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Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa 2019 Michigan Technological University

Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa

Dissertations, Master's Theses and Master's Reports

The Puhimau geothermal area, located near the summit of the Kilauea volcano, Hawaii, has been suggested to represent a ‘window’ into the East Rift Zone. The quantification of CO2 and H2S soil gas emissions improves our understanding of its gas emission mode- including total emission and spatial distribution and contribute to a more accurate estimation of total CO2 and H2S in the thermal area – and how these gas emissions relate to observed vegetation health from satellite data. The total emission of CO2 and H2S was interpolated by the sequential Gaussian …


Testing The Use Of Vegetation Indices As Indicators Of Pre-Eruptive Volcanic Unrest At Kilauea Volcano, Hawaii, Quelyn Bekkering 2019 Michigan Technological University

Testing The Use Of Vegetation Indices As Indicators Of Pre-Eruptive Volcanic Unrest At Kilauea Volcano, Hawaii, Quelyn Bekkering

Dissertations, Master's Theses and Master's Reports

Satellite remote sensing has become an integral part of pre-eruptive and long-term volcano monitoring due to its low cost, spatial and temporal coverage, and time-series analysis capabilities. Pre-eruptive unrest at volcanoes can include increased fluxes of heat and volcanic gases, which can be manifested either directly (e.g., the appearance of thermal anomalies or fumaroles) or indirectly (e.g., through impacts on vegetation health and extent). We are evaluating the use of novel, high spatial and temporal resolution data from the Planet Labs cubesat constellation to monitor changes in vegetation related to volcanic unrest. We present results from a study of key …


Volatiles And Trace Element Contents In Melt Inclusions From The Zoned Green Tuff Ignimbrite (Pantelleria, Sicily): Petrological Inferences., Pierangelo Romano, John C. White, Alessandro Ciulla, Ida Di Carlo, Claudia D'Oriano, Patrizia Landi, Silvio G. Rotolo 2019 University of Palermo

Volatiles And Trace Element Contents In Melt Inclusions From The Zoned Green Tuff Ignimbrite (Pantelleria, Sicily): Petrological Inferences., Pierangelo Romano, John C. White, Alessandro Ciulla, Ida Di Carlo, Claudia D'Oriano, Patrizia Landi, Silvio G. Rotolo

EKU Faculty and Staff Scholarship

The island of Pantelleria is one of the best known localities of bimodal mafic-felsic magmatism (alkali basalt and trachyte-pantellerite). Among the felsic rocks, the coexistence in a single eruption of products of both trachyte and pantellerite compositions is limited to few occurrences, the Green Tuff (GT) ignimbrite being one of these. The GT is compositionally zoned from pantellerite (70.1 wt% SiO2, mol Na+K/Al = 1.86, 1871 ppm Zr) at the base to crystal-rich (>30 vol%) comenditic trachyte (63.4 wt% SiO2, mol Na+K/Al = 1.10, 265 ppm Zr) at the top, although the pantellertic compositions dominate the erupted volume. We …


The Leyva Canyon Volcano, Big Bend Ranch State Park, Presidio Co., Texas., John C. White, Kevin M. Urbanczyk, Kelly Watson 2019 Eastern Kentucky University

The Leyva Canyon Volcano, Big Bend Ranch State Park, Presidio Co., Texas., John C. White, Kevin M. Urbanczyk, Kelly Watson

EKU Faculty and Staff Scholarship

Leyva Canyon volcano is an Oligocene (37.3 to 27.1 Ma) trachyte shield volcano whose eruptive and volcaniclastic deposits of rhyolite and trachyte lavas, ash-flow tuffs, lahars, and associated sedimentary rocks comprise the Leyva Canyon Member of the Rawls Formation. The lavas and tuffs originated from vents located near the present-day "Bofecillos vent" in the central Bofecillos Mountains, approximately 5 km west of the Sauceda Ranger Station in Big Bend Ranch State Park in southernmost Presidio County, Texas. The pyroclastic and volcaniclastic units form the distinctive cliffs and caves at the periphery of the Bofecillos Mountains, with the caves developing in …


Carbonatites As A Record Of The Carbon Isotope Composition Of Large Igneous Province Outgassing, Ellen Gales 2019 CUNY City College

