Geology Commons^™

A Global Standard For Monitoring Coastal Wetland Vulnerability To Accelerated Sea-Level Rise, Edward L. Webb, Daniel A. Friess, Ken W. Krauss, Donald R. Cahoon, Glenn R. Guntenspergen, Jacob Phelps

United States Geological Survey: Staff Publications

Sea-level rise threatens coastal salt-marshes and mangrove forests around the world, and a key determinant of coastal wetland vulnerability is whether its surface elevation can keep pace with rising sea level. Globally, a large data gap exists because wetland surface and shallow subsurface processes remain unaccounted for by traditional vulnerability assessments using tide gauges. Moreover, those processes vary substantially across wetlands, so modelling platforms require relevant local data. The low-cost, simple, high-precision rod surface-elevation table–marker horizon (RSET-MH) method fills this critical data gap, can be paired with spatial data sets and modelling and is financially and technically accessible to every …

Use Of Nmr Logging To Obtain Estimates Of Hydraulic Conductivity In The High Plains Aquifer, Nebraska, Usa, Katherine Dlubac, Rosemary Knight, Yi-Qiao Song, Nate Bachman, Ben Grau, Jim Cannia, John Williams

United States Geological Survey: Staff Publications

Hydraulic conductivity (K) is one of the most important parameters of interest in groundwater applications because it quantifies the ease with which water can flow through an aquifer material. Hydraulic conductivity is typically measured by conducting aquifer tests or wellbore flow (WBF) logging. Of interest in our research is the use of proton nuclear magnetic resonance (NMR) logging to obtain information about water-filled porosity and pore space geometry, the combination of which can be used to estimate K. In this study, we acquired a suite of advanced geophysical logs, aquifer tests, WBF logs, and sidewall cores at the …

Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle

United States Geological Survey: Staff Publications

Recently developed spatial capture-recapture (SCR) models represent a major advance over traditional capture-recapture (CR) models because they yield explicit estimates of animal density instead of population size within an unknown area. Furthermore, unlike non-spatial CR methods, SCR models account for heterogeneity in capture probability arising from the juxtaposition of animal activity centers and sample locations. Although the utility of SCR methods is gaining recognition, the requirement that all individuals can be uniquely identified excludes their use in many contexts. In this paper, we develop models for situations in which individual recognition is not possible, thereby allowing SCR concepts to be …

The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs

United States Geological Survey: Staff Publications

Study of geologic records of dust composition, sources and deposition rates is important for understanding the role of dust in the overall planetary radiation balance, fertilization of organisms in the world’s oceans, nutrient additions to the terrestrial biosphere and soils, and for paleoclimatic reconstructions. Both glacial and non-glacial processes produce fine-grained particles that can be transported by the wind. Geologic records of dust flux occur in a number of depositional archives for sediments: (1) loess deposits; (2) lake sediments; (3) soils; (4) deep-ocean basins; and (5) ice sheets and smaller glaciers. These archives have several characteristics that make them highly …

Abiotic Nitrate And Nitrite Reactivity With Iron Oxide Minerals, Prakash Dhakal

Theses and Dissertations--Plant and Soil Sciences

Under iron (Fe³⁺)-reducing conditions where aqueous Fe²⁺ and unreduced solid Fe³⁺-oxides commonly coexist, soil Fe²⁺ oxidation has been shown to be coupled with nitrate (NO₃^-) reduction. One possible secondary reaction is the involvement of NO₃^- and nitrite (NO₂^-) with Fe-oxide minerals found in many natural environments. Yet, spectroscopic measurements and kinetic data on reactivity of NO₃^- and NO₂^- with Fe-containing oxide minerals such as goethite (a-FeOOH), and magnetite (Fe₃O­₄) are not found in the literature. The reactivity of …

Lithological And Sequence Stratigraphic Examination Of The Madison Group Marker Beds, Eastern Williston Basin Margin, North Dakota, Troy Jd. Skitt

Theses and Dissertations

The Frobisher-Alida interval consists of eight log-defined subintervals or “beds” within the Mississippian upper Mission Canyon and lower Charles Formations of the Madison Group in the Williston Basin. The subintervals are composed of predominantly evaporite and carbonate lithologies, and include in descending order: 1) Midale, 2) Rival, 3) Bluell, 4) Sherwood, 5) Mohall, 6) Glenburn, 7) Wayne, and 8) Landa. The top of the lower six subintervals are separated by thin but areal extensive log-defined markers of contrasting lithologies and include in descending order: 1) State A, 2) Sherwood Argillaceous Marker (S.A.M.), 3) K-1, 4) K-2, 5) K-3, and 6) …

