Volcanology Commons^™

Seismological Investigations Of Magmatic Systems Using Dense Nodal Arrays, Wenkai Song

Earth and Planetary Sciences ETDs

Understanding the internal architecture of magmatic systems is crucial for volcanology, yet conventional geophysical techniques often lack the resolution to image their fine-scale structures. This dissertation leverages unique datasets from dense nodal arrays to investigate the upper crustal magmatic systems beneath Yellowstone Caldera, Valles Caldera, and Mount St. Helens. At Yellowstone, I processed vibroseis data to delineate the top of the modern magma reservoir and evaluate the thermal connection between the magmatic and the overlying hydrothermal systems. At Valles, 3D radial seismic anisotropy imaging reveals strong positive radial anisotropy within the reservoir, indicating an organized structure of horizontally sill-like melt …

Seeking Structure In Complex Systems: From Feature Analysis To Space-Time Causal Discovery With Earth Science Applications, Jeffrey J. Nichol

Computer Science ETDs

Complex systems are difficult to study because of their many interacting parts, emergent phenomena, and feedback loops. These systems underpin all life on Earth. We need improved tools for seeking an understanding of them. This body of research presents my investigations into data-driven methods for understanding complex systems, including my invention of a novel causal discovery meta-algorithm for space-time gridded data. I demonstrated machine learning feature importance and causal discovery capabilities for comparing simulated and observed climate data. I developed a new benchmark for modeling space-time dynamics of locally driven phenomena and examined a prominent causal discovery algorithm. Finding that …

First Insight On The Genesis Of Iron Oxide-Hydroxide Biospeleothems In Rancho Chico Lava Tube, Mexico, Rafael López-Martínez, Elizabeth Solleiro-Rebolledo, Rocio Alcántara-Hernández, Teresa Pi Puig, Sergey Sedov, Daisy Valera Fernández, M. Nayeli Luis-Vargas, Yasmany Lima Vera, Jesús Solé, Ramon Espinasa-Pereña

International Journal of Speleology

Iron is a common element in lava tube systems, typically observed as thin crusts or inferred from the reddish coloration of secondary mineral deposits. In this study, we describe iron oxide-hydroxide biospeleothems discovered in the Rancho Chico Lava Tube, located within the Xalapa Monogenetic Volcanic Field in Mexico. We adopt an integrative approach combining petrography, soil micromorphology, scanning electron microscopy, mineralogy, and 16S rRNA gene metabarcoding. DNA sequencing reveals the presence of microorganisms such as Acidithiobacillus, Gallionella, and members of the Leptospirillaceae family, which may be involved in the oxidation of Fe²⁺ within the lava tube. The source …

Large-Scale Groundwater System Characterization Using Pressure Responses To Barometric Perturbations Caused By The 2022 Hunga Tonga-Hunga Ha'apai Volcanic Eruption, Anhua He, Yang Liu, Fan Zhang, Huamei Zhang, Ramesh P. Singh, Yanzhang Wang

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hunga Tonga-Hunga Ha'apai volcanic erupted on 15 January 2022, causing Lamb waves to propagate throughout the global troposphere. However, reports on volcanic eruptions–pressure fluctuations and water level dynamics are lacking. We quantified the propagation processes of Lamb waves induced by the Tonga volcanic eruption. Barometric pressure data collected at 1-min intervals at 485 meteorological stations in China showed that the eruption induced an atmospheric pressure event with an amplitude of ∼2 hPa over an hour and a wave speed of 295 m/s. Concomitant groundwater levels were available at 338 wells to find the barometric response to the volcanic event. The …

Aerial Robotic Studies Of Volcanic Co2 Emissions, John Ericksen

Computer Science ETDs

Volcanic systems are inherently complex, involving dynamic interactions among magma flow, gas emissions, and atmospheric dispersion. This dissertation focuses on developing and analyzing autonomous UAS algorithms for efficiently surveying volcanic CO2 plumes, introducing several novel methods: the LoCUS algorithm, a swarm coordination and self-healing algorithm that supports gradient-based plume tracking, a transect-based technique that employs a 2D Gaussian fit to calculate CO2 plume flux, and the Sketch algorithm for rapid plume boundary tracing. By treating multiple UAS as a single scientific instrument, these methods leverage swarm algorithms to use in-situ data in ways impossible with individual drones. Validated through simulations …

Magma Evolution And Eruptive History Of Three Fingered Jack: A Mafic Composite Volcano In The Central High Cascades Of Oregon, Javaria Aziz

Dissertations and Theses

The central High Cascades graben in Oregon has been a center for mafic volcanism since its initiation. Three Fingered Jack is one of the larger mafic composite cones in the graben, located 20km south of Mount Jefferson. Three Fingered Jack erupted between 142.1 - 150.8ka, based on Ar⁴⁰/Ar³⁹ age dates. This study provides stratigraphic, compositional and petrographic evidence to understand the eruptive history of Three Fingered Jack and the processes involved in generating compositionally diverse basaltic andesites here.

