Timing and Source of Alkali-Enrichment at Mt. Etna, Sicily: Constraints from Clinopyroxene Geobarometry and in situ Sr Isotope Data

Kaitlyn Nelson
November 2013

Introduction and Purpose

Understanding the magmatic processes that occur within the magma storage and transport system of a volcano is essential for the improvement of associated eruptive hazards prediction and mitigation. For example, documenting eruption frequency, magnitude of ground deformation prior to eruption, and volume of erupted material informs scientists about the temporal and spatial evolution of a magma chamber (Caricausi et al. 2003; Patane et al. 2005). Furthermore, the collection and analysis of compositional data allows volcanologists to document the thermo- chemical origin and evolution of magmas within a magma chamber, providing insight into subvolcanic processes that influence eruption style and volatility (Metrich et al. 2004; Schiano et al. 2001; Tonarini et al. 2001). As such, characterization of the magmatic processes that impact a volcanic system is crucial for the improved assessment of volcanic hazards, and ultimately helps to preserve both property and life.

I propose to use geobarometry and in situ Sr isotope data from clinopyroxene in 3 pre- and 3 post-1971 lavas to probe the timing and depth of the enrichment, as well as to characterize the mid- to lower-crustal magma chamber history of the volcano. These new data may help resolve a longstanding debate among volcanologists regarding the source of alkali-enrichment, as well as provide information about the processes that influence eruption style, aiding in eruptive hazard prediction and mitigation.

Full Thesis Proposal (PDF format)