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Full-Text Articles in Physical Sciences and Mathematics

Clouds In The Ancient Lunar Atmosphere: Water Ice Nucleation On Aerosol Simulants, Mariana C. Aguilar Jan 2024

Clouds In The Ancient Lunar Atmosphere: Water Ice Nucleation On Aerosol Simulants, Mariana C. Aguilar

The Journal of Purdue Undergraduate Research

Today’s moon is vastly different from what it was 3 billion years ago. At that time, it was home to a collisional atmosphere formed through massive amounts of volcanism, releasing enough subsurface gas to sustain surface pressures of up to 1 kPa. Observations of our solar system have taught us that all dense atmospheres are host to clouds and aerosols, and we expect the Moon’s to be no different. Knowing when, where, and under what conditions cloud particles form is important for understanding the evolution of the lunar atmosphere, how it reacted to temperature gradients, and how it cycled volatiles. …


Rift-Induced Disruption Of Cratonic Keels Drives Kimberlite Volcanism, Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. O'Reilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith, Anne Glerum Jul 2023

Rift-Induced Disruption Of Cratonic Keels Drives Kimberlite Volcanism, Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. O'Reilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith, Anne Glerum

Geology Faculty Publications and Presentations

Kimberlites are volatile-rich, occasionally diamond-bearing magmas that have erupted explosively at Earth’s surface in the geologic past1,2,3. These enigmatic magmas, originating from depths exceeding 150 km in Earth’s mantle1, occur in stable cratons and in pulses broadly synchronous with supercontinent cyclicity4. Whether their mobilization is driven by mantle plumes5 or by mechanical weakening of cratonic lithosphere4,6 remains unclear. Here we show that most kimberlites spanning the past billion years erupted about 30 million years (Myr) after continental breakup, suggesting an association with rifting processes. Our dynamical …


Large-Scale Volcanism On The Terrestrial Planets, Keenan Ben Golder May 2023

Large-Scale Volcanism On The Terrestrial Planets, Keenan Ben Golder

Doctoral Dissertations

Evidence for mafic volcanism has been found on each planet in the inner Solar System. Lava flows on these planets range in size from 10s to 1000s of kilometers in extent. I investigated large-scale lava flows on Mercury, Earth, and Mars throughout the chapters in this dissertation. Each of these lava flows provides an avenue to study the emplacement and evolution of lava on various planets and under differing conditions, the factors that affect their overall extent, and potential source areas.

Chapter One investigates large-scale lava flows in the Cerberus region on Mars, specifically to understand their emplacement history, material …


Thermomechanical Evolution Of A Magmatic System During A Caldera Cycle: Okataina Volcanic Center, New Zealand, Jacob Bonessi Jan 2022

Thermomechanical Evolution Of A Magmatic System During A Caldera Cycle: Okataina Volcanic Center, New Zealand, Jacob Bonessi

Dissertations, Master's Theses and Master's Reports

Caldera forming eruptions represent some of the largest simultaneous releases of mass and energy on the planet and pose a looming risk on a global scale. The study of the underlying magmatic systems is integral in understanding what leads to these large eruptions. This approach pairs a suite of major and trace element profiles from plagioclase with a grain texture classification and statistical analysis using Polytopic Vector Analysis (PVA) as proxies to explore potential changes in the thermomechanical state of the magmatic system at Okataina Volcanic Complex (OVC), New Zealand through its most recent caldera cycle. Results indicate systematic changes …


Geological And Geochemical Characteristics Of Cünür Volcanogenic Massive Sulfide Mineralization (Kastamonu, Turkey), Kurtuluş Günay Aug 2021

Geological And Geochemical Characteristics Of Cünür Volcanogenic Massive Sulfide Mineralization (Kastamonu, Turkey), Kurtuluş Günay

Bulletin of the Mineral Research and Exploration

Çangaldağ Metamorphic Complex (CMC) in Central Pontides is an accretionary complex consisting of Jurassic units. Mafic, felsic metavolcanics, metamorphic equivalents of deep marine sediments and mafic meta-lava/sill intercalations are the most distinct units of the complex. Cünür Volcanogenic Massive Sulphide (VMS) mineralization is associated with metavolcanic units of CMC. Metavolcanic units in the mineralization area contain volcanic rocks with compositions ranging from sub-alkali basalt to andesite and dacite (50.3 - 74.6 % SiO2). For 0.1 % Cu cut-off grade, 3,372,000 tons (t) of mineral resource with 0.28 % Cu, 0.50 % Zn and 0.19 ppm Au has been estimated. Ore …


