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2008

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Articles 121 - 150 of 170

Full-Text Articles in Geology

Foundation Problems And Pyrite Oxidation In The Chattanooga Shale, Estill County, Kentucky, Warren H. Anderson Jan 2008

Foundation Problems And Pyrite Oxidation In The Chattanooga Shale, Estill County, Kentucky, Warren H. Anderson

Report of Investigations--KGS

Pyrite oxidation in the Chattanooga Shale has caused serious foundation problems in numerous buildings and structures in Estill County, Ky. Pyrite oxidizes and various secondary sulfates form when excavated shale or shale fill are used in foundations. These secondary sulfates are water- and humidity-sensitive and can form when only minor amounts of water are present in foundation materials. These sulfates form by crystal growth and expand by volume change, which causes subsequent soil expansion and heaving of any foundation materials when the materials are confined. Several structures have undergone expensive remediation to repair damaged sidewalks, floors, walls, and foundations. Zones …


Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke Jan 2008

Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke

OES Faculty Publications

Archean Earth history is very difficult to reconstruct. Until recently, only bacterial cells preserved in chert, microborings, and stromatolites provided the few clues to ancient life. Now, siliciclastic “microbially induced sedimentary structures” (MISS) are adding to our knowledge of both past life and paleoenvironments. MISS rise from the interaction of photoautotrophic microbial mats with physical sediment dynamics in siliciclastic, shallow-marine settings. Archean MISS can be understood through observations of living microbial mats