A Comparison Of Pixel-Based Versus Object Oriented Analysis Of Landslides Using Historical Remote Sensing Data, Ren N. Keyport

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

With recent advances in remote sensing processing technology, it has become more feasible to begin analysis of the enormous historic archive of remotely sensed data. This historical data provides valuable information on a wide variety of topics which can influence the lives of millions of people if processed correctly and in a timely manner. One such field of benefit is that of landslide mapping and inventory. This data provides a historical reference to those who live near high risk areas so future disasters may be avoided. In order to properly map landslides remotely, an optimum method must first be determined. …

Geol 440/840: Tectonics—A Peer Review Of Teaching Project Inquiry Portfolio, Caroline M. Burberry

UNL Faculty Course Portfolios

This document is a follow-up document to the Benchmark Portfolio for this course, created in 2012. It details the changes made to the course following the observations from the Benchmark Portfolio and demonstrates that discussion of the metacognitive issues surrounding critical thinking does have some effect on increasing student learning. The document concludes with changes which will be made to the 2014 iteration of the class, to continue this inquiry and improvement process.

Geol 106: Environmental Geology—A Peer Review Of Teaching Project Benchmark Portfolio, Leilani Arthurs

UNL Faculty Course Portfolios

The Peer Review of Teaching (PRT) program provides faculty members the environment, support, structure, and time to carefully think about how they teach a particular course. PRT benchmark portfolios are prepared as a part of this program to assist faculty members in reflecting on and documenting their instructional practices and the potential impact they have on student learning.

This benchmark portfolio targets the Spring 2013 semester of GEOL 106: Environmental Geology. It documents the course objectives that provided the foundation for the instructional approach, the course-level learning goals that defined what students should be able to do by the end …

Sediment Impact On The Formation Of Hypoxic Waters In The Northern Gulf Of Mexico: A Synthesis Of Sediment Texture, Composition, Erodibility And Transport, Rangley Claude Mickey

Electronic Theses and Dissertations

Annual hypoxic events have been found to occur over the past several decades in the northern Gulf of Mexico (nGOM) and have prompted researchers to begin studying the mechanisms that control hypoxia formation so they may advise policy makers on the appropriate mitigating responses. This has led to the development of 3-dimensional modeling systems that incorporate marine physical, biological, geological, and chemical processes that may impact the formation and duration of hypoxic regimes in the nGOM. This study used field, laboratory, and modeling techniques to examine how sediment may be eroded from the seabed and where/how it is transported across …

Are 34s-Enriched Authigenic Sulfide Minerals A Proxy For Elevated Methane Flux And Gas Hydrates In The Geologic Record?, Walter S. Borowski, Nancy M. Rodriguez, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

The sulfate–methane transition (SMT) zone is a diagenetic transition within anoxic marine sediments created by the metabolic activity of a consortium of sulfate-reducing bacteria and methane-oxidizing Archaea. As interstitial dissolved sulfate is consumed by microbially mediated sulfate reduction of sedimentary organic matter (SOM) and anaerobic oxidation of methane (AOM) large enrichments of ³⁴S occur in the interstitial sulfate pool. These isotopic enrichments are transmitted to the dissolved sulfide pool (∑HS⁻) and subsequently into sulfide minerals (So, ∼FeS, FeS₂).

We investigate the sulfur isotopic composition of pore-water sulfate and sulfide minerals at three sites underlain …

Subsurface Imaging And Petrophysical Analysis Of The South Georgia Rift Basin, South Carolina, Olusoga Martins Akintunde

Theses and Dissertations

The Triassic-Jurassic South Georgia Rift (SGR) basin, buried beneath Coastal Plain sediments of southern South Carolina, southeastern Georgia, western Florida, and southern Alabama, consists of an assemblage of continental rift deposits (popularly called red beds), and mafic igneous rocks (basalt flows and diabase sills). The red beds are capped by basalts and/or diabase sills, and constitute the target for supercritical CO2 storage as part of a Department of Energy funded project to study feasibility for safe and long-term sequestration. This study addresses key stratigraphic, structural and petrophysical issues critical to determine subsurface suitability for CO2 storage as well as improved …

