Dr. Laura Waters
New Mexico Institute of Mining and Technology

Topic: Why doesn't continental crust evolve to its fullest potential?

Abstract: 

The paucity of high-silica rhyolite in volcanic arcs and its restricted occurrence as scattered aplite dikes throughout arc granitoid batholiths suggests there is a mechanism that prevents high-silica (near-eutectic) rhyolite melts from coalescing and erupting as discrete liquids at subduction zones. In contrast, large volumes (≥100 km^3) of high-silica rhyolite, including those that are relatively cold (700–750 °C) and hydrous, erupt in extensional tectonic settings. The emerging question is: What controls the eruption of high-silica rhyolite? In this talk, I use results of several experimental and petrologic studies on silica-rich magmas (rhyolites) from the Sierra Nevada Batholith and Long Valley to provide a crystallization (kinetic) perspective on what it takes to efficiently extract, move and erupt a eutectic melt and, thus, stratify continents.

Academic contact: Aaron Bell

Dr. Laura Waters
New Mexico Institute of Mining and Technology

Topic: Why doesn't continental crust evolve to its fullest potential?

Abstract: 

The paucity of high-silica rhyolite in volcanic arcs and its restricted occurrence as scattered aplite dikes throughout arc granitoid batholiths suggests there is a mechanism that prevents high-silica (near-eutectic) rhyolite melts from coalescing and erupting as discrete liquids at subduction zones. In contrast, large volumes (≥100 km^3) of high-silica rhyolite, including those that are relatively cold (700–750 °C) and hydrous, erupt in extensional tectonic settings. The emerging question is: What controls the eruption of high-silica rhyolite? In this talk, I use results of several experimental and petrologic studies on silica-rich magmas (rhyolites) from the Sierra Nevada Batholith and Long Valley to provide a crystallization (kinetic) perspective on what it takes to efficiently extract, move and erupt a eutectic melt and, thus, stratify continents.

Academic contact: Aaron Bell