The basaltic andesites of Three Fingered Jack show three compositional trends of magma evolution: 1) enrichment, 2) depletion and …

Geochemistry Of The Inyo Volcanic Chain, And Evaluation Of The Portable Niton Xrf Instrument, Dylan Terry

Electronic Theses, Projects, and Dissertations

The Inyo Volcanic Chain (IVC) is a series of rhyolitic lava domes straddling the northwest rim of the Long Valley Caldera (LVC), most recently erupting ~650 years ago, producing the South Deadman, Obsidian, and Glass Creek Domes. For this study, samples were analyzed for geochemistry and petrography at six of the IVC domes. To measure geochemistry, a portable x-ray fluorescence machine (PXRF) was used, in part to test how well it performed on felsic rocks. The PXRF performed poorly with the factory calibration in detecting most elements, though detection of some elements improved with a calibration curve applied. The three …

Provenance Of Clastic Sedimentation In Middle Deadfall Lake And Paleoclimate Modelling Of Glacier Fluctuations At Mount Eddy, Eastern Klamath Mountains, California, Usa, Emily Stebbins

Cal Poly Humboldt theses and projects

This study reconstructs the timing, extent, and paleoclimate conditions associated with late Pleistocene glaciation in the Mount Eddy region of the eastern Klamath Mountains, northern California and investigates the provenance of clastic sedimentation in Middle Deadfall Lake, just east of Mt Eddy. Using a multi-pronged approach that combines geomorphic mapping, sediment core analysis, X-ray fluorescence (XRF) geochemistry, tephrochronology, and glacier modeling using PalaeoIce 2.0, this research provides new insights into glacial dynamics and climate variability in a region with limited glacially derived paleoclimate datasets, as well as past volcanic eruption deposits.

Field and GIS-based geomorphic mapping identified three generations …

Proximal Seismic Tracking Of Pyroclastic Density Currents At Volcán De Fuego, Guatemala, Jacob A. Krier

Dissertations, Master's Theses and Master's Reports

Pyroclastic Density Currents (PDCs) are deadly flows of ash, tephra, gas, and solidified magma which predominantly occur when an ash plume collapses during a volcanic eruption. PDCs are also able to form when large deposits of ash at the summit of a volcano are displaced during an eruption and flow downslope. This is typically the mechanism behind PDCs that occur at Volcán de Fuego such as one that occurred in 2018 killing at least 430 people. The purpose of this paper is to track the propagation of PDCs that occurred at Fuego seismologically in order to better understand how they …

Quantifying So₂ Emissions From Explosive Events Of The 2021 La Soufrière Eruption Using Dscovr/Epic, Yuxi Jin

Dissertations, Master's Theses and Master's Reports

Volcanic eruptions release large quantities of gases, including sulfur dioxide (SO₂), aerosol precursors, and ash into the atmosphere. Quantifying the emission fluxes and temporal variability of SO₂ is crucial for understanding volcanic processes and assessing their impacts on air quality, climate, and aviation safety. Episodic vulcanian to sub-Plinian explosive eruptions are a common feature of many arc volcanoes, but the underlying causes of such episodic behavior remain poorly understood. The 2021 La Soufrière eruption (St. Vincent) featured up to 40 discrete eruptive events between April 9 and April 22, presenting a rare opportunity to analyze time-resolved volcanic SO₂ emissions during …

The Petrology And Geochemistry Of The Montagna Grande-Monte Gibele Trachytic Shield Volcano (Pantelleria, Italy)., John C. White, Ray Macdonald, Pierangelo Romano, Boguslaw Baginski, Silvio G. Rotolo, Beata Marciniak-Maliszewska, Alessandra Cinquegrani

EKU Faculty and Staff Scholarship

The 45.7 ± 1.0 ka (2σ) eruption of the compositionally zoned (comenditic trachyte to pantellerite) Green Tuff ignimbrite on the volcanic island of Pantelleria, Italy, was followed by the extrusion of a series of post-caldera metaluminous to mildly peralkaline trachyte lavas between 26.2 ± 2.0 and 22.3 ± 2.9 ka (2σ). This study uses whole-rock major- and trace-element compositions, mineral compositions, geothermobarometry, and petrogenetic models to examine the role of trachytes in the evolution of the Pantelleria magma system. Although previous studies have suggested that all of these units are consanguineous and form a liquid line of descent (LLOD) from …