Benthic Boundary Layer Processes: Bedform Evolution And Bottom Turbulence, Timothy Robert Nelson

Theses and Dissertations

Bedform roughness, caused by ripples on the seabed, plays an important role in controlling sediment dynamics in the nearshore region. In this dissertation, the temporal and spatial evolution of ripples from two field sites located in the South Atlantic Bight, offshore Long Bay, SC and Georgia are used to relate wave-induced ripple geometry (wavelength and orientation) to near bed directional wave velocities. 2-D spectral analysis techniques were developed to automate detection of ripple wavelength, direction, and irregularity. This analysis showed that magnitude, direction, and duration of wave forcing controls ripple geometry and irregularity. During highly energetic events, ripple geometry changes …

Morphological Changes Associated With Tropical Storm Debby In The Vicinity Of Two Tidal Inlets, John's Pass And Blind Pass, West-Central Florida, Andrew Brownell

USF Tampa Graduate Theses and Dissertations

Tropical Storm Debby affected the Gulf coast of Florida in late June, 2012. The storm's southerly approach temporarily reversed the annual net southward longshore sediment transport. The energetic conditions associated with Tropical Storm Debby can be seen in the wind, wave and tidal measurements taken from both onshore and offshore weather stations around the dual tidal inlets system of John's Pass and Blind Pass, approximately 25 kilometers north of the mouth of Tampa Bay. The energetic and persistent southerly forcing, in addition to higher storm induced water levels and wave heights, resulted in atypical beach erosion and sediment deposition on …

Deciphering Deposits: Using Ground Penetrating Radar And Numerical Modeling To Characterize The Emplacement Mechanisms And Associated Energetics Of Scoria Cone Eruption And Construction, Leah Michelle Courtland

USF Tampa Graduate Theses and Dissertations

Our understanding of tephra depositional processes is significantly improved by high-resolution ground-penetrating radar (GPR) data collected at Cerro Negro volcano, Nicaragua. The data reveal three depositional regimes: (1) a near-vent region on the cone itself, where 10 GPR radargrams collected on the western flank show quantifiable differences between facies formed from low energy normal Strombolian and higher energy violent Strombolian processes, indicating imaging of scoria cone deposits may be useful in distinguishing eruptive style in older cones where the proximal to distal tephra blanket has eroded away; (2) a proximal zone in which horizons identified in crosswind profiles collected at …

Optimized Correlation Of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida, Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

Abstract

Sinkholes and sinkhole-related features in West-Central Florida (WCF) are commonly identified using geotechnical investigations such as standard penetration test (SPT) borings and geophysical methods such as ground penetrating radar (GPR) and electrical resistivity tomography (ERT). Geophysical investigation results can be used to locate drilling and field testing sites while geotechnical investigation can be used to ground truth geophysical results. Both methods can yield complementary information. Geotechnical investigations give important information about the type of soil, groundwater level and presence of low-density soils or voids at the test location, while geophysical investigations like GPR surveys have better spatial coverage and …

Short And Long Term Volcano Instability Studies At Concepción Volcano, Nicaragua, Jose Armando Saballos

USF Tampa Graduate Theses and Dissertations

Concepción is the most active composite volcano in Nicaragua, and is located on Ometepe Island, within Lake Nicaragua. Moderate to small volcanic explosions with a volcanic explosivity index (VEI) of 1-2 have been characteristic of this volcano during the last four decades. Although its current activity is not violent, its volcanic deposits reveal stages of violent activity involving Plinian and sub-Plinian eruptions that deposited vast amounts of volcanic tephra in the Atlantic Ocean. These observations, together with the 31,000 people living on the island, make Concepción volcano an important target for volcanological research.