Geochemical Features And Petrogenesis Of Gökçeada Volcanism, Çanakkale, Nw Turkey, Pınar Şen, Ramazan Sari, Erdal Şen, Cahit Dönmez, Serkan Özkümüş, Şahset Küçükefe Apr 2020

Geochemical Features And Petrogenesis Of Gökçeada Volcanism, Çanakkale, Nw Turkey, Pınar Şen, Ramazan Sari, Erdal Şen, Cahit Dönmez, Serkan Özkümüş, Şahset Küçükefe

Bulletin of the Mineral Research and Exploration

Gökçeada Island, which is situated west of Biga Peninsula, has widespread magmatism with variable ages. Lower-Middle Eocene Dağiçitepe volcanics are the oldest volcanic unit in the island and consist of lavas, tuff-tuffites. They are influenced by alteration and almost all minerals, except quartz, are transformed into other minerals. Lower Oligocene Gökçeada andesitic lava/ domes exhibiting hypocrystalline porphyric texture, are the products of NE-SW trending domes/ cryptodomes. The phenocrysts assemblages consist of plagioclase, hornblende, clinopyroxene ± biotite and quartz. Middle Miocene Eşelek volcanics, which occur as lavas and pyroclastic rocks, exhibit hypocrystalline porphyric and intersertal textures. They are composed of plagioclase, …


Alluvial-Lacustrine Sedimentation And Volcaniclastic Deposition In An Intracontinental Tectonic Graben: Paleoenvironmental Evolution Of The Neogene Sinanpaşa Basin, West-Central Turkey, Eli̇f Akiska, Baki̇ Erdoğan Varol Jan 2020

Alluvial-Lacustrine Sedimentation And Volcaniclastic Deposition In An Intracontinental Tectonic Graben: Paleoenvironmental Evolution Of The Neogene Sinanpaşa Basin, West-Central Turkey, Eli̇f Akiska, Baki̇ Erdoğan Varol

Turkish Journal of Earth Sciences

This study reports on the Sinanpaşa Basin, a typical example of the Miocene tectonic intracontinental grabens formed in West Anatolia, Turkey. The study reconstructs the paleoenvironmental and paleogeographic history of the graben based on a detailed sedimentological analysis of basin-fill deposits exposed mainly near the graben's northern and southern margins. The sedimentary paleoenvironments in the graben range from basin-margin alluvial fan systems and basin-axis fluvial distributary system to an intrabasinal shallow lake environment surrounded by peat-forming mires, changing from carbonate to more clayey, episodically evaporitic, and shifting its shorelines considerably. The spatial distribution and stratigraphic stacking of these paleoenvironments indicate …


A Survey Of Sierra Nevada Magmatism Using Great Valley Detrital Zircon Trace-Element Geochemistry: View From The Forearc, Kathleen D. Surpless, D. Clemens-Knott, A. P. Barth, M. Gevedon Jul 2019

A Survey Of Sierra Nevada Magmatism Using Great Valley Detrital Zircon Trace-Element Geochemistry: View From The Forearc, Kathleen D. Surpless, D. Clemens-Knott, A. P. Barth, M. Gevedon

Kathleen D. Surpless

The well-characterized Sierra Nevada magmatic arc offers an unparalleled opportunity to improve our understanding of continental arc magmatism, but present bedrock exposure provides an incomplete record that is dominated by Cretaceous plutons, making it challenging to decipher details of older magmatism and the dynamic interplay between plutonism and volcanism. Moreover, the forearc detrital record includes abundant zircon formed during apparent magmatic lulls, suggesting that understanding the long-term history of arc magmatism requires integrating plutonic, volcanic, and detrital records. We present trace-element geochemistry of detrital zircon grains from the Great Valley forearc basin to survey Sierra Nevadan arc magmatism through Mesozoic …


A Survey Of Sierra Nevada Magmatism Using Great Valley Detrital Zircon Trace-Element Geochemistry: View From The Forearc, Kathleen D. Surpless, D. Clemens-Knott, A. P. Barth, M. Gevedon Jan 2019

