Earth Sciences Commons^™

Trace-Element And Physical Response To Melt Percolation In Summit (Greenland) Snow, Gifford J. Wong, Robert L. Hawley, Eric R. Lutz, Erich C. Osterberg

Dartmouth Scholarship

Surface melt on a glacier can perturb the glaciochemical record beyond the natural variability. While the centre of the Greenland ice sheet is usually devoid of surface melt, many high- Arctic and alpine ice cores document frequent summertime melt events. Current hypotheses interpreting melt-affected ice-core chemistry rely on preferential elution of certain major ions. However, the precise nature of chemistry alteration is unknown because it is difficult to distinguish natural variability from melt effects in a perennially melt-affected site. We use eight trace-element snow chemistry records recovered from Summit, Greenland, to study spatial variability and melt effects on insoluble trace …

A Study Of The Impacts Of Freeze-Thaw On Cliff Recession At The Calvert Cliffs In Calvert County, Maryland, Bonnie Elizabeth Zwissler

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

The Calvert Cliffs, which form much of the western coastline of the Chesapeake Bay in Calvert County, Maryland, are actively eroding and destabilizing, resulting in a critical situation for many homes in close proximity to the slope's crest. Past studies have identified that where waves directly interact with the toe of the slope, wave action controls cliff recession; however, where waves do not regularly interact with the slope toe, the past work identified that freeze-thaw controls recession. This study investigated the validity of this second claim by analyzing the recession rate and freeze-thaw behavior of six study sites along the …

Trophic State Monitoring Of Lakes And Reservoirs Using Remote Sensing, Michelle Aten

Electronic Theses and Dissertations

Lakes and reservoirs are important resources that provide water for critical needs, such as drinking water, agriculture, recreation, fisheries, wildlife, and other uses. However, there is increasing concern that anthropogenic eutrophication threatens the usability of these natural resources. Therefore, this research investigates these complex hydrologic ecosystems and recommends a methodology for monitoring the trophic state of lakes and reservoirs using remote sensing data. The Mississippi Department of Environmental Quality provided in situ data for seven Mississippi lakes including, Arkabutla, Bay Springs, Enid, Grenada, Okatibbee, Ross Barnett, and Sardis lakes. This research explored the relationships between the Secchi depth (SD), chlorophyll-a …

Effects Of Stress And Water Saturation On Seismic Velocity And Attenuation In Near Surface Sediments, James Michael Crane

LSU Doctoral Dissertations

Seismic investigation in the near-surface is complicated by highly attenuating media, large interparticle stresses, and variable water saturation, so new tools and methodology are necessary to understand the relationships between velocity, attenuation, and physical properties of the propagating media. A new shear wave source is developed for investigation of gas-charged, organic-rich sediments because compressional waves are highly attenuated and currently available sources are inadequate. The new source compares favorably to a traditional hammer impact source, producing a signal with a broader-band of frequencies (30-100Hz cf. 30-60Hz) and signal-to-noise ratios (SNR) equivalent to ~3 stacked hammer blows to the hammer impact …

Analysis Of The Cyclostratigraphy At The Devonian-Carboniferous Boundary In South-Central Oklahoma, Ryan Michael Todd Ellis

LSU Master's Theses

An outcrop in La Serre, France, was officially ratified by the ICS in 1989, and the IUGS in 1990, as the location of the Global Boundary Stratotype Section and Point (GSSP) for the Famennian–Tournaisian, and subsequently the Devonian–Carboniferous (D–C) boundary. GSSPs, like this one, are official outcrops that provide physical representations of geologic time boundaries, essentially geological standards that define geologic time, providing a vital framework to model a variety of interpretations of geological phenomena from paleoclimate to paleontological. It has been acknowledged that the GSSP in La Serre, France is in need of revision due to fossil reworking and …

Using Existing Programs As Vehicles To Disseminate Knowledge, Provide Opportunities For Scientists To Assist Educators, And To Engage Students In Using Real Data., Steven Smith, Kristin Wegner, Benjamin D. Branch, Bridget Miller, Darrell G. Schulze, Ann M. Bessenbacher

Libraries Faculty and Staff Presentations

Many national and statewide programs throughout the K-12 science education environment teach students about science in a hands-on format, including programs such as Global Learning and Observations to Benefit the Environment (GLOBE), Project Learning Tree (PLT), Project Wild, Project Wet, and Hoosier River Watch. Partnering with one or more of these well-known programs can provide many benefits to both the scientists involved in disseminating research and the K-12 educators. Scientists potentially benefit by broader dissemination of their research by providing content enrichment for educators. Educators benefit by gaining understanding in content, becoming more confident in teaching the concept, and increasing …

