Improving The Hydrological Analysis Of Groundwater Flow Paths By Integrating Geochemical And Physical Characteristics Of A Highly Fractured Aquifer System To Create Sustainable Use Of Groundwater In A Climate With Projected Drying Trends., Marsha K. Allen

Doctoral Dissertations

Improving the hydrological analysis of groundwater flow paths by integrating geochemical and physical characteristics of a highly fractured aquifer system to create sustainable use of groundwater in a climate with projected drying trends. Precipitation over Caribbean islands has decreased steadily since the 1950's, which has led to severe drought conditions. The most recent Pan-Caribbean Drought occurred from 2013 to 2016. Climate models predict that drying trends are expected to continue and become more severe over time as precipitation decreases and temperatures rise. In addition, evaporation rates on these islands are expected to increase by ~15-17%, contributing to the drought. Though …

Fundamental Controls On The Water Cycle In Arid Environments: A Mechanistic Framework For Spatiotemporal Connectivity Between Hydroclimate And Groundwaters In The Dry Andes, Brendan J. Moran

Doctoral Dissertations

There remain many persistent uncertainties regarding fundamental aspects of natural water cycles in arid mountainous regions, the Dry Andes of South America represents one of the most extreme examples of these environments on the Planet. Deep water tables (>100 meters), long groundwater transit times and distances (>100 years, 10-100 kilometers), limited and infrequent rainfall, remote and difficult to access terrain, and complex salar/evaporite hydrogeology common in these environments make reliable monitoring of these hydrological systems particularly difficult. As a result, major gaps remain in our understanding of critical aspects of the water cycle such as recharge and evaporation …

Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand

Masters Theses

The rise and demise of mountain belts, caused by growth, modification, or removal of the continental lithosphere are fundamental processes that influence almost all Earth systems. Understanding the nature, timing, and significance of active processes in the creation and evolution of modern mountain belts is challenged by a lack of middle crustal and lower crustal exposures. Analogues can be found in ancient orogens, whose deeply eroded roots offer a window into deeper processes, yet this record is complicated by overprinting events and complex deformational histories. Research presented herein constrains the tectonic history of multistage Appalachian Orogen, type locality of the …

Magnetite Mineralization Of The Hammondville Pluton: Poly-Phase Kiruna Type Iocg Magnetite-Apatite Deposits In The Lyon Mountain Granite, Phillip Geer

Masters Theses

Recent mapping of the Eagle Lake Quadrangle, NY, coupled with whole-rock geochemistry and microscopy has offered insight into the petrogenesis of the magnetite-apatite deposits of the Hammondville mining district in the eastern Adirondack Mountains. This study provides insight into the magmatic history of the ca. 1060-1050 Ma Lyon Mountain Granite (Hammondville Pluton) which is intimately related to, and hosts the deposits in this area. Magnetite seams are commonly surrounded by well layered magnetite gneiss, which typically parallel the seams, although in some outcrops appear to be slightly truncated by them. Mineralization is generally concordant with the weak layering found throughout …

Seeing Through The Ottawan Overprint, Adirondack Mtns., Ny: Integrating Microstructural Analysis, Geothermobarometry, And In-Situ Monazite Petrochronology, Justin Mistikawy

Masters Theses

Integrating field observation with petrochronology is critical for understanding the tectonometamorphic evolution of the North American Grenville Province. Despite methodological advances in geothermobarometry and geochronology, incorporating these data into larger models of the Adirondack Mountains remains particularly challenging due to the presence of multiple generations of deformation, primarily related to the ca. 1190 – 1140 Ma Shawinigan and ca. 1090 – 1020 Ma Ottawan Orogenies (McLelland et al.,2013). The Rock and Bear Ponds area is a dome of tight-to-isoclinally folded metapelites in structural contact with orthogneiss. Fold generations are orthogonal and partitioned such that the northern area is dominated by …

Data For "Hydrogeologic And Geochemical Distinctions Within Freshwater Brine Systems In Salar Environments", Lee Ann Munk, David F. Boutt, Brendan Moran, Sarah Mcknight, Jordan Jenckes

Data and Datasets

All chemistry and striontium isotope data for the study, "Hydrogeologic and Geochemical Distinctions within Freshwater Brine Systems in Salar Environments".