A Survey Of Sierra Nevada Magmatism Using Great Valley Detrital Zircon Trace-Element Geochemistry: View From The Forearc, Kathleen D. Surpless, D. Clemens-Knott, A. P. Barth, M. Gevedon

Geosciences Faculty Research

The well-characterized Sierra Nevada magmatic arc offers an unparalleled opportunity to improve our understanding of continental arc magmatism, but present bedrock exposure provides an incomplete record that is dominated by Cretaceous plutons, making it challenging to decipher details of older magmatism and the dynamic interplay between plutonism and volcanism. Moreover, the forearc detrital record includes abundant zircon formed during apparent magmatic lulls, suggesting that understanding the long-term history of arc magmatism requires integrating plutonic, volcanic, and detrital records. We present trace-element geochemistry of detrital zircon grains from the Great Valley forearc basin to survey Sierra Nevadan arc magmatism through Mesozoic …


Trace Element And Isotopic Fingerprinting Of Olivine Phenocrysts As Recorders Of Magmatic Processes In The Golden Trout Volcanic Field, Kern Plateau, Ca, Mark E. Szymanski Jan 2018

Trace Element And Isotopic Fingerprinting Of Olivine Phenocrysts As Recorders Of Magmatic Processes In The Golden Trout Volcanic Field, Kern Plateau, Ca, Mark E. Szymanski

Cal Poly Humboldt theses and projects

Quaternary mafic volcanism in the western Basin and Range and in the southeastern Sierra Nevada is largely controlled by extensional stresses that promote magma generation through decompression melting of the lithospheric and asthenospheric mantle. Where volcanism occurs in the Sierra Nevada, like at the Golden Trout Volcanic Field GTVF), the eruption rate, number of vents, and eruption volume is an order of magnitude less than at neighboring Basin and Range volcanic fields such as the Big Pine Volcanic Field (BPVF). To determine the factors that cause these differences in adjacent and contemporaneous volcanic fields, I sampled rocks from both fields …


Modelling And Observational Evidence For The Igneous Evolution Of The Elysium Volcanic Province On Mars, David Andrew Susko Jan 2017

Modelling And Observational Evidence For The Igneous Evolution Of The Elysium Volcanic Province On Mars, David Andrew Susko

LSU Master's Theses

A major knowledge gap exists on how eruptive compositions of a single martian volcanic province change over time. The Elysium Volcanic Province is a location of great geologic interest on Mars. Its predominantly Amazonian surface age (beginning 3.3 Ga), and its isolation in the northern hemisphere of Mars away from other volcano-tectonic regions, make it an ideal locale to investigate igneous compositions erupted during the most recent geologic period on Mars. Here, this work seeks to fill that gap by assessing the compositional evolution of Elysium as a major martian volcanic province in two related projects. The first project seeks …


Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern Mar 2016

Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern

Theses and Dissertations

Io, the most volcanically active body in the solar system, also has some of the tallest and steepest mountains. The mountains seem to be tectonic in origin, yet the methods of their formation have not been decisively constrained and their associations with volcanic paterae are yet unclear. We have compiled global spatial statistics on mountain dimensions and orientations, lineations attributed to structures, straight patera margins, and patera dimensions in order to better define their genetic relationships and the mechanisms forming each type of feature. Additionally, we have produced 4 regional structural maps of mountain complexes and have proposed tectonic histories. …


Geophysical Evidence For Mid-Crustal Magma Reservoirs In The Lassen Volcanic Region, California, Samantha Catherine Tavarez Nov 2015

Geophysical Evidence For Mid-Crustal Magma Reservoirs In The Lassen Volcanic Region, California, Samantha Catherine Tavarez

USF Tampa Graduate Theses and Dissertations

Regional-scale complete Bouguer gravity anomalies underlying the Lassen and Shasta -Medicine Lake regions in northern California and southern Oregon are associated with subduction of the Gorda plate beneath North America. These generally negative anomalies reflect where underplating has deepened to form the mantle wedge, and where subduction has given rise to a series of Quaternary volcanoes comprising the southernmost end of the Cascade range. Multiple conductive bodies were identified by Park and Ostos (2013) in their magnetotelluric (MT) study of the broader Lassen volcanic region. Their broadband and long period measurements were conducted along a 250 km profile spanning from …


Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson Nov 2015

Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson

Theses and Dissertations

Volcanoes are key indicators of a planet's internal structure, mechanics, and evolutionary history. Consequently, understanding the types and ages of volcanoes on a planet's surface is an important endeavor. In an attempt to better understand the relationship between morphometry and volcanic processes, we compared low-shield volcanoes on Syria Planum, Mars, with basaltic shields of the eastern Snake River Plain. We used 133 volcanoes on Syria Planum that are covered by Mars Orbiting Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) elevation data and 246 eSRP shields covered by the National Elevation Dataset (NED) for this comparison. Shields on Syria …


Contrasting Silicic Magma Series In Miocene-Pliocene Ash Deposits In The San Miguel De Allende Graben, Guanajuato, Mexico, Eric Christiansen, Bart Kowallis, Aaron Adams, Oscar Carranza-Castaneda, Wade Miller Jul 2015

Contrasting Silicic Magma Series In Miocene-Pliocene Ash Deposits In The San Miguel De Allende Graben, Guanajuato, Mexico, Eric Christiansen, Bart Kowallis, Aaron Adams, Oscar Carranza-Castaneda, Wade Miller

Bart J Kowallis

The San Miguel de Allende graben, Guanajuato, Mexico, contains numerous rhyolitic volcanic ash beds. Electron microprobe and x-ray fluorescence analyses of glass shards from 14 localities, combined with mineralogic, stratigraphic, radiometric, and paleomagnetic data, allow us to correlate the ash beds (and the intervening sedimentary strata and fossils), understand the timing of volcanism, date the age of extension, and better understand the tectonic and volcanic evolution of central Mexico. Our analyses reveal that at least six separate eruptions of rhyolitic ash occurred during the Late Miocene and Pliocene (5-3 Ma) while the San Miguel Allende basin was subsiding. The fallout …


Construction And Destruction Of Mont Pelée Volcano: Volumes And Rates Constrained From A Geomorphological Model Of Evolution, Aurélie Germa, Pierre Lahitte, Xavier Quidelleur Jul 2015

Construction And Destruction Of Mont Pelée Volcano: Volumes And Rates Constrained From A Geomorphological Model Of Evolution, Aurélie Germa, Pierre Lahitte, Xavier Quidelleur

School of Geosciences Faculty and Staff Publications

This study presents long‐term volumes and construction rates for the Mont Conil‐Mont Pelée volcano and rate estimates at which volcanic activity creates relief. An algorithm, ShapeVolc, is used to numerically model topographic surfaces. Volcano morphology is analyzed using current digital elevation model in combination with mapped geology to produce 10 paleotopographies at the end of four constructional stages and three destructional events. Volumes of each constructional stage were estimated at about 35.2 km3, 26.2 km3, 8.3 km3, and 2.5 km3 for a total cumulative erupted volume of 72.2 km3. We estimate …


The Geology Of Gökçeada (Çanakkale), Ramazan Sari, Ahmet Türkecan, Mustafa Dönmez, Şahset Küçükefe, Ümit Aydin, Öner Özmen Jun 2015

The Geology Of Gökçeada (Çanakkale), Ramazan Sari, Ahmet Türkecan, Mustafa Dönmez, Şahset Küçükefe, Ümit Aydin, Öner Özmen

Bulletin of the Mineral Research and Exploration

The geology and especially the magmatic rocks of Gökçeada, which is the biggest island of Turkey and located at 20 km’s west of Biga Peninsula, constitute the subject of this study. Late Ediacaran/ Early Paleozoic aged Çamlıca metamorphics which crop out with a tectonic uplift in a narrow area in northwest of Gökçeada are the oldest rocks of the island. Early Eocene aged Karaağaç Formation which is formed by submarine fan deposits unconformably overlies Çamlıca metamorphics. As for the Dağiçitepe volcanic member which is formed by rhyolitic lavas, tuff and tuffites emplaced into Karaağaç Formation cutting Çamlıca metamorphics is the …


Volcanism-Induced Karst Landforms And Speleogenesis, In The Ankarana Plateau (Madagascar). Hypothesis And Preliminary Research, Eric Gilli Jun 2014

Volcanism-Induced Karst Landforms And Speleogenesis, In The Ankarana Plateau (Madagascar). Hypothesis And Preliminary Research, Eric Gilli

