Program > Browse abstracts by speaker > Beyer Christopher

Base-metal sulfur liquids (mattes) are key metasomatic and transport agents of highly siderophile elements (HSE) in the Earth's mantle. While previous studies have largely focused on sulfur-poor metallic liquids relevant to core formation, our high-pressure experiments using a multianvil apparatus explore the role of pressure, non-ferrous components in mattes, and silicate host mineralogy in governing matte wetting properties. We investigated conditions spanning both the lithospheric (6–7 GPa) and sub-lithospheric mantle (13 GPa), analyzing matte distribution via dihedral angle measurements in backscattered-electron images and 3D network topology in tomography scans. Our results reveal contrasting behaviors: while mattes in olivine-rich hosts exhibit high dihedral angles (94°–100°), a majorite-bearing assemblage at 13 GPa forms a percolative network with a mean dihedral angle of 43°, suggesting enhanced connectivity. Additionally, a garnet-bearing system showed reduced dihedral angles (72°), implying increased matte mobility. These findings indicate that pressure increase, particularly in mafic environments, promotes matte migration in the deep mantle, facilitating HSE transport in subducted oceanic crust while restricting matte mobility in depleted harzburgitic and ambient mantle lithologies at low melt fractions.