Petrogenesis Of Basaltic Lavas In Iceland And The Springerville Volcanic Field, U.S.A.: The Influence Of Tectonic Setting, Depth Of Melting And Volatiles, Marissa Mnich

Doctoral Dissertations

Icelandic basalts were long thought to be low in water (e.g. Gunnarsson et al., 1998), but more recent studies suggest that hotspots, like the Iceland mantle plume, may be a source of hydrous basaltic melts (Nichols et al., 2002). To explore a possible link between location, volatile concentration and resulting petrogenetic implications, samples were collected from eleven volcanic centers throughout Iceland. Water concentrations were measured in melt inclusions and phenocrysts using Fourier transform infrared (FTIR) spectroscopy. Results for a subset of samples indicate variable water in melt inclusions ranging from approximately 50 ppm to over 3000 ppm. Samples from southwestern …

Arctic And North Atlantic Paleo-Environmental Reconstructions From Lake Sediments, Gregory A. De Wet

Doctoral Dissertations

ABSTRACT

Petrogenesis And Concentric Zonation Of The Belchertown Intrusive Complex, West-Central Massachusetts, Karen June Van Wagner

Masters Theses

The Belchertown Intrusive Complex is a ~164 km2 Devonian pluton that intruded Paleozoic metasedimentary and metavolcanic rocks in west-central Massachusetts. Intrusion of the pluton was synchronous with Acadian deformation (Ashwal, 1974). The complex is concentrically zoned, with a core of orthopyroxene-biotite monzodiorite, a middle zone of clinopyroxene-hornblende-biotite granodiorite, and an outermost zone of hornblende-biotite granodiorite. Zoning from a more to less hydrous mineral suite from the outside to the inside of the pluton led Ashwal (1974) to suggest that metamorphic hydration most strongly affected the outermost zones of the complex. Basaltic inclusions occur most commonly near the edges of …

Metamorphic And Structural Control Of Magnetism Within The Lower Continental Crust, Northern Saskatchewan, Canada, Jeffrey R. Webber

Doctoral Dissertations

The linking of geophysical information to tectonometamorphic processes holds great potential for the surveying of vast remote areas of the planet and may allow for the transcendence of observational scales. Investigations concerning magnetic properties of the lower continental crust can reveal an incredible wealth of information concerning the conditions of metamorphism, regional extent of deformation, and controls on the magnetic architecture of the lithosphere. This dissertation presents three contributions aimed at the integration of petrology, structural geology, and rock magnetism in order to investigate the magnetic nature of the lower continental crust, constrain tectonometamorphic processes at the regional scale in …

Geochemical Attributes Of Hydraulically Active Fractures And Their Influence On Groundwater Quality, Amy L. Hudson

Doctoral Dissertations

This study utilized discrete interval diffusion sampling of a fractured bedrock well completed in schist to investigate if a natural weathering signal can be used to identify hydraulically active fractures. The open borehole well MFS-1, is the focus of the study, which is in close proximity to the recharge zone making it ideal for testing the hypotheses of this study. The hydraulically active fractures of Well MFS-1 were identified, and the dominant mixing force of the water column of the well was determined to be thermal convection in the upper portion of the well and upward gradients. The isotopic data …

Micropaleontology And Isotope Stratigraphy Of The Upper Aptian To Lower Cenomanian (~114-98 Ma) In Odp Site 763, Exmouth Plateau, Nw Australia, Ali Alibrahim

Masters Theses

The biostratigraphy and isotope stratigraphy of the upper Aptian to lower Cenomanian interval including oceanic anoxic events OAE1b, 1c and 1d are investigated in ODP Site 763, drilled on the Exmouth Plateau offshore northwest Australia. Benthic foraminifera suggest that Site 763 was situated in outer neritic to upper bathyal water depths (~150-600 m). OAEs of the Atlantic basin and Tethys are typically associated with organic carbon-rich black shales and δ¹³C excursions. However, OAEs at this high latitude site correlate with ocean acidification and/or pyrite formation under anoxic conditions rather than black shales. Ocean acidification maybe responsible for sporadic …

Sources Of Water And Solutes To The Salar De Atacama, Chile: A Coupled Hydrologic, Geochemical, And Groundwater Modeling Study, Lilly G. Corenthal