Assessing Continuous Contamination Discharge From A Combined Sewer Outfall (Cso) Into A Tidal Wetland Creek: Bacteriological And Heavy Metals Indicators, Timothy Eaton, Gregory D. O'Mullan, Ashaki A. Rouff

Publications and Research

Continuous discharge from a combined sewer overflow (CSO) into a tidal wetland creek in the New York City urban area was analyzed to assess the extent of water quality degradation from fecal bacteria contamination during both dry and wet weather. A combination of fecal indicator bacteria (FIB), total suspended solids, and dissolved metals were used to infer the presence of sewage pollution from the CSO discharge and to constrain the spatial and temporal impact on water quality and dry season creek flows. Upstream of the CSO, creek flow was dominated by groundwater input, and FIB levels were very low or …

Providing Educators Authentic Scientific Research Opportunities Through Integration Of Research Content And Technology With Globe Teacher Workshops Using An Integrated Model Of Professional Development, Steven Smith, Kristin Wegner, Benjamin D. Branch, Bridget Miller, Darrell G. Schulze, Ann M. Bessenbacher

Libraries Faculty and Staff Presentations

No abstract provided.

A Library Approach To Establish An Educational Data Curation Framework (Edcf) That Supports K-12 Data Science Sustainability, Benjamin D. Branch, Kristin Wegner, Steven Smith, Darrell G. Schulze, Venkatesh Merwade, Jinha Jung

Libraries Faculty and Staff Presentations

It has been the tradition of the libraries to support literacy. Executive Order, Making Open and Machine Readable the New Default for Government Information, May 9, 2013, implies new roles for libraries. The library has the responsibility to support geospatial data, big data, earth science data or cyber infrastructure data that may support STEM for educational pipeline stimulation. (More information can be found at http://www.whitehouse.gov/the-press-office/2013/05/09/executive-order-making-open-and-machine-readable-new-default-government-.)

Provided is an Educational Data Curation Framework (EDCF) that has been initiated in Purdue research. The EDCF may be applied to geospatial data service, engagement and outreach endeavors to augment the data science and climate …

Applications Of Satellite Remote Sensing In Archeology, Kel Markert

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Copper And Nickel Partitioning With Nanoscale Goethite, Kelsey Marie Danner

Browse all Theses and Dissertations

Goethite is an ideal sorbent for investigations of metal partitioning with iron oxyhydroxides because it is the most abundant iron oxyhydroxide in sediments (Langmuir, 1997; van der Zee et al., 2003), and cations have a strong affinity for goethite (Coughlin and Stone, 1995). Steady-state partitioning of nickel (Ni) and copper (Cu) to nanoscale goethite (a-FeOOH) was investigated experimentally under conditions intended to be representative of those in natural waters. Manipulated conditions included i) sorbent mass, ii) solute metal concentration, iii) reaction time, iv) pH, v) ionic strength (I), and vi) humate concentration (competitive ligand) to examine how these factors influenced …

Trace Metals In Sediments On The Continental Margin Of The Northwest Atlantic Ocean, Daniel L. Marsh

Browse all Theses and Dissertations

Trace metals in the ocean are derived from natural and anthropogenic sources. Despite increased human impact on the marine environment and biological productivity of continental margins, trace metal studies in marine sediments have focused primarily on near-shore regions. I investigated 22 metals in sediments on the continental margin of the northwest Atlantic Ocean to calculate enrichment factors (EF) relative to upper continental crust and identify spatial variations with distance from shore and depth below the sediment-seawater interface. Metals were well correlated with Al, Fe, organic matter, or CaCO3. No clear trends in metal EFs with distance from shore were evident …

Enhanced Resolution Of The Paleoenvironmental And Diagenetic Features Of The Silurian Brassfield Formation, Lisa Marie Oakley

Browse all Theses and Dissertations

The Brassfield Formation is an early Silurian (Aeronian, Llandoverian) unit of limestone and dolostone with excellent preservation of early reef communities and a diverse invertebrate fauna. A well-preserved outcrop occurs in southwestern Ohio at the Oakes Quarry Park in Fairborn; it contains abundant corals and stromatoporoids that are co-dominant in reef and reef-affected settings. This research provided an enhanced perspective of the Brassfield Formation to better reconstruct its paleoenvironment and better understand its diagenetic features. The depositional and diagenetic features of the Brassfield are described and interpreted using histologic methods and light microscopy. Selected thin sections were treated with carbonate …

Quantitative Analysis Of The Polarity Reversal Pattern Of The Earth's Magnetic Field And Self-Reversing Dynamo Models, Patrick Shane Craig