Carbonatites As A Record Of The Carbon Isotope Composition Of Large Igneous Province Outgassing, Ellen Gales

Dissertations and Theses

Large igneous province (LIP) eruptions have been linked in some cases to major perturbations of Earth’s carbon cycle. However, few observations directly constrain the isotopic composition of carbon released by LIP magmas because carbon isotopes fractionate during degassing, which hampers understanding of the relative roles of mantle versus crustal carbon reservoirs. Carbonatite magmatism associated with LIPs provides a unique window into the isotopic systematics of LIP carbon because the majority of carbon in carbonatites crystalizes rather than degassing. Here, we present new δ13C data for the Guli carbonatites in the Siberian Traps. In addition, we compile ~260 published …


Regional Sulfur Isotope Study Of The Vms Deposits In The Penokean Volcanic Belt, Nicholas M. Moleski 2018 Western Michigan University

Regional Sulfur Isotope Study Of The Vms Deposits In The Penokean Volcanic Belt, Nicholas M. Moleski

Masters Theses

The Penokean Volcanic Belt (PVB), located in northern Wisconsin and Upper Peninsula, Michigan hosts several volcanogenic massive sulfide deposits (VMS) including the well-known deposits of Flambeau and Crandon. The host rocks of the VMS deposits are Paleoproterozoic in age overlying Archean age basement rocks. This study provides δ34S (VCDT) values for the following deposits within the PVB; (1) Eisenbrey, (2) Schoolhouse, (3) Bend, (4) Flambeau, (5) Reef, (6) Horseshoe, and (7) Back Forty, and explains the distribution of δ34S values in the region.

The study reveals tight ranges of δ34S values for each deposit …


Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński 2018 University of Warsaw

Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński

EKU Faculty and Staff Scholarship

The Green Tuff Ignimbrite, Pantelleria, is compositionally zoned from pantellerite at the base to comenditic trachyte at the top, the variation apparently representing an inverted vertical zonation in the pre-eruptive reservoir. The main phenocryst assemblages are alkali feldspar + olivine + clinopyroxene + ilmenite + apatite in the trachytes and alkali feldspar + aenigmatite + clinopyroxene + quartz in the rhyolites. Thermodynamic modelling indicates that the temperature range was ~900–700°C, fO2 FMQ –1.5 to FMQ –0.5 (where FMQ is fayalite–magnetite–quartz buffer) and aSiO2 (relative to quartz saturation) 0.74–1.00. Melt water contents ranged from ~1wt % in the trachytes to ~4wt …


Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa, Kevin W. Blackwood, Lainee A. Sanders, Stacy I. Gantt-Blackwood 2018 East Central University

Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa, Kevin W. Blackwood, Lainee A. Sanders, Stacy I. Gantt-Blackwood

International Journal of Speleology

The Upper Geyser Basin in Yellowstone National Park occurs over a siliceous hydrothermal terrane containing numerous hot springs and geysers. The pool and vent-conduit geometries of these hydrothermal features share a resemblance to conventional karst features known from other rock types, suggesting karst processes could be responsible for their origin and/or evolution. Hypogene speleogenesis is a cave-forming process in which the formation of caves is decoupled from and occurs independently of surface recharge. The geologic setting for hypogene speleogenesis typically occurs at the distal end of regional groundwater systems wherein the hydrogeology is manifested by ascending fluids and/or by geochemical …


Volcanic Glass As A Paleoenvironmental Proxy: Comparing Preparation Methods On Ashes From The Lee Of The Cascade Range In Oregon, Usa, Tessa Boe Carlson 2018 Portland State University

Volcanic Glass As A Paleoenvironmental Proxy: Comparing Preparation Methods On Ashes From The Lee Of The Cascade Range In Oregon, Usa, Tessa Boe Carlson

