Zr solubility in mantle minerals at zircon saturation: Implications for zircon genesis in ultramafic rocks

Metasomatic zircons in ultramafic rocks are crucial in tracking orogenic processes. Metasomatic zircons are conceived to form by local zircon saturation resulting from effective Zr transport during metamorphic events and incomplete Zr accommodation in mantle minerals. However, the accommodation capacity of Zr in mantle minerals remains unknown, hampering our understanding of zircon genesis in ultramafic rocks. Here we performed experiments at 2.0−6.0 GPa and 1050−1200 °C and determined Zr content (solubility) in the mantle minerals at zircon saturation (ZCZS). The results show that ZCZS values for the main mantle minerals are olivine (ol, 3.68 ± 0.27 ppm)