtained using the concentric cyl...

The Bushveld Complex in South Africa shows spectacular examples of regional and local magmatic erosion the floor cumulates by new melt batches that replenished evolving magma chamber. Field observations indicate that, at some stratigraphic levels, least, 15–20 m pre-existing cumulates, often nearly monomineralic composition (e.g., anorthosite or orthopyroxenite) were completely removed on a sca...