Dissertations and Theses

Deuterium ratios (δD) of hydrated volcanic glass have been used to reconstruct paleoenvironments, although the reliability and proper sample preparation protocol have been debated. In this study, hydrated volcanic ash samples from the lee of the Cascades were prepared using two separate methods. Method 1 involves sonicating and rinsing samples with hydrochloric acid (HCl) followed by hand-selection of glass shards (125-212µm). Method 2 requires hydrochloric acid (HCl) and hydrofluoric acid (HF) abrasion as well as heavy liquid separation of shards (70-150µm). Method 2 produced more consistent results with decreased intra-replicate variability in both water content (-0.92 wt. %) and deuterium …


Extremely High Diversity Of Sulfate Minerals In Caves Of The Irazú Volcano (Costa Rica) Related To Crater Lake And Fumarolic Activity, Andrés Ulloa, Fernando Gázquez, Aurelio Sanz-Arranz, Jesús Medina, Fernando Rull, José María Calaforra, Guillermo E. Alvarado, María Martínez, Geoffroy Avard, J. Maarten De Moor, Jo De Waele 2018 Universidad de Costa Rica

Extremely High Diversity Of Sulfate Minerals In Caves Of The Irazú Volcano (Costa Rica) Related To Crater Lake And Fumarolic Activity, Andrés Ulloa, Fernando Gázquez, Aurelio Sanz-Arranz, Jesús Medina, Fernando Rull, José María Calaforra, Guillermo E. Alvarado, María Martínez, Geoffroy Avard, J. Maarten De Moor, Jo De Waele

International Journal of Speleology

The caves of the Irazú volcano (Costa Rica), became accessible after the partial collapse of the NW sector of the Irazú volcano in 1994, offering the opportunity to investigate active minerogenetic processes in volcanic cave environments. We performed a detailed mineralogical and geochemical study of speleothems in the caves Cueva los Minerales and Cueva Los Mucolitos, both located in the northwest foothills of the main crater. Mineralogical analyses included X-ray diffraction (XRD) and Raman spectroscopy, while geochemical characterization used Energy Dispersive X-ray spectroscopy (EDX) coupled to Scanning Electron Microscopy (SEM). In addition, measurements of environmental parameters in the caves, …


Infrasound Tornillos Produced By Volcán Cotopaxi’S Deep Crater, J. B. Johnson, M. C. Ruiz, H. D. Ortiz, L. M. Watson, G. Viracucha, P. Ramon, M. Almeida 2018 Boise State University

Infrasound Tornillos Produced By Volcán Cotopaxi’S Deep Crater, J. B. Johnson, M. C. Ruiz, H. D. Ortiz, L. M. Watson, G. Viracucha, P. Ramon, M. Almeida

CGISS Publications and Presentations

We characterize and interpret a new type of infrasound signal originating from the summit of Volcán Cotopaxi (Ecuador) that was primarily observed between September 2015 and March 2016, following the 2015 eruptive period. This infrasound waveform is a slowly decaying sinusoid with exceptional low-frequency (fp = 0.2 Hz) and high quality factor (Q = ~10) and resembles the shape of tornillo seismic waveforms. The repeating events, occurring about once per day in early 2016, are stable in frequency content, and we attribute them to excitation of a vertical-walled crater, with radius of about 125mand length of 300 …


Lava, Ash Flows, Mudslides And Nasty Gases: Good Reasons To Respect Volcanoes, Brittany Brand 2018 Boise State University

Lava, Ash Flows, Mudslides And Nasty Gases: Good Reasons To Respect Volcanoes, Brittany Brand

Geosciences Faculty Publications and Presentations

Volcanoes are beautiful and awe-inspiring, but the ongoing eruption of Kilauea on Hawaii’s Big Island is showing how dangerous these events can be. So far this event has destroyed dozens of homes and displaced hundreds of people, but no deaths or serious injuries have been reported. Other volcanic eruptions have had deadlier impacts.