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The geologic record documents that the Earth's magnetic field has reversed 284 times over the past 160 Myr. This study uses two methods to analyze the scaling properties of the pattern of geomagnetic reversals and to analyze the scaling properties of reversals output by two mathematical self-reversing dynamo models, the Rikitake (1958) two-disk dynamo and the magnetohydrodynamic (MHD) model of Driscoll and Olson (2011). The first analysis method plots the duration versus cumulative probability for geomagnetic polarity intervals ranging between 0.01 and 35 Myr. The Kolmogorov-Smirnov statistic is used to determine the optimal minimum value of xmin at which power …

Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif

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A stromatolite is a laminated benthic microbial deposit. Its uniqueness arises from being present since the Precambrian to the present. Stromatolites recorded a peak time during the Mesoproterozoic, subsequently they witnessed abrupt rises and falls in abundance with the steepest decline in the Ordovician period, from which it never recovered from. There is no consensus yet regarding the reasons behind the decline of stromatolites. Thus the decline of these microbial deposits remains an enigma. Additionally, a literature gap exists regarding the reasons that specifically led to the Ordovician decline. Accordingly, the focus of this literature-based MSc. thesis is to find …

Abiotic Degradation Of Chlorinated Hydrocarbons (Chcs) With Zero-Valent Magnesium (Zvm) And Zero-Valent Palladium/Magnesium Bimetallic (Pd/Mg)-Reductant, Fang Yu

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Chlorinated hydrocarbons (CHCs) in groundwater can be treated by monometallic and bimetallic metal reductants through abiotic degradation. The breakdown of CHC is achieved by gaining electrons from those reductants and removing chlorines from CHC molecules to transform the CHCs into less chlorinated compounds. As a proven technology in groundwater treatment, permeable reactive barriers (PRBs) have been used to passively treat contaminated groundwater, in which granular metals can be used as reactive materials. This study explored the abiotic degradation of CHCs by zero-valent magnesium (ZVM) and bimetallic palladium/magnesium (Pd/Mg) reductants. Different CHCs (carbon tetrachloride, chloroform, dichloromethane (DCM), 1,2-dichloroethane (1,2-DCA), 1,1,2-trichloroethane (1,1,2-TCA), …

Front Cover

International Journal of Speleology

No abstract provided.

Appropriate Terminology For Karst-Like Phenomena: The Problem With ‘Pseudokarst’, Rolan S. Eberhard, Chris Sharples

International Journal of Speleology

The practice of referring to certain morphologically karst-like phenomena as ‘pseudokarst’ is problematic, because it ignores basic principles of sound classification, logical naming conventions and accepted geomorphic classifications and terminology. These problems have compounded the difficulty in establishing an accepted classification of ‘pseudokarst’ types. The practice embodies a karst-centric perspective which should be avoided in favour of using conventional geomorphic terminology for non-karstic features. We illustrate this by providing existing conventional terms for many ‘pseudokarst’ types reported in the literature.

Book Review: Speleothem Science: From Process To Past Environments, Giovanni Zanchetta

International Journal of Speleology

Ian J. Fairchild and Andy Baker.
Speleothem Science: From Process to Past Environments
Wiley Blackwell, 2012. Hardcover, 450 p.,
ISBN-10: 1405196203, ISBN-13: 978-1405196208, €57

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …

The Effects Of Mean Sea Level And Tidal Amplitude On Ground Water Discharge And Pore-Water Salinity Distribution Along A Forest/Marsh Boundary, North Inlet, Sc, John Bradley Peurifoy

Theses and Dissertations

Advective groundwater flow in salt marshes is an important mechanism through which nutrients are exported to adjacent coastal waters. Groundwater flow also influences the distribution of pore-water salinity in the subsurface marsh, which affects botanical zonation, nutrient transport, and primary productivity. Recent idealized marsh island simulations have suggested that increases in tidal amplitude result in increased groundwater discharge, and that the elevation of MWL relative to the marsh platform is inversely related to groundwater discharge. These simulations were only representative of marsh islands (as opposed to forest-marsh boundaries) and relied on simulated tides and MWL position. The results were not …

Post-Emplacement Leaching Behaviors Of Nano Zero Valent Iron Modified With Carboxymethylcellulose Under Simulated Aquifer Conditions, Leslie Lavinia Williams

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Nanoscale particles of zero valent iron stabilized with carboxymethylcellulose (CMC-nZVI) have been shown to degrade chlorinated hydrocarbons efficiently in bench-scale investigations. The remediation of contaminated sites by subsurface injection of stabilized nZVI in a slurry form has been investigated at pilot scale and field scale with conflicting results concerning transport of stabilized nZVI and its long-term stability for in situ degradation of chlorinated hydrocarbons. Changes in the hydraulic conductivity in porous media have also been reported following injection of stabilized nZVI slurry in both large tank experiments and in field studies. This study investigated the leaching behavior of CMC-nZVI post-emplacement …

