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Seismic Facies Mapping For Source Rock Distribution Of The Rakopi Formation In Deep-Water Taranaki Basin, New Zealand, Sidney W. Mahanay 2018 University of Arkansas, Fayetteville

Seismic Facies Mapping For Source Rock Distribution Of The Rakopi Formation In Deep-Water Taranaki Basin, New Zealand, Sidney W. Mahanay

Theses and Dissertations

The Taranaki Basin is located off the coast of the north island of New Zealand and is currently the only producing basin in New Zealand. Hydrocarbon accumulation in the Tui, Maari, and Maui fields is sourced to the Late Cretaceous and Paleogene units. Exploration of these units has extended from the continental shelf of the Taranaki Basin into the deep-water to the northwest. The Romney 3D survey and Romney–1 well are some the first public exploration projects to supply data from this area. The objective of this study is to estimate source rock quality and distribution of the Rakopi ...


The Transition From Sevier To Laramide Orogeny Captured In Upper-Plate Magmatic Structures, Eastern Transverse Ranges, Ca, Brody Friesenhahn 2018 Southern Methodist University

The Transition From Sevier To Laramide Orogeny Captured In Upper-Plate Magmatic Structures, Eastern Transverse Ranges, Ca, Brody Friesenhahn

Earth Sciences Theses and Dissertations

The onset of the Laramide orogeny is of great tectonic significance to the geologic history of the US, but the timing and nature of the shift between Sevier and Laramide tectonics remains enigmatic. The eastern Transverse Ranges of southern California provide the opportunity to observe the effects of Laramide tectonics on the mid-crust. Wide Canyon is a north/south-trending canyon in the northern Little San Bernardino Mountains of the eastern Transverse Ranges. Al-in-hornblende thermobarometry of Needy et al. (2009) yields a projected paleodepth depth of ~20 km for Wide Canyon where Cretaceous granitoids intrude metamorphic country rock of Proterozoic age ...


A Characterization Of Petrified And Mummified Wood From An Eocene Deposit In Mississippi, Nayeon Lee, Sungkwang Mun, Mark Horstemeyer, Stephen J. Horstemeyer, David J. Lang 2018 Mississippi State University

A Characterization Of Petrified And Mummified Wood From An Eocene Deposit In Mississippi, Nayeon Lee, Sungkwang Mun, Mark Horstemeyer, Stephen J. Horstemeyer, David J. Lang

The Proceedings of the International Conference on Creationism

This study experimentally investigates pieces of fossilized wood that include both mummified and petrified portions within the same pieces collected from the Red Hills Lignite Mine in Mississippi, USA. To the authors’ knowledge, having petrified and mummified regions within the same piece of wood has not been previously reported. Our study analyzes the chemical compositions, microstructures, and nanohardness to characterize the fossilized wood. The chemical analysis revealed that the composition of the mummified regions included mainly carbon, oxygen, and small amount of minerals indicating these regions were similar to currently growing wood, and the petrified regions included silicon and oxygen ...


Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman 2018 Pennsylvania State University, Mont Alto

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use in teaching ...


Hydrothermal Water-Rock Reaction Modeling With Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, Wy, Shanna Law 2018 Montana Tech

Hydrothermal Water-Rock Reaction Modeling With Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, Wy, Shanna Law

Graduate Theses & Non-Theses

Water-rock reactions at depth are the main control on aqueous hydrothermal chemistries of hot springs and other thermal features. Thermophilic microbes living in the hydrothermal system are a secondary control on aqueous hydrothermal chemistries and are expected to have increasing influence as spring temperatures decrease. The Rabbit Creek area of Yellowstone National Park (YNP) is an ideal case study for investigating the geologic and biologic controls on aqueous hydrothermal chemistries due to the proximity of the drill core Y-5 to geochemically diverse hydrothermal features (17.3⁰C to 92.2⁰C ± 0.1⁰C; field pH values 6.50 to 9.60 ± 0 ...


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, cave ...


Drip Water Measurements From Carlsbad Cavern: Implications Towards Paleoclimate Records Yielded From Evaporative-Zone Stalagmites, Victor J. Polyak, Jessica B.T. Rasmussen, Yemane Asmerom 2018 University of New Mexico

Drip Water Measurements From Carlsbad Cavern: Implications Towards Paleoclimate Records Yielded From Evaporative-Zone Stalagmites, Victor J. Polyak, Jessica B.T. Rasmussen, Yemane Asmerom

International Journal of Speleology

Stalagmites can host numerous potential climate proxies (stable and radiogenic isotopes, trace elements, annual and non-annual banding, grayscale, growth hiatuses, mineral assemblage). Reproducibility and/or integration of proxy results between one or more stalagmites will become increasingly important, and ideally, climate records generated by multiple stalagmites from the same cave or cave room are expected to be near-identical. The reality is that stalagmites from the same cave room can yield differing results to some degree, especially in cave environment zones that are evaporative. Our drip water study in an evaporative shallow-depth cave environment in Carlsbad Cavern shows that adjacent drip ...


