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Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom 2021 Dartmouth College

Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom

Other Staff Materials

Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other …


Diffusional Fractionation Of Helium Isotopes In Silicate Melts, Haiyang Luo, Bijaya Karki, Dipta B. Ghosh, Huiming Bao 2021 Louisiana State University

Diffusional Fractionation Of Helium Isotopes In Silicate Melts, Haiyang Luo, Bijaya Karki, Dipta B. Ghosh, Huiming Bao

Faculty Publications

Estimating Helium (He) concentration and isotope composition of the mantle requires quantifying He loss during magma degassing. The knowledge of diffusional He isotope fractionation in silicate melts may be essential to constrain the He loss. Isotopic mass dependence of He diffusion can be empirically expressed as D3He/D4He = (4/3)^β, where D is the diffusivity of a He isotope. However, no studies have reported any β values for He in silicate melts due to technical challenges in both experiments and computations. Here, molecular dynamics simulations based on deep neural network potentials trained by ab initio data …


Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll 2021 University of Oviedo, Spain

Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll

International Journal of Speleology

Because they can archive a variety of geochemical proxies and be precisely and accurately dated with the U-Th decay series chronometer, stalagmites are widely used for paleoclimate reconstructions. However, limitations in the use of this chronometer arise because U-Th dating is analytically time consuming, expensive, and requires a relatively large sample size. These limitations restrict the number of absolute dates usually obtained, which can result in significant uncertainties in the age model and inhibit the ability to archive high resolution records of environmental variability, particularly in those stalagmites where there are variations in growth rate not constrained by U-Th dates. …


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, Lorenzo Tavazzani 2021 Southern Methodist University

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, Lorenzo Tavazzani

Earth Sciences Theses and Dissertations

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 …


Geochemistry Of Phosphatic Nodules As A Tool For Understanding Depositional And Taphonomical Settings In A Palaeolithic Cave Site (San Teodoro, Sicily), Gerlando Vita, Vittorio Garilli, Mirko Andrea Vizzini, Renato Giarrusso, Angelo Mulone, Massimiliana Pinto Vraca, Valeria La Parola, Pierluigi Rosina, Laura Bonfiglio, Luca Sineo 2021 Universitat Rovira I Virgili Tarragona, Spain

Geochemistry Of Phosphatic Nodules As A Tool For Understanding Depositional And Taphonomical Settings In A Palaeolithic Cave Site (San Teodoro, Sicily), Gerlando Vita, Vittorio Garilli, Mirko Andrea Vizzini, Renato Giarrusso, Angelo Mulone, Massimiliana Pinto Vraca, Valeria La Parola, Pierluigi Rosina, Laura Bonfiglio, Luca Sineo

International Journal of Speleology

Interpreting depositional settings of cave sites is generally problematic, especially in absence of paleontological/archaeological evidence. This is the case of some deposits at San Teodoro Cave (Sicily), a key site for the Mediterranean Palaeolithic. In a stratigraphic level interrupted by a carbonatic concretion, phosphatic nodules are present only in the part enclosed between the concretion and the cave wall. The discovery of these nodules combined with the punctual lack of fossils had initially suggested an erosion phenomenon and subsequent formation of nodules at a vadose level. Here we show the usefulness of an integrated, geochemical-paleoecological approach in defining stratigraphy and …


Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato 2021 Louisiana State University and Agricultural and Mechanical College

Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato

LSU Master's Theses

The movement of water through soil is preferential and heterogeneous. Subsurface interactions between mobile flows and the soil matrix are not uniform and are therefore difficult to predict through time and space. The use of stable isotopes of hydrogen (2H) and oxygen (18O) as conservative tracers of water movement is improving understanding of soil hydrological processes, yet field-scale observations of isotopic variability remain scarce despite implications for identifying dominant hydrologic processes. We sampled two adjacent soils at a ridge-swale topography floodplain forest to determine soil water isotopic variability at a 20 cm depth resolution in soils …


