Investigating Silicate Melts and Glasses for Insights into Igneous Processes
Understanding the structure, properties and dynamics of silicate melts is fundamental for modeling magma transport and eruption processes, and here I present experimental approaches to study these aspects across compositions from ultramafic to felsic. Using a rapid-quench multi-anvil technique, we synthesized hydrous peridotitic glasses and constrained water speciation by infrared spectroscopy. Combining our data with literature, we established compositional trends of molar absorptivities for infrared absorption bands of water in rhyolitic to peridotitic glasses. We also observed nanocrystallization in Fe-bearing andesitic melts for the first time using in situ high-temperature Raman spectroscopy and studied their evolution with temperature and time. In addition, we developed a novel ex-situ falling-sphere technique to verify and build viscosity models of hydrous silicate melts. Finally, a new fragmentation apparatus enabled experiments under realistic volcanic conditions. Together, these approaches link melt structure, rheology and fragmentation, advancing our understanding of igneous processes from mantle melting to explosive eruptions.