Estimation Of Porosity And Water Saturation In Dual-Porosity Pyroclastic Deposits From Joint Analysis Of Compression, Shear, And Electromagnetic Velocities, Andrew C. Gase, John H. Bradford, Brittany D. Brand 2018 University of Texas at Austin

Estimation Of Porosity And Water Saturation In Dual-Porosity Pyroclastic Deposits From Joint Analysis Of Compression, Shear, And Electromagnetic Velocities, Andrew C. Gase, John H. Bradford, Brittany D. Brand

Geosciences Faculty Publications and Presentations

In situ measurements of porosity and water saturation of pyroclastic deposits have the potential to improve interpretations of geology and hydrology in volcanic regions, and to provide more accurate estimates of dense rock equivalent for volcanic eruptions. However, rock-property models must consider the dual-porosity structure of pyroclastic deposits (i.e., vesicles within pumices and intergranular pores). Vesicularity, intergranular porosity, and water saturation all affect the density, elasticity, and dielectric properties of pyroclastic materials, which control seismic and electromagnetic velocities. The data from active seismic and ground-penetrating radar (GPR) techniques may improve porosity and water saturation estimation if the responses of seismic …


Diverse Eruptive Activity Revealed By Acoustic And Electromagnetic Observations Of The 14 July 2013 Intense Vulcanian Eruption Of Tungurahua Volcano, Ecuador, J. F. Anderson, J. B. Johnson, A. L. Steele, M. C. Ruiz, B. D. Brand 2018 Boise State University

Diverse Eruptive Activity Revealed By Acoustic And Electromagnetic Observations Of The 14 July 2013 Intense Vulcanian Eruption Of Tungurahua Volcano, Ecuador, J. F. Anderson, J. B. Johnson, A. L. Steele, M. C. Ruiz, B. D. Brand

CGISS Publications and Presentations

During the powerful July 2013 eruption of Tungurahua volcano, Ecuador, we recorded exceptionally high amplitude, long‐period infrasound (1,600‐Pa peak‐to‐peak amplitude, 5.5‐s period) on sensors within 2km of the vent alongside electromagnetic signals from volcanic lightning serendipitously captured as interference. This explosion was one of Tungurahua's most powerful vulcanian eruptions since recent activity began in 1999, and its acoustic wave is among the most powerful volcanic infrasound ever recorded anywhere. We use these data to quantify erupted volume from the main explosion and to classify postexplosive degassing into distinct emission styles. Additionally, we demonstrate a highly effective method of recording lightning‐related …


Areal Extent And Volumes Of The Dinner Creek Tuff Units, Eastern Oregon Based On Lithology, Bulk Rock Composition And Feldspar Mineralogy, Teresa Rae Hanna 2018 Portland State University

Areal Extent And Volumes Of The Dinner Creek Tuff Units, Eastern Oregon Based On Lithology, Bulk Rock Composition And Feldspar Mineralogy, Teresa Rae Hanna

Dissertations and Theses

The Dinner Creek Tuff erupted during a period of rhyolitic volcanism coeval to the flood volcanism associated with the Columbia River Basalt Group. The High Rock Caldera Complex, Lake Owyhee and McDermitt volcanic fields account for ~90% of the rhyolites erupted between 16.7-15.0 Ma. Situated at the northern end of the Lake Owyhee volcanic field, the Dinner Creek Tuff was originally mapped as a ~2,000 km2 single ignimbrite confined to the Malheur Gorge. Streck et al. (2015) correlated tuff outcrops previously mapped as generic Miocene welded tuff as well as local units such as the "Mascall" or "Pleasant Valley" …


Conflicting Theories: Impact And Volcanism, Dimitrik Johnson 2018 Germanna Community College

Conflicting Theories: Impact And Volcanism, Dimitrik Johnson

Student Writing

The K-Pg extinction (or K-T extinction), more commonly referred to as the extinction of the dinosaurs, is the most recent mass extinction event in Earth’s history. The causes of the event have been widely debated, with the two main theories being a large asteroid impact or volcanism. While some scientists disagree, the most popular and agreed upon theory is that a large asteroid impacted Earth 65 million years ago, creating a toxic dust cloud that filled the atmosphere, and resulted in the eventual extinction of most of the dinosaurs. This theory was first brought to life by Luis Alvarez, his …


Identifying The Origins Of Volcanic Ash Deposits Using Their Chemical And Physical Compositions, Emmanuel Soto 2018 Florida International University

Identifying The Origins Of Volcanic Ash Deposits Using Their Chemical And Physical Compositions, Emmanuel Soto