Sorption Of Metals At The Barite (001)-Water Interface, Inva Braha 2021 City University of New York (CUNY)

Sorption Of Metals At The Barite (001)-Water Interface, Inva Braha

Student Theses

Abstract

Ion desorption processes control the retention of ions, such as Pb2+, at barite surfaces, whereas ion adsorption processes are a likely initial step in the incorporation of divalent cations, such as Sr2+ and Pb2+, into barite. Based on previous studies on samples dominated by flat terraces with relatively few defects, Sr2+ and Pb2+ adsorb and incorporate at the barite (001)-water interface (Bracco et al., 2019; Bracco et al., 2020). Here, I measured how susceptible lead (Pb) is to desorption and the role surface variability plays in its sorption behavior. First, I measured …


Laboratory Capabilities, University of North Dakota. Energy and Environmental Research Center 2021 University of North Dakota

Laboratory Capabilities, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Energy & Environmental Research Center’s laboratory capabilities including reservoir characterization, organic geochemistry, fluid sampling, and material analysis. A list of publications and laboratory information is also included.


Palynology And Paleoclimatology Of The Chicxulub Impact Crater In The Early Paleogene, Vann Smith 2021 Louisiana State University and Agricultural and Mechanical College

Palynology And Paleoclimatology Of The Chicxulub Impact Crater In The Early Paleogene, Vann Smith

LSU Doctoral Dissertations

At the end of the Cretaceous Period, a large bolide impacted the Earth and formed the Chicxulub impact crater in the Yucatán Peninsula, Mexico. In 2016, International Ocean Discovery Program (IODP) Expedition 364 Site M0077 drilled into the buried peak ring of the crater, recovering a marine Paleocene to early Eocene post-impact section deposited on top of the impact breccia. Palynological analysis of 195 samples from the post-impact section has yielded the first pre-Holocene vegetational record from inside the Chicxulub impact crater and the first palynological record of the recovery of life following the end-Cretaceous mass extinction from inside the …


Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher 2021 Duquesne University

Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher

Electronic Theses and Dissertations

Between January 2011 and March 2021 oil and gas wells in Pennsylvania produced

305,637,795 barrels of liquid waste and 6,992,957 tons of solid waste with the majority from

Marcellus Shale unconventional wells. This waste is not considered hazardous and over 89% of

the solid waste generated by unconventional and conventional oil and gas extraction has been

disposed of in landfills over the past decade. This study examined trends in the quantity of waste

produced and methods of disposal. Landfills accepting this waste were identified and their

general method of leachate treatment, using onsite facilities or offsite at wastewater treatment

plants, …


Geology Of The Clairmont Springs 7.5-Minute Quadrangle And Geochronology Of The Alabama Blue Ridge, Adelie Ionescu 2021 Missouri State University

Geology Of The Clairmont Springs 7.5-Minute Quadrangle And Geochronology Of The Alabama Blue Ridge, Adelie Ionescu

Graduate Theses/Dissertations

The Alabama Blue Ridge (USA) of the southern Appalachians contains metamorphic rocks and structures associated with island arc accretion and continent-continent collision that record the Acadian and Alleghenian orogenies. The western Blue Ridge is underlain by Cambrian to Mississippian, clastic and carbonate, low-grade, greenschist facies metamorphic Talladega belt that formed outboard from the Alabama promontory or along the Laurentian margin. The eastern Blue Ridge contains the Neoproterozoic to Paleozoic, lithologically diverse, high grade, middle to upper amphibolite facies Ashland Supergroup. Geologic mapping of the Clairmont Springs 7.5- minute quadrangle unveils tectonic relationships between the eastern and western Blue Ridge and …


Re-Evaluation Of The First Metamorphic P-T Path Using Quig Barometry And Equilibrium Thermodynamics, Sam Couch 2021 Boise State University

Re-Evaluation Of The First Metamorphic P-T Path Using Quig Barometry And Equilibrium Thermodynamics, Sam Couch