Saturated Thickness Of The Unconfined Portions Of The High Plains Aquifer, Conservation And Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

The Groundwater Atlas Of Nebraska, Jesse T. Korus, Leslie M. Howard, Aaron R. Young, Dana P. Divine, Mark E. Burbach, J. Michael Jess, Douglas R. Hallum, R.F. Diffendal, Jr., R.M. Joeckel

Conservation and Survey Division: Faculty and Staff Publications

Groundwater has long been important to inhabitants of Nebraska. Native Americans in the Great Plains erected their villages near water sources. Early explorers from Europe and pioneers heading west following river valleys depended on ample freshwater in the Nebraska Territory for drinking water and livestock supplies. These Europeans, however, considered the Nebraska Territory part of “The Great American Desert” and few people had an idea of the vast groundwater resource in Nebraska.

Prelude To Seven Slots: Filling And Subsequent Modification Of Seven Broad Canyons In The Navajo Sandstone, South-Central Utah, David B. Loope, Ronald J. Goble, Joel P. L. Johnson

Department of Earth and Atmospheric Sciences: Faculty Publications

Within a four square kilometer portion of Grand Staircase-Escalante National Monument, seven distinct slot canyons cut the Jurassic Navajo Sandstone. Four of the slots developed along separate reaches of a trunk stream (Dry Fork of Coyote Gulch), and three (including canyons locally known as “Peekaboo” and “Spooky”) are at the distal ends of south-flowing tributary drainages. All these slot canyons are examples of epigenetic gorges—bedrock channel reaches shifted laterally from previous reach locations. The previous channels became filled with alluvium, allowing active channels to shift laterally in places and to subsequently re-incise through bedrock elsewhere. New evidence, based on optically …

Nebraska Statewide Groundwater-Level Monitoring Report 2013, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly

United States Geological Survey: Staff Publications

Although numerous studies have attempted to place species of interest within the context of food webs, such efforts have generally occurred at small scales or disregard potentially important spatial heterogeneity. If food web approaches are to be employed to manage species, studies are needed that evaluate the multiple habitats and associated webs of interactions in which these species participate. Here, we quantify the food webs that sustain rearing salmon and steelhead within a floodplain landscape of the Methow River, Washington, USA, a location where restoration has been proposed to restore side channels in an attempt to recover anadromous fishes. We …

Predictive Models For Escherichia Coli Concentrations At Inland Lake Beaches And Relationship Of Model Variables To Pathogen Detection, Donna S. Francy, Erin A. Stelzer, Joseph W. Duris, Amie M. G. Brady, John H. Harrison, Heather E. Johnson, Michael W. Ware

United States Geological Survey: Staff Publications

Predictive models, based on environmental and water quality variables, have been used to improve the timeliness and accuracy of recreational water quality assessments, but their effectiveness has not been studied in inland waters. Sampling at eight inland recreational lakes in Ohio was done in order to investigate using predictive models for Escherichia coli and to understand the links between E. coli concentrations, predictive variables, and pathogens. Based upon results from 21 beach sites, models were developed for 13 sites, and the most predictive variables were rainfall, wind direction and speed, turbidity, and water temperature. Models were not developed at sites …

The Malthusian–Darwinian Dynamic And The Trajectory Of Civilization, Jeffrey C. Nekola, Craig D. Allen, James H. Brown, Joseph R. Burger, Ana D. Davidson, Trevor S. Fristoe, Marcus J. Hamilton, Sean T. Hammond, Astrid Kodric-Brown, Norman Mercado-Silva, Jordan G. Okie

United States Geological Survey: Staff Publications

Two interacting forces influence all populations: the Malthusian dynamic of exponential growth until resource limits are reached, and the Darwinian dynamic of innovation and adaptation to circumvent these limits through biological and/or cultural evolution. The specific manifestations of these forces in modern human society provide an important context for determining how humans can establish a sustainable relationship with the finite Earth.

A Causal Examination Of The Effects Of Confounding Factors On Multimetric Indices, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Brian R. Mitchell, Glenn R. Guntenspergen

United States Geological Survey: Staff Publications

The development of multimetric indices (MMIs) as a means of providing integrative measures of ecosystem condition is becoming widespread. An increasingly recognized problem for the interpretability of MMIs is controlling for the potentially confounding influences of environmental covariates. Most common approaches to handling covariates are based on simple notions of statistical control, leaving the causal implications of covariates and their adjustment unstated. In this paper, we use graphical models to examine some of the potential impacts of environmental covariates on the observed signals between human disturbance and potential response metrics. Using simulations based on various causal networks, we show how …