An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham el-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan 2018 Chapman University

An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study considers the various factors that regulate nutrients supply in the Red Sea. Multi-sensor observation and reanalysis datasets are used to examine the relationships among dust deposition, sea surface temperature (SST), and wind speed, as they may contribute to anomalous phytoplankton blooms, through time-series and correlation analyses. A positive correlation was found at 0–3 months lag between chlorophyll-a (Chl-a) anomalies and dust anomalies over the Red Sea regions. Dust deposition process was further examined with dust aerosols’ vertical distribution using satellite lidar data. Conversely, a negative correlation was found at 0–3 months lag between SST ...


An Investigation Of Hydrothermal Veins Along The Foy Offset Dyke, Sudbury Impact Structure, Ontario, Sarah Ann CoDyre 2018 The University of Western Ontario

An Investigation Of Hydrothermal Veins Along The Foy Offset Dyke, Sudbury Impact Structure, Ontario, Sarah Ann Codyre

Electronic Thesis and Dissertation Repository

A multi-stage hydrothermal system is related to the 1.85 Ga Sudbury impact structure. This system began in the Sudbury Igneous Complex (SIC) and radiated outward along the offset dykes. Through the combination of orientation measurements of veins in the field, petrography and geochemistry of these veins, this study has determined that there are four types of hydrothermal epidote-quartz veins categorized by their orientation, petrography and geochemistry. This study discovered that there are general trends with increasing distance from the SIC along the Foy Offset Dyke. From this it can be concluded that this is in fact SIC-driven hydrothermal event ...


Unusual Internal Structure Of Cm-Sized Coldwater Calcite: Weichselian Spars In Former Pools Of The Zinnbergschacht Cave (Franconian Alb/Se Germany), Detlev K. Richter, Rolf D. Neuser, Martin Harder, Hardy Schabdach, Denis Scholz 2018 Ruhr-Universität Bochum

Unusual Internal Structure Of Cm-Sized Coldwater Calcite: Weichselian Spars In Former Pools Of The Zinnbergschacht Cave (Franconian Alb/Se Germany), Detlev K. Richter, Rolf D. Neuser, Martin Harder, Hardy Schabdach, Denis Scholz

International Journal of Speleology

The investigation of the internal structure of calcite crystals is a new focus in speleothem science, especially in the range of crystallization temperatures close to 0°C. Recently found calcite spars from Zinnbergschacht Cave of the Franconian Alb (SE Germany) are ideal for multi-method investigation. The elongated calcites (up to 6 cm in length) with three to six lateral faces and basal triangular faces at the ends are observed in collapse-zones in the cave. 230Th/U-ages of 38.9 ka suggest formation during the periglacial Weichselian, between the Scandinavian and Alpine Glaciations. The δ18O and δ13 ...


Iodine To Calcium Ratios In Marine Carbonates As An Indicator Of Oxygen Levels, Angela Stahl 2018 University of Rhode Island

Iodine To Calcium Ratios In Marine Carbonates As An Indicator Of Oxygen Levels, Angela Stahl

Senior Honors Projects

ANGELA STAHL (Marine Biology)

Iodine to Calcium Ratios in Marine Carbonates as an Indicator of Oxygen Levels

Sponsor: Rebecca Robinson (Graduate School of Oceanography)

The Earth goes through natural cycles of warm and cool periods. In the past,

warmer oceans during interglacial periods have been shown to hold less oxygen

in their waters compared to cooler, glacial oceans. For this research, we are

studying an area in the Eastern Tropical Pacific where it is known to have

variable concentrations of dissolved oxygen in the waters due to the influence of

the climate. Oxygen is a vital component for most organisms ...


Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher 2018 Old Dominion University

Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have been found to influence its cycling and longevity in the environment. Dissolution via leaching may be the main control on loss processes such as microbial or abiotic oxidation, mineral sorption, or export to aquatic systems. Yet, little is known about the controls on pyrogenic dissolved organic matter (pyDOM) generation or composition. Here, the yield and composition of pyDOM generated through batch leaching of a thermal series of oak and grass biochars, as well as several non-pyrogenic reference materials, was compared ...


Open Ocean Vs. Continentally-Derived Iron Cycles Along The Neoarchean Campbellrand-Malmani Carbonate Platform, South Africa, Suemeyya Eroglu, Ronny Schoenberg, Sakura Pascarelli, Nicolas J. Beukes, Ilka C. Kleinhanns, Elizabeth D. Swanner 2018 Iowa State University

Open Ocean Vs. Continentally-Derived Iron Cycles Along The Neoarchean Campbellrand-Malmani Carbonate Platform, South Africa, Suemeyya Eroglu, Ronny Schoenberg, Sakura Pascarelli, Nicolas J. Beukes, Ilka C. Kleinhanns, Elizabeth D. Swanner

Geological and Atmospheric Sciences Publications

The deposition of large amounts of mixed-valence Fe minerals in iron formations during the Archean and Paleoproterozoic indicates that the Fe(II)aq (aqueous) content of coeval anoxic seawater was likely several hundred μM, compared to ca. 1 to 20 nM of the modern oxygenated ocean. It has been suggested that oxygen production along shallow marine continental shelves, which probably started several hundred million years before the rise of atmospheric oxygen, effectively oxidized Fe(II)aq from deeper seawater and removed it as Fe(III)ppt(poorly soluble precipitates). However, the reconstruction of the marine Fe cycle during the Archean ...


Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga 2018 Western Kentucky University

Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga

Masters Theses & Specialist Projects

An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were ...


Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna 2018 Wesleyan University

Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna

Melissa Luna

No abstract provided.


Study On The Surface Features Of Preg-Robbing Carbonaceous Matter During Oxidation Treatment, Mana Pourdasht 2018 The University of Western Ontario

Study On The Surface Features Of Preg-Robbing Carbonaceous Matter During Oxidation Treatment, Mana Pourdasht

Electronic Thesis and Dissertation Repository

Carbonaceous gold ores have the ability to adsorb gold (I) cyanide from leach solutions during processing. This phenomenon, known as preg-robbing, is responsible for poor recoveries as the carbonaceous materials of the ore compete with activated carbon used during the leaching and adsorption phase of processing. Chemical oxidation of carbonaceous materials by different reagents has been utilized to investigate and compare the mechanism of Au (CN)2 adsorption onto carbonaceous materials prior to and following the treatment.

The procedure for characterization of the carbonaceous materials (plain and modified) in the sample combines the use of several analytical techniques and test ...


Oxic Fe(Iii) Reduction Could Have Generated Fe(Ii) In The Photic Zone Of Precambrian Seawater, Elizabeth D. Swanner, Markus Maisch, Wenfang Wu, Andreas Kappler 2018 Iowa State University

Oxic Fe(Iii) Reduction Could Have Generated Fe(Ii) In The Photic Zone Of Precambrian Seawater, Elizabeth D. Swanner, Markus Maisch, Wenfang Wu, Andreas Kappler

Geological and Atmospheric Sciences Publications

Many marine Precambrian iron formations (IF) record deep anoxic seawater enriched in Fe(II) (i.e. ferruginous) overlain by mildly oxygenated surface water. This is reflected by iron-rich sediments forming in deep basins, and relatively iron-poor sediments forming in shallow, sunlit waters. Such an iron gradient is often interpreted as a redox interface where dissolved Fe(II) was oxidized and precipitated as Fe(III)-bearing minerals. As such, sedimentary iron enrichments are proxy to the progressive oxidation of the oceans through geological time. However, this interpretation is founded on the assumption that Fe(II) could not persist within an oxygenated ...


Calcium Isotopes In Natural And Experimental Carbonated Silicate Melts, Matthew Maloney 2018 The University of Western Ontario

Calcium Isotopes In Natural And Experimental Carbonated Silicate Melts, Matthew Maloney

Electronic Thesis and Dissertation Repository

The calcium stable isotopic compositions of mantle-sourced rocks and minerals were investigated to better understand the carbon cycle in the Earth’s mantle. Bulk carbonatites and kimberlites were analyzed to identify a geochemical signature of carbonatite magmatism, while inter-mineral fractionation was measured in co-existing Ca-bearing carbonate and silicate minerals. Bulk samples show a range of composition deviating from the bulk silicate Earth δ44/40Ca composition indicating signatures of magmatic processes or marine carbonate addition to source materials. Δ44/40Cacarbonate-silicate values range from -0.55‰ to +1.82‰ and positively correlate with Ca/Mg ratios in ...


Global Seawater Redox Trends During The Late Devonian Mass Extinction Detected Using U Isotopes Of Marine Carbonates, David Allen White 2018 University of New Mexico

Global Seawater Redox Trends During The Late Devonian Mass Extinction Detected Using U Isotopes Of Marine Carbonates, David Allen White

Earth and Planetary Sciences ETDs

The Late Devonian extinction ranks as one of the ‘big five’ Phanerozoic extinctions affecting up to 80% of marine species and occurred during five distinct pulses spanning /or widespread marine anoxia. We test the marine anoxia hypothesis by analyzing uranium isotopes (δ238U) across a ~7 My interval of well-dated Upper Devonian marine carbonates from the Devil’s Gate Limestone in Nevada, USA.

The measured δ238U curve shows no co-variation with local anoxic facies, water-depth dependent facies changes, redox-sensitive metals, TOC, or diagnostic elemental ratios indicating the δ238U curve was not controlled by local depositional ...


Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops 2018 Chinese Academy of Sciences

Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops

Faculty Publications in the Biological Sciences

Global change-induced litter decomposition strongly affects the carbon (C) and nitrogen (N) dynamics in grassland ecosystems. However, few studies show the interactive effects of global change factors on litter and root decomposition. We conducted a four-year grassland field experiment to examine the quality and decomposition of litter and root in a three-factorial experiment with elevated CO2, increased N deposition, and plant species richness. We found that elevated CO2 decreased the litter N content and root lignin content. N addition increased the root N content and decreased the litter lignin content. Increasing plant richness decreased the N and lignin ...


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