A simple and robust method for calculating temperatures of granitoid magmas

Abstract Calculating the temperatures of magmas from which granitoid rocks solidify is a key task studying their petrogenesis, but few geothermometers are satisfactory. Zircon saturation thermometry has been most widely used because it conceptually simple and practically convenient, based on experimental calibrations with significant correlation calculated zircon temperature ( T Zr ) zirconium (Zr) content in granitic melt (i.e., ∝ MELT ). However, application this to natural can be misleading, resulting having no geological significance. This requires compound bulk compositional parameter M as input variables. As information not available, petrologists simply use bulk-rock (Zr BULK-ROCK calculate . In calibration, shows , thus only function Because represent cumulates or mixtures crystals before magma solidification amount sample reside varying origin (liquidus, captured inherited crystals) unknown modal abundance, cannot equated that unknown. Hence, using have significance both theory practice. an alternative, we propose empirical equation $$T_{SiO_{2}}$$ T S i O 2 (°C) = -14.16 × SiO 2 + 1723 for studies, rely exact values individual samples focus similarities differences between suites comparison. robust experimentally determined phase equilibria 1/SiO