My research focuses on the investigation of …

Distinguishing Processes That Induce Temporal Beach Profile Changes Using Principal Component Analysis: A Case Study At Long Key, West-Central Florida, Denise Marie Davis

USF Tampa Graduate Theses and Dissertations

The heavily developed Long Key is located in Pinellas County in west-central Florida. The structured Blind Pass at the north end of the barrier island interrupts the southward longshore sediment transport, resulting in severe and chronic beach erosion along the northern portion of the island. Frequent beach nourishments were conducted to mitigate the erosion. In this study, the performance of the most recent beach nourishment in 2010 is quantified through time-series beach profile surveys. Over the 34-month period, the nourished northern portion of the island, Upham Beach, lost up to 330 m3/m of sand, with a landward shoreline retreat of …

Ecology Of The Late Neogene Extinctions: Perspectives From The Plio-Pleistocene Of Florida, Shubhabrata Paul

USF Tampa Graduate Theses and Dissertations

The ecological impact of past extinction events is one of the central issues in paleobiology. In face of present environmental changes, a better understanding of past extinctions will enable us to identify the magnitude of biodiversity crises and their underlying processes. The Late Neogene was a time of extraordinary climatic reorganization, including Northern Hemisphere glaciation, the rise of the Central American Isthmus, and associated changes in environmental conditions. Therefore, the Late Neogene extinctions of marine molluscs of South Florida present an ideal platform to examine the interaction between environmental changes and biotic response. In the present study, three different aspects …

Hypogene Speleogenesis In The Cerna River Basin, Sw Romania: A Sedimentological, Mineralogical, And Stable Isotopic Approach, Cristina Montana Puscas

USF Tampa Graduate Theses and Dissertations

Ever since it was identified as a speleogenetic process in the Guadalupe Mountains of New Mexico, USA, hypogene speleogenesis has become the focus of numerous research projects aimed at discerning between classical epigene caves and sulfuric acid or thermal caves. The first distinguishing characteristics that were recognized for hypogene caves were passage and cave morphology. The following step was the identification of rare minerals, specific for processes associated to hypogene speleogenesis. One other important step was the recognition of the importance of stable isotopes - mainly of S - in tracing the source of S and the chemical processes affecting …

The Extent Of Phosporus Redox Chemistry In West Central Florida Waters, Jacqueline Marie Sampson

USF Tampa Graduate Theses and Dissertations

Phosphorus (P) has long been acknowledged as a vital nutrient for living organisms and is a key factor responsible for the fresh water eutrophication. Our understanding of the phosphorus cycle has been limited by: (1) the common assumption that all P in the environment occurs primarily as phosphates and (2) by the limited analytical methods available to identify P speciation. In an attempt to understand the distribution and chemistry of phosphorus within a freshwater system we must be able to identify individual P species. To this end, we used a coupled High Performance Liquid Chromatograph (HPLC) - Inductively Coupled Plasma …

Stable Isotopes And Trace Elements In Tooth Enamel Bioapatite: Effects Of Diagenesis And Pretreatment On Primary Paleoecological Information, Jessica Norman Wilson

USF Tampa Graduate Theses and Dissertations

The geochemical analysis of bioapatite in vertebrate skeletal tissues is an important tool used to obtain ecological information from fossil animals. An important consideration when conducting stable isotope and trace element analyses is obtaining biogenic information that has been unaffected by diagenetic processes.

A two-step pretreatment procedure is commonly used remove diagenetically altered material by removing organic material, via an oxidation reaction with H2O2 or NaOCl, and secondary carbonate, via dissolution in dilute acetic acid, from bioapatite. While much work has been done to determine the efficacy of the pretreatment process, little research has been conducted to determine the potential …

Tidal Flux Of Trace Metals And Rare Earth Elements In A Barrier Island Salt Marsh, Ryan Antle

Theses and Dissertations

Barrier island salt marshes are known as sources of nutrients to the coastal ocean but it is unclear whether they are also sources or sinks of trace metals in regards to coastal waters. Salt marshes are characterized by steep redox and biogeochemical gradients, which constantly fluctuate as a result of tidal pumping. While several studies have examined metal budgets between terrestrial fresh water, estuarine subterranean fluids, and coastal saline waters, there is little data regarding fluid chemistry for metals in salt water estuaries in the absence of fresh water input. This study investigated a back barrier salt marsh on Cabretta …

Tectonics Of The South Georgia Rift, David Michael Heffner

Theses and Dissertations

Triassic rifting of the supercontinent Pangea left behind numerous basins on what is now the eastern North American margin. The South Georgia Rift (SGR) was thought to be the best preserved of these basins having been capped by thick basalt flows of the Central Atlantic Magmatic Province (CAMP) and later buried beneath the Cretaceous and younger Coastal Plain. Because it is buried beneath the Coastal Plain, the SGR is only known through sparse drilling and geophysical methods. Despite this limited dataset, the SGR is the only one of the eastern North American Triassic basins known to overlie the ancient Alleghanian …