Masters Theses

Focused groundwater discharge in endorheic basins provides opportunities to investigate mechanisms for closing hydrologic budgets in arid regions. The Salar de Atacama (SdA), a closed basin in northern Chile, has accumulated over 1800 km³ of halite and a lithium-rich brine since the late Miocene primarily through evapotranspiration of groundwater. The hydrologic balance of SdA and sources of water and solutes required to explain this deposit are not well constrained. An adapted chloride mass balance method drawing on a database of over 200 water sample sites is applied to a remotely-sensed precipitation dataset to estimate spatially-distributed modern groundwater recharge. Comparing …

Oceanographic Controls On The Expression Of Cretaceous Oceanic Anoxic Events In The Western Interior Sea, Christopher M. Lowery

Doctoral Dissertations

The Cretaceous Period (145-66 Ma) was a time of elevated global temperatures superimposed on fluctuating climate regimes and repeated biotic turnover. It recorded several major perturbations of the carbon cycle, characterized by widespread deposition of organic-rich black shale and benthic and photic zone dysoxia to euxinia, termed oceanic anoxic events (OAEs). The Cenomanian-Turonian OAE2 and the enigmatic Coniacian-Santonian OAE3 are well-preserved in the Western Interior Sea (WIS) of North America. The expression of these OAEs in the WIS differs both from each other and from contemporaneous open-ocean sections. Despite decades of research, questions remain about the role of oceanographic parameters …

Dissolution, Ocean Acidification And Biotic Extinctions Prior To The Cretaceous/Paleogene (K/Pg) Boundary In The Tropical Pacific, Serena Dameron

Masters Theses

The several million years preceding the Cretaceous/Paleogene (K/Pg) boundary has been the focus of many studies. Changes in ocean circulation and sea level, extinctions, and major volcanic events have all been documented for this interval. Important research questions these changes raise include the climate dynamics during the warm, but not hot, time after the decay of the Late Cretaceous greenhouse interval and the stability of ecosystems prior to the mass extinctions at the end-Cretaceous.

I document several biotic perturbations as well as changes in ocean circulation during the Maastrichtian stage of the latest Cretaceous that question whether the biosphere was …

Locating Cryptotephra In Sediments Using Fluid Imaging Technology, Robert D'Anjou, Nicholas L. Balascio, Raymond S. Bradley

Raymond S Bradley

We report a new approach to locate and quantify cryptotephra in sedimentary archives using a continuously-imaging Flow Cytometer and Microscope (FlowCAM_). The FlowCAM rapidly photographs particles flowing in suspension past a microscope lens and performs semi-automated analysis of particle images. It has had primarily biological applications, although the potential sedimentological applications are numerous. Here we test the ability of this instrument to image irregularly shaped, vesicular glass shards and to screen sediment samples for the presence of cryptotephra. First, reference samples of basalt and rhyolite tephra (sieved <63>microns) were analyzed with the FlowCAM, demonstrating the ability of the instrument to …

Holocene Paleo-Environmental Variability Reconstructed From A Lake Sediment Record From Southeast Greenland, Gregory A. De Wet

Masters Theses 1911 - February 2014

Arctic climate variability over the Holocene has been both extensive and, at times, abrupt. Current understanding of these changes is still quite limited with few high-resolution paleoclimate records available for this period. In order to place observed and predicted 21^st century climate change in perspective, reliable and highly resolved paleo-reconstructions of Arctic climate are essential. Using an 8.5 m sediment core from Nanerersarpik Lake, this project will characterize climate changes during the Holocene, including the deglacial transition, the rapid changes that are known to have occurred around 8,200 years ago, the transition from Holocene thermal maximum (HTM) to the …

7700 Years Of Holocene Climatic Variability In Sermilik Valley, Southeast Greenland Inferred From Lake Sediments, Samuel H. Davin

Masters Theses 1911 - February 2014

During the latter half of the 20^th century until present day there has been an unprecedented rise in global annual mean temperatures accompanied by rising sea levels and a decrease in Northern Hemisphere snow cover, which if it continues will lead to widespread disruption of climate patterns, ecosystems, and present-day landscapes. It is therefore of critical importance to establish an expanded network of paleoclimate records across the globe in order to better assesses how the global climate system has changed in the past, that we may create a metric by which to address modern change. Herein is presented a7,700 …

