The P-T-X dependent water and carbon dioxide saturation in silicate melts of virtually any composition

Volatile components, especially water and carbon dioxide, play a controlling role on practically any process and any property related to magmas and their dynamics, influencing to a first order volcanic eruptions and their related hazards. Consequently, knowing the partitioning of water and carbon dioxide among silicate melts and coexisting gas phases is one major objective in a variety of disciplines such as petrology, rock and fluid geochemistry, and magma and volcano physics and dynamics. Here I present the most updated, most comprehensive model of water and carbon dioxide solubility and saturation in silicate melts of virtually any composition spanning from two-component metal slags to natural magmas from the most iron and magnesium –rich, silica under-saturated, to the most chemically evolved ones found on Earth, the Moon, or Mars. The model rests on rigorous thermodynamic modelling, and on a robust calibration involving nearly 2000 individual saturation data – the entire set of appropriate existing data to my knowledge. Pressure and temperature of calibration also span wide ranges from one bar to several GPa, and from just above liquidus to above 2000 °C, respectively. I show here the capability of the model to properly account for virtually any aspect previously described from the experiments and related to the compositional-dependent water and carbon dioxide saturation surface in silicate melts; its capability to extend further that knowledge by revealing additional aspects not yet experimentally highlighted; and some examples of the use of the model to explore the characteristics of real magmatic systems and simulate their dynamics.