International Journal of Speleology

The Ankarana is a limestone plateau in the northern part of Madagascar, where a cave system, more than 120 km long, has been explored. The plateau is bordered by volcanoes and is cut across by several canyons. An analysis of surface landforms and caves suggests that the karst genesis was probably initiated by volcanism beneath an impervious cover. Volcanic bulging and magma intrusions may have favored a basalt-limestone assimilation process and metamorphism. The ascent of deep volcanic fluids (CO2 and SO2) from magma degassing and from limestone metamorphism, may explain the speleogenesis. Once denuded, the karst evolved …


The Kimama Core: A 6.4 Ma Record Of Volcanism, Sedimentation, And Magma Petrogenesis On The Axial Volcanic High, Snake River Plain, Id, Katherine Elizabeth Potter May 2014

The Kimama Core: A 6.4 Ma Record Of Volcanism, Sedimentation, And Magma Petrogenesis On The Axial Volcanic High, Snake River Plain, Id, Katherine Elizabeth Potter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Snake River Plain (SRP) is one of the best-preserved examples of continental hotspot volcanis, with a continuous record of volcanism that extends over 16 Ma to the present. Yellowstone-Snake River Plain records the migration of plume-tail volcanism from inception at the Bruneau-Jarbridge caldera complex at 12.6 Ma to its present locus, under the Yellowstone Plateau.

Records kept by the Snake River Plain volcanic actions include rhyolite lavas and ignimbritesm minor coeval basalts, and an overlying veneer of younger basalts. The central SRP has received comparatively little attention in the past. The Kimama core hole was drilled as part of …


Ice Cores From The St. Elias Mountains, Yukon, Canada: Their Significance For Climate, Atmospheric Composition And Volcanism In The North Pacific Region, Christian Zdanowicz, David Fisher, Jocelyne Bourgeois, Mike Demuth, James Zheng, Paul A. Mayewiski, K Kreutz, Erich Osterberg, Kaplan Yalcin, Cameron P. Wake, Eric J. Steig, Duane Froese, Kumiko Goto-Azuma Feb 2014

Ice Cores From The St. Elias Mountains, Yukon, Canada: Their Significance For Climate, Atmospheric Composition And Volcanism In The North Pacific Region, Christian Zdanowicz, David Fisher, Jocelyne Bourgeois, Mike Demuth, James Zheng, Paul A. Mayewiski, K Kreutz, Erich Osterberg, Kaplan Yalcin, Cameron P. Wake, Eric J. Steig, Duane Froese, Kumiko Goto-Azuma

Dartmouth Scholarship

A major achievement in research supported by the Kluane Lake Research Station was the recovery, in 2001 –02, of a suite of cores from the icefields of the central St. Elias Mountains, Yukon, by teams of researchers from Canada, the United States, and Japan. This project led to the development of parallel, long (103 – 104 year) ice-core records of climate and atmospheric change over an altitudinal range of more than 2 km, from the Eclipse Icefield (3017 m) to the ice-covered plateau of Mt. Logan (5340 m). These efforts built on earlier work recovering single ice cores in this …


Spatial And Temporal Evolution Of The Volcanics And Sediments Of The Kenya Rift, Alexandria L. Guth Jan 2013

Spatial And Temporal Evolution Of The Volcanics And Sediments Of The Kenya Rift, Alexandria L. Guth

Dissertations, Master's Theses and Master's Reports - Open

New volumetric and mass flux estimates have been calculated for the Kenya Rift. Spatial and temporal histories for volcanic eruptions, lacustrine deposition, and hominin fossil sites are presented, aided by the compilation of a new digital geologic map. Distribution of volcanism over time indicates several periods of southward expansion followed by relative positional stasis. Volcanism occurs throughout the activated rift length, with no obvious abandonment as the rift system migrated. The main exception is a period of volcanic concentration around 10 Ma, when activity was constrained within 2° of the equator.

Volumes derived from seismic data indicate a total volume …


Geochemical And 40ar/39ar Constraints On The Evolution Of Volcanism In The Woodlark Rift, Papua New Guinea, Joseph Paul Catalano Aug 2012

Geochemical And 40ar/39ar Constraints On The Evolution Of Volcanism In The Woodlark Rift, Papua New Guinea, Joseph Paul Catalano

Earth & Environmental Sciences - Theses

The tectonic mechanisms producing Pliocene to active volcanism in eastern Papua New Guinea (PNG) have been debated for decades . In order to assess mechanisms that produce volcanism in the Woodlark Rift, we evaluate the evolution of volcanism in eastern PNG using 40Ar/39Ar thermochronology and whole rock geochemistry.