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

Geochemical And Isotopic Characterization Of Lead In Fugitive Dust From Unsurfaced Roads In Missouri, Emitt C. Witt

Doctoral Dissertations

"Eighteen unsurfaced roadways in Missouri's rural Ozark region were sampled to characterize the differences in trace element and isotopic chemistry to determine if there is a human health concern with inhaling and/or ingestion of fugitive dust generated by a moving vehicle. Road reaches were selected to represent those in similar rural areas with and without the presence of mining activity--13 roads were selected in the Viburnum Trend (VT) resource mining area and five were located to the southwest of the mining areas. Samples were collected using a novel cyclonic fugitive dust sampler (patent pending) that collects a composite sample from …

Palynology Of Acid-Saline Lakes Of Western Australiabiostratigraphy And Paleoenvironmental Reconstruction, Carlos A. Sanchez Botero

Doctoral Dissertations

"Lakes are excellent repositories of fossils and sedimentary features that provide clues to past climatic and geologic events. Sediments from four cores drilled in Lake Aerodrome (LA1-09, LA2-09) and Lake Brown (LB1-09, LB2-09), two of the hundreds of ephemeral lakes in southern Western Australia, were analyzed for their palynological contents to understand the geologic and climatic evolution of the depositional basin. Palynofacies assemblages defined by statistical analyses of dispersed organic matter suggested differences in the depositional conditions and probable correlations between Lake Aerodrome cores. Detailed identifications and quantification of organic-walled microfossils yielded two palynomorph assemblages that reflect a climatic turnover: …

Stromatolites And Miss—Differences Between Relatives, N. Noffke, S. M. Awramik

OES Faculty Publications

Benthic microorganisms form highly organized communities called “biofilms.” A biofilm consists of the individual cells plus their extracellular polymeric substances (EPS). In marine and non-marine environments, benthic microbial communities interact with the physical sediment dynamics and other factors in the environment in order to survive. This interaction can produce distinctive sedimentary structures called microbialites. Binding, biostabilization, baffling, and trapping of sediment particles by microorganisms result in the formation of microbially induced sedimentary structures (MISS); however, if carbonate precipitation occurs in EPS, and these processes happen in a repetitive manner, a multilayered build-up can form—stromatolites. Stromatolites and MISS are first found …

Microbially Induced Sedimentary Structures Recording An Ancient Ecosystem In The Ca. 3.48 Billion-Year-Old Dresser Formation, Pilbara, Western Australia, Nora Noffke, Daniel Christian, David Wacey, Robert M. Hazen

OES Faculty Publications

Microbially induced sedimentary structures (MISS) result from the response of microbial mats to physical sediment dynamics. MISS are cosmopolitan and found in many modern environments, including shelves, tidal flats, lagoons, riverine shores, lakes, interdune areas, and sabkhas. The structures record highly diverse communities of microbial mats and have been reported from numerous intervals in the geological record up to 3.2 billion years (Ga) old. This contribution describes a suite of MISS from some of the oldest well-preserved sedimentary rocks in the geological record, the early Archean (ca. 3.48 Ga) Dresser Formation, Western Australia. Outcrop mapping at the meter to …

Distributions Of Particulate Heme B In The Atlantic And Southern Oceans- Implications For Electron Transport In Phytoplankton, Martha Gledhill, Eric P. Achterberg, David J. Honey, Maria C. Nielsdottir, Micha J.A. Rijkenberg

OES Faculty Publications

Concentrations of heme b, the iron-containing component of b-type hemoproteins, ranged from b concentrations were enhanced in the photic zone and decreased with depth. Heme b concentrations correlated positively with chlorophyll a (chl a) in the TNA (r=0.41, pb did not correlate with chl a in the IB or SS. In the IB and SS, stations with high-chlorophyll and low-nutrient (Fe and/or Si) concentrations exhibited low heme bconcentrations relative to particulate organic carbon (< 0.1 μmolmol^-1, and high chl a:heme b ratios (> 500). High chl a:heme b ratios resulted from relative decreases in …