Abstract
This work may have a narrow geographic focus, namely a handful of steep and densely forested valleys of the Southern Italian Alps, but its scientific goals are certainly wide. Through a combined analyses of the spatial distribution, geochemical characteristics and temporal duration of the Permian silicic magmatism in the renown Ivrea crustal section (Sesia Magmatic System), this dissertation addresses fundamental questions regarding the physical mechanisms of rhyolitic magma storage, mobilization and eruption.
A brief introduction serves to define the broader context of the scientific questions addressed in the three main chapters of this dissertation. Through Chapters 2 to 4 we apply a set of petrologic, and geochronologic techniques to the intrusive and volcanic products of a transcrustal magmatic system. These constrains provide the image of a long-lived (~ 1 Myr), crystalline rhyolitic magma body residing at upper crustal conditions (400 to 200 kbar), episodically replenished by magmas of variable compositions. This magmatic reservoir was a dynamic environment were the active separation of solid and liquid phase helped create a thick cap of potentially eruptible rhyolitic material. We utilize this uniquely exposed system to test the consistency of models of magma chamber assembly and evolution developed solely in volcanic environment or through numerical modeling. Ultimately, we indicate that the plutonic record can document physical processes and timescales usually associated with volcanic processes, opening a new chapter in the volcanic-plutonic connection book.
Degree Date
Fall 2021
Document Type
Dissertation
Degree Name
Ph.D.
Department
Earth Sciences
Advisor
Rita C. Economos
Second Advisor
Robert T. Gregory
Third Advisor
James E. Quick
Fourth Advisor
Crayton J. Yapp
Fifth Advisor
Olivier Bachmann
Subject Area
Physical Sciences
Number of Pages
222
Format
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Recommended Citation
Tavazzani, Lorenzo, "Timescales and Dynamics of Rhyolitic Melt Generation in Upper Crustal Magmatic Reservoirs: Insights from new Geochronologic and Petrologic Data on the Valle Mosso Pluton and Sesia Caldera, Sesia Magmatic System, Italy" (2021). Earth Sciences Theses and Dissertations. 23.
https://scholar.smu.edu/hum_sci_earthsciences_etds/23
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