Boise State University Theses and Dissertations

Quartz in garnet (“QuiG”) barometry is a relatively new technique that uses physical properties of minerals to estimate the pressure of garnet nucleation and growth history independent of chemical equilibrium. QuiG barometry was used to determine pressures of garnet growth and compared to thermodynamically calculated P-T conditions for two samples (FH-1M and Z3H) from the Lower Shieferhülle (Formation), Tauern Window, Austria. FH-1M was the first sample for which a P-T path was calculated through inversion of chemical zoning in garnet (Selverstone et al., 1984). Mineral Assemblage Diagrams (MADs) and geothermobarometric techniques were used to determine P-T conditions for garnet nucleation …


Understanding The Chemical Weathering Rate And Element Mobility Of Soils: Using U-Series, Nd-Sr Isotopes Ree And Quantum Chemistry Computational Simulation, Jiye Guo 2021 University of Texas at El Paso

Understanding The Chemical Weathering Rate And Element Mobility Of Soils: Using U-Series, Nd-Sr Isotopes Ree And Quantum Chemistry Computational Simulation, Jiye Guo

Open Access Theses & Dissertations

Soil played as the central role in the interaction of biosphere, hydrosphere, lithosphere and atmosphere and is the heart of earth's critical zone study. The weathering and element mobility of soils have drawn considerable attention in soil studies since the complexity of these processes and the critical influence towards the earth and humanity, e.g., the global carbon cycles and fertilization. However, the interaction between soils and various factors including precipitation, bedrock ages, altitude is not well understood. Basse-Terre Island at French Guadeloupe, a small volcanic tropical island that has steep environmental gradients of bedrock ages, topography and precipitation, can be …


Develop A Multi-Functional Green Pervious Concrete (Mgpc) Pavement With Polycyclic Aromatic Hydrocarbons (Pahs) Removal Function., Hong Shang 2021 University of Louisville

Develop A Multi-Functional Green Pervious Concrete (Mgpc) Pavement With Polycyclic Aromatic Hydrocarbons (Pahs) Removal Function., Hong Shang

Electronic Theses and Dissertations

Stormwater runoff induced Polycyclic Aromatic Hydrocarbons (PAHs) contaminant increasingly imperils the groundwater quality and the sustainable development of human society due to the potential carcinogenic risks. Pavement can be considered as the first line of defense for contaminant removal of the stormwater runoff. New construction materials with stormwater runoff quantity and quality control are in urgent demand for updating the existing pavement system. An innovative material called Multi-functional Green Pervious Concrete (MGPC) was developed in the department of Civil and Environmental Engineering at University of Louisville. This material uses organoclay as the amendment to enhance the PAHs removal capacity of …


Reconstructing 1856-7 California Mining Patterns From Placer Gold Recovered From The Wreck Of The Ss Central America, Kathryn Ruth VonSydow 2021 California State University - San Bernardino

Reconstructing 1856-7 California Mining Patterns From Placer Gold Recovered From The Wreck Of The Ss Central America, Kathryn Ruth Vonsydow

Electronic Theses, Projects, and Dissertations

The discovery of the SS Central America 1857 shipwreck site provides a time capsule that can be used to address questions about the spatial and temporal patterns of placer mining in California during the peak of the gold rush. Samples of placer gold in the collections of museums and private individuals can have uncertain pedigree due to labeling issues and alterations by cleaning and curatorial processes. However, placer gold from the 1857 shipwreck could only have come from the Mother Lode Country of California, as no other gold districts had yet been found in western North America. I compared the …


New Perspectives On Prolific And Voluminous Rhyolite Volcanism Of The Mahogany Mountain--Three Fingers Rhyolite Field, Eastern Oregon, Robert Andrew Jackson 2021 Portland State University

New Perspectives On Prolific And Voluminous Rhyolite Volcanism Of The Mahogany Mountain--Three Fingers Rhyolite Field, Eastern Oregon, Robert Andrew Jackson