Active volcanism in southeastern Papua New Guinea occurs on the Papuan Peninsula (Mt. Lamington, Mt. Victory and Waiwa), in the Woodlark Rift (Dobu Island, SE Goodenough Island, and Western Fergusson Island), and in the Woodlark Basin . In the Woodlark Basin, seafloor spreading is active and decompression melting of the upper mantle …


Cenozoic Tectonic Evolution Of The Central Wassuk Range, Western Nevada, Usa, Benjamin E. Surpless Mar 2012

Cenozoic Tectonic Evolution Of The Central Wassuk Range, Western Nevada, Usa, Benjamin E. Surpless

Geosciences Faculty Research

The central Wassuk Range of western Nevada is ideally located to investigate the interplay of Basin and Range extension and Walker Lane dextral deformation on the margin of the Basin and Range province. To elucidate the Cenozoic evolution of the range, the author conducted geologic mapping, structural data collection and analysis, geochemical analysis of igneous lithologies, and geochronology. This research delineates a three-stage deformational history for the range. A ~15 Ma pulse of ENE-WSW directed extension at high strain rates (~8.7 Ma) was immediately preceded by the eruption of andesites and was accommodated by high-angle, closely spaced (1-2 km), east-dipping …


Cenozoic Volcanism Of The Caucasian Mobile Belt In Georgia, Its Geological-Petrological Peculiarities And Geodynamic Conditions, Bezhan Tutberidze Jan 2012

Cenozoic Volcanism Of The Caucasian Mobile Belt In Georgia, Its Geological-Petrological Peculiarities And Geodynamic Conditions, Bezhan Tutberidze

Turkish Journal of Earth Sciences

The Caucasian mobile belt is situated in the area of Late Cenozoic collision of the large Afro-Arabian and Eurasian lithospheric plates. Extensive volcanic activity in the Georgian part of the Caucasian mobile belt took place during the Late Miocene-Holocene. Five volcanic regions have been identified in Georgia; each of them reveals in a greater or lesser degree similarity of tectonic and magmatic processes. Volcanic products are represented by basaltic, doleritic, andesitic basaltic, andesitic dacitic, rhyolitic lavas and their pyroclastics with andesites and dacites prevailing. Using petrochemical and geochemical data the volcanics can be divided into two main rock groups: calc-alkaline …


Magma Chamber Processes At Mutnovsky Volcano, Russia, Kelly L. Robertson Dec 2011

Magma Chamber Processes At Mutnovsky Volcano, Russia, Kelly L. Robertson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is composed of two manuscripts about the evolution of Mutnovsky Volcano in Kamchatka, Russia. Mutnovsky has been active for the past approximately 80,000 years, during which there was the formation and subsequent eruption of four major stratocones. These four eruptive centers, named Mutnovsky I, II, III, and IV from oldest to youngest, have a range of erupted product compositions from basalt to dacite. The first major goal of this project was to investigate the melt source for Mutnovsky. Whole rock trace element and Nd, Sr, and Pb isotopic data were used to determine that the melt source was …


Geology Of The Caucasus: A Review, Shota Adamia, Guram Zakariadze, Tamar Chkhotua, Nino Sadradze, Nino Tsereteli, Aleksandre Chabukiani, Aleksandre Gventsadze Jan 2011

Geology Of The Caucasus: A Review, Shota Adamia, Guram Zakariadze, Tamar Chkhotua, Nino Sadradze, Nino Tsereteli, Aleksandre Chabukiani, Aleksandre Gventsadze

Turkish Journal of Earth Sciences

The structure and geological history of the Caucasus are largely determined by its position between the still-converging Eurasian and Africa-Arabian lithospheric plates, within a wide zone of continental collision. During the Late Proterozoic-Early Cenozoic, the region belonged to the Tethys Ocean and its Eurasian and Africa-Arabian margins where there existed a system of island arcs, intra-arc rifts, back-arc basins characteristic of the pre-collisional stage of its evolution of the region. The region, along with other fragments that are now exposed in the Upper Precambrian-Cambrian crystalline basement of the Alpine orogenic belt, was separated from western Gondwana during the Early Palaeozoic …