Reading Landscape: Mid-Century Modernism And The Landscape Idea, Jeffrey David Blankenship

Open Access Dissertations

This dissertation traces the recovery of the landscape idea during the middle decades of the 20th century by a group of public intellectuals, scholars and designers responding to the everyday realities of the modern American built environment. That recovery served as a corrective to modernism's construction of landscape as either abstract utopian space or retrogressive historical tableau. The primary catalyst for this renewed interest in landscape as a representation of human cultures and their complex relationship with the natural world was the essayist and critic John Brinckerhoff Jackson (1909-1996) and his magazine Landscape. During the years of Jackson's editorship (1951-1968), …

Lacustrine Records Of Holocene Climate And Environmental Change From The Lofoten Islands, Norway, Nicholas L. Balascio

Open Access Dissertations

Lakes sediments from the Lofoten Islands, Norway, can be used to generate well resolved records of past climate and environmental change. This dissertation presents three lacustrine paleoenvironmental reconstructions that show evidence for Holocene climate changes associated with North Atlantic climate dynamics and relative sea-level variations driven by glacio-isostatic adjustment. This study also uses distal tephra deposits (cryptotephra) from Icelandic volcanic eruptions to improve the chronologies of these reconstructions and explores new approaches to crypto-tephrochronology. Past and present conditions at Vikjordvatnet, Fiskebølvatnet, and Heimerdalsvatnet were studied during four field seasons conducted from 2007-2010. Initially, each lake was characterized by measuring water …

Final Evaluation Report, Sagefox Consulting Group

IPY STEM Polar Connections

No abstract provided.

Melting Ice And Sea Level Changes, Morton Sternheim

IPY STEM Polar Connections

A simple experiment to demonstrate the effects of melting sea.

Thermohaline Circulation, Rob Snyder

IPY STEM Polar Connections

Surface currents, such as the Gulf Stream, are pushed by the wind. Deep ocean currents, called the “Thermohaline Circulation”, are the result of changes in the density of water. In this activity you can investigate how differences in the temperature and salinity of water can produce deep ocean currents

Globe Walk, Rob Snyder

IPY STEM Polar Connections

A “Globe Walk” can be used as a demonstration or classroom activity to guide students toward a better understanding of the affects that Earth’s axial tilt, rotation on Earth’s axis, and orbital motion have on the angles of incidence of sunlight, the lengths of daytimes, and solar insolation.

Polar Remote Sensing, Beth Caissie

IPY STEM Polar Connections

•Satellite sensors specialize in collecting data about specific wavelengths The Geostationary Operational Environment Satellites (GOES) operated by NASA, NOAA, and the U.S. Department of Commerce provide continuous monitoring of weather conditions. Orbiting the Earth’s equatorial plane at a speed exactly matching the planet’s rotation, satellites in the GOES network seem to hover over fixed spots. They monitor atmospheric conditions that lead to hurricanes, flash floods, tornadoes, and hail storms.

Detecting Atmospheric Carbon Dioxide With Btb, Stephan Schneider

IPY STEM Polar Connections

A study of the concentration of carbon dioxide gas in air samples requires an understanding of effective sampling techniques, the use of pH indicators, an understanding of chemical reactions that result on the formation of acidic compounds, and an understanding of the chemical processes that contribute to the composition and characteristics of Earth’s atmosphere.

Global Warming And Arctic Climate, Ray Bradley

IPY STEM Polar Connections

No abstract provided.

Build A Remote Sensing Satellite, Rob Snyder

IPY STEM Polar Connections

•Build a model of a remote sensing satellite. •Use your model of a satellite to transform reflected visible of different frequencies into electrical signals with different voltages. •Use different colors of paper to calibrate the model. •Create a model of a landscape using three different colors of paper. •Create a “false color” image of the model of a landscape (if time permits).

Seasonal Changes In Sea Ice, Rob Snyder

IPY STEM Polar Connections

No abstract provided.

Why The Arctic? An Overview, Julie Brigham-Grette

IPY STEM Polar Connections

No abstract provided.