Graduation Year
2025
Document Type
Dissertation
Degree
Ph.D.
Degree Name
Doctor of Philosophy (Ph.D.)
Degree Granting Department
Geosciences
Major Professor
Aurelie Germa, Ph.D.
Committee Member
Zachary Atlas, Ph.D.
Committee Member
Sylvain Charbonnier, Ph.D.
Committee Member
Xavier Quidelleur, Ph.D.
Keywords
Eruptive dynamics, Geochemistry, Ignimbrite, Martinique, Mineral-melt equilibrium, Pre-eruptive storage conditions
Abstract
This dissertation investigates the volcanic systems of Martinique Island, focusing on magma storage conditions, magmatic evolution, and eruption dynamics. Chapter 3 presents a petrographic analysis of volcanic rocks from the island’s old, intermediate, and recent arcs, examining the evolution of plagioclase textures and the increasing abundance of other mineral phases, such as pyroxene, amphibole, olivine, and quartz, which provide insights into changing magmatic conditions. The main research is divided into two projects. Chapter 4 addresses the pre-eruptive storage conditions (pressure and temperature) of magmas beneath recent (<5 Ma) volcanic complexes (Morne Jacob, Piton du Carbet, Trois Îlets, Mt. Conil, and Mt. Pelée), exploring magma evolution, crystallization, and the role of lower crustal injections and flank collapses in triggering eruptions. Results reveal variable magma storage depths (<6 km), with significant temperature and pressure variations, indicating complex magmatic systems. Chapter 5 focuses on the Roches-Genty ignimbrite in southwestern Martinique, investigating its stratigraphy, geochemistry, and age using field mapping, grain size analysis, and 40Ar/39Ar dating. The study identifies two distinct sub-Plinian eruptive phases associated with the Dizac ignimbrite, with ages of 3.37 ± 0.14 Ma and 2.10 ± 0.26 Ma, providing insights into past explosive volcanic activity. Geochemical analysis confirms an andesitic composition, similar to regional volcanic systems. This dissertation enhances understanding of Martinique’s volcanic history, providing valuable insights into magmatic processes and eruption dynamics, with implications for volcanic hazard assessments in the Lesser Antilles.
Scholar Commons Citation
Martens, Abigail, "New Petrographic and Geochemical Constraints on Pre-eruptive Storage Conditions and Their Control on Eruptive Styles in Martinique’s Recent Volcanic Systems" (2025). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/10978