Dissertations and Theses

Voluminous silicic volcanism of the Mahogany Mountain--Three Fingers rhyolite field (MM--TFrf) is spatially and temporally associated with mid-Miocene flood basalts of the Columbia River Basalt province. Early studies of the area advocated for a two-caldera model consisting of the Mahogany Mountain and the slightly younger Three Fingers caldera with pre- and post-caldera effusive rhyolite eruptions. Although close in time, the calderas were thought to be spatially offset producing the tuff of Leslie Gulch and the tuff of Spring Creek. Finding that the tuff of Spring Creek, that is exposed in Leslie Gulch, is an altered product of the tuff of …


Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci 2021 University of New Mexico

Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci

Earth and Planetary Sciences ETDs

Melting and differentiation are fundamental to early solar system evolution on planetary bodies that accreted enough material to heat up radioactively or through impacts and breach their solidi. Partially and fully melted material is present in the meteorite record in the form of primitive achondrites and achondrites, which are fragments of planetesimals that underwent heating events in the first few million years of solar system history. Although the vast majority of this material is mafic or ultramafic, new evolved samples, recovered in the last few decades, are pushing the petrologic and geochemical boundaries of planetesimal melting, differentiation, and crust formation. …


Computer Simulations Of Diffusional Isotope Effects And Dynamical Properties Of Silicate Melts, Haiyang Luo 2021 Louisiana State University

Computer Simulations Of Diffusional Isotope Effects And Dynamical Properties Of Silicate Melts, Haiyang Luo

LSU Doctoral Dissertations

Silicate melts have served as transport agents in the chemical and thermal evolution of Earth. Diffusional isotope effect in silicate melts is the key to interpret isotope variations in lots of geological samples. Isotopic mass dependence of diffusion is commonly expressed as (Di/Dj)=(mj/mi)^β, where Di and Dj are diffusion coefficients of two isotopes whose masses are mi and mj. However, how the dimensionless empirical parameter β depends on temperature, pressure, and composition remains poorly constrained. Viscosity and electrical conductivity are two fundamental dynamical properties of silicate melts needed to constrain melt distribution in Earth's interior but remain unclear for most …


Barriers To And Uncertainties In Understanding And Quantifying Global Critical Mineral And Element Supply, Brian A. McNulty, Simon M. Jowitt 2021 University of Nevada, Las Vegas

Barriers To And Uncertainties In Understanding And Quantifying Global Critical Mineral And Element Supply, Brian A. Mcnulty, Simon M. Jowitt

Geoscience Faculty Research

The critical minerals and elements are natural substances that are essential to modern life but have insecure supply. This lack of a secure supply clashes with the increasing importance of these elements, especially given their use in technologies needed to reduce global CO2 emissions and mitigate against anthropogenic climate change. In this contribution we review the by-product nature of the critical minerals and elements and the inherant uncertainties in reported critical mineral and element annual production as well as the relationships between these commodities and main-product metals and associated concentrates. We explore the geological and geographical barriers to critical mineral …


Geological And Geochemical Analysis Of Phosphorus Bearing Minerals And Natural Glasses On Earth And In Meteorites: Implications Of The Origin Of Life, Tian Feng 2021 University of South Florida

Geological And Geochemical Analysis Of Phosphorus Bearing Minerals And Natural Glasses On Earth And In Meteorites: Implications Of The Origin Of Life, Tian Feng

USF Tampa Graduate Theses and Dissertations

Phosphorus is a key element in biogenic molecules and the mineral schreibersite is a major reactive phosphorus source for organic compounds on the prebiotic Earth. In this dissertation, a suite of reactions of phosphorus species, which originate from schreibersite minerals on chondrite meteorites and on the early Earth, have been studied to determine the intermediate geochemical pathways between phosphides and common minerals on meteorites and on the early earth.

I first investigated a unique blue fulgurite that was studied to clarify if this blue color was caused by rich phosphorus content, as has been reported for impact glasses that also …


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