FIU Electronic Theses and Dissertations

Recent ocean sediments collected offshore Chile by Ocean Drilling Program Leg 202 contained layers of volcanic ash of unknown origin. These deposits may have originated from sources in the Southern Volcanic Zone (SVZ) within the Andean Volcanic Belt to the east, or from explosive volcanoes in the southwestern Pacific transported by westerly prevailing winds. In this study, mineral and glass textures and compositions of Leg 202 ashes were evaluated to try to determine the sources of the ash layers. Ash fragments were imaged and analyzed for major elements using an SEM with X-Ray detector and for trace elements using LA-ICPMS. …


Forecasting The Eruption Of An Open‐Vent Volcano Using Resonant Infrasound Tones, Jeffrey B. Johnson, Leighton M. Watson, Jose L. Palma, Eric M. Dunham, Jacob F. Anderson 2018 Boise State University

Forecasting The Eruption Of An Open‐Vent Volcano Using Resonant Infrasound Tones, Jeffrey B. Johnson, Leighton M. Watson, Jose L. Palma, Eric M. Dunham, Jacob F. Anderson

CGISS Publications and Presentations

Open‐vent volcanic systems with active degassing are particularly effective at producing infrasound that exhibits resonant tones controlled by the geometry of the volcano's crater. Changes in the infrasound character can thus provide constraints on a crater's lava level, which may vary dynamically in the lead‐up to an eruption. Here we show that the increasing frequency content and damping characteristics of the resonant infrasound at Volcán Villarrica (Chile) relate to lava lake position in its crater/conduit preceding its 2015 eruption. We model the acoustic response of Villarrica's crater to determine that the lake began to rise on 27 February and reached …


The Recent Volcanic History Of Axial Seamount: Geophysical Insights Into Past Eruption Dynamics With An Eye Toward Enhanced Observations Of Future Eruptions, William Wilcock, Robert Dziak, Maya Tolstoy, William Chadwick, Scott Nooner, DelWayne Bohnenstiel, Jacqueline Caplan-Auerbach, Felix Waldhauser, Adrien Amulf, Christian Ballard, Tai-Kwan Lau, Joseph Haxel, Yen Joe Tan, Charles Garcia, Samuel Levy, M. Everett Mann 2018 University of Washington

The Recent Volcanic History Of Axial Seamount: Geophysical Insights Into Past Eruption Dynamics With An Eye Toward Enhanced Observations Of Future Eruptions, William Wilcock, Robert Dziak, Maya Tolstoy, William Chadwick, Scott Nooner, Delwayne Bohnenstiel, Jacqueline Caplan-Auerbach, Felix Waldhauser, Adrien Amulf, Christian Ballard, Tai-Kwan Lau, Joseph Haxel, Yen Joe Tan, Charles Garcia, Samuel Levy, M. Everett Mann

Geology Faculty Publications

To understand the processes that form oceanic crust as well as the role of submarine volcanoes in exchanging heat and chemicals with the ocean and in supporting chemosynthetic biological communities, it is essential to study underwater eruptions. The world’s most advanced underwater volcano observatory—the Ocean Observatories Initiative Cabled Array at Axial Seamount—builds upon ~30 years of sustained geophysical monitoring at this site with autonomous and remote systems. In April 2015, only months after the Cabled Array’s installation, it recorded an eruption at Axial Seamount, adding to the records of two prior eruptions in 1998 and 2011. Between eruptions, magma recharge …


Tuhualite In A Peralkaline Rhyolitic Ignimbrite From Pantelleria, Italy, Boguslaw Baginski, Ray Macdonald, John C. White, Lidia Jezak 2018 University of Warsaw

Tuhualite In A Peralkaline Rhyolitic Ignimbrite From Pantelleria, Italy, Boguslaw Baginski, Ray Macdonald, John C. White, Lidia Jezak

EKU Faculty and Staff Scholarship

An occurrence of the rare mineral tuhualite (NaFe3+Fe2+Si6O15) is reported in a peralkaline rhyolitic ignimbrite from the 11 island of Pantelleria, Italy. The mineral formed during devitrification of glassy fiamme and varies in form from anhedral plates to 12 perfect euhedral in open vesicles. There is significant replacement of Fe2+ by Mn (FMQ in the presence of a 14 hydrous fluid.


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