February 13, 2019
Susanne Seitz to present geology seminar Feb. 14
Susanne Seitz, research associate in Earth and environmental sciences at Vanderbilt University, will present a geology seminar at 4 p.m. Thursday, Feb. 14, in 213 Thompson Hall. The title of her presentation is "High-silica rhyolites of the Chon Aike Province (Patagonia, Argentina) — The "crystal's-eye" view on crustal melting and magmatic timescales."
Seitz will present secondary ion mass spectroscopy, or SIMS, oxygen isotope measurements on quartz and zircon and discuss the role of crustal melting in the formation of the rhyolites from the El Quemado Complex. She will then continue with a more detailed look on the late history of those rhyolites, emphasizing textural differences between crystal-rich and crystal-poor rhyolites. Finally, she presents timescales of quartz crystallization based on NanoSIMS Ti profiles and discuss their implication on magma accumulation before eruption.
The Jurassic high-silica rhyolites of the El Quemado Complex in southern Argentina are part of the silicic large igneous Chon Aike Province. In the study area, the El Quemado Complex is dominated by crystal-rich rhyolitic ignimbrites and crystal-poor rhyolitic lava flows. The information stored in quartz and zircon crystals from those rhyolites is used to answer the questions:
- What is the magma source for those high-silica rhyolites?
- What is the nature of crustal magma storage?
- What timescales can we expect for magma accumulation before eruption?