Interactions Between Human Activity, Volcanic Eruptions And Vegetation During The Holocene At Garua And Numundo, West New Britain, Png, William Boyd, Carol Lentfer, Jeffrey Parr Jul 2009

Interactions Between Human Activity, Volcanic Eruptions And Vegetation During The Holocene At Garua And Numundo, West New Britain, Png, William Boyd, Carol Lentfer, Jeffrey Parr

Jeffrey Parr

This paper reviews recent fossil phytolith analysis from wet tropical West New Britain (Papua New Guinea). The Holocene vegetation has been influenced by spatially and temporally diverse patterns of both prehistoric human settlement and catastrophic volcanic events. We have hypothesized different landscape responses and recovery pathways to events during the last six millennia. Phytolith sequences on the coastal lowlands, the Willaumez Peninsula, and nearby island of Garua provide details of vegetational change and human interactions at different landscape scales since c. 5900 cal yr B.P. During this period four major volcanic eruptions (c. 5900, 3600, 1700 and 1400 cal yr …


Geology Of The Southern Reveille Range, Nye County, Nevada, Matthew Alan Mckelvey May 2008

Geology Of The Southern Reveille Range, Nye County, Nevada, Matthew Alan Mckelvey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Reveille Range in central Nevada provides a unique window into the mid-Miocene geology and volcanology of the central Great Basin during the "ignimbrite flare up." Although faulted along its margins, the interior of the range is relatively undeformed thus preserving volcanic centers. The Reveille Range contains three mid-Miocene caldera complexes. Previous studies have identified the Goblin Knobs caldera (25.6 Ma) in the central Reveille Range and the caldera of northern Reveille Range (25.3 Ma) to the north. These calderas are completely filled with intracaldera tuffs. This study has identified a younger third caldera located in the southern part of …


Timing Of The Quaternary Elazığ Volcanism, Eastern Turkey, And Its Significance For Constraining Landscape Evolution And Surface Uplift, Ali̇ Seyrek, Rob Westaway, Malcolm Pringle, Sema Yurtmen, Tuncer Demi̇r, George Rowbotham Jan 2008

Timing Of The Quaternary Elazığ Volcanism, Eastern Turkey, And Its Significance For Constraining Landscape Evolution And Surface Uplift, Ali̇ Seyrek, Rob Westaway, Malcolm Pringle, Sema Yurtmen, Tuncer Demi̇r, George Rowbotham

Turkish Journal of Earth Sciences

The eastern part of the Anatolian plateau in eastern Turkey has experienced dramatic landscape evolution in the Late Cenozoic, surface uplift having been associated with the disruption of former lake basins and the development of the modern high-relief landscape, incised by the upper reaches of the River Euphrates and its major tributary, the Murat. Overall, the altitude of the plateau decreases gradually westward, and it has been assumed that uplift on any given timescale has varied regionally in a similar manner. However, using the Ar-Ar method, we have dated an episode of basaltic volcanism around the city of Elazığ to …


The Dikili-Çandarlı Volcanics, Western Turkey: Magmatic Interactions As Recorded By Petrographic And Geochemical Features, Zeki̇ye Karacik, Yücel Yilmaz, Julian A. Pearce Jan 2007

The Dikili-Çandarlı Volcanics, Western Turkey: Magmatic Interactions As Recorded By Petrographic And Geochemical Features, Zeki̇ye Karacik, Yücel Yilmaz, Julian A. Pearce

Turkish Journal of Earth Sciences

Located in the northwestern part of the Aegean region, Dikili-Çandarlı volcanic suite contains products representative for the western Anatolian Miocene volcanism. They can be divided into two main groups: the Dikili and the Çandarlı groups. The Dikili group is Early-Middle Miocene in age and consists mainly of pyroclastic rocks, andesitic-dacitic lavas, lava breccia, lahar flows and associated sedimentary rocks. The lavas contain disequilibrium phenocrysts assemblages. The Çandarlı group consists of Upper Miocene-Pliocene lava and sediment associations. The volcanic rocks consist mainly of rhyolitic domes and basaltic trachyandesite-basaltic andesite lavas erupted along the NW-SE- and NE-SW-trending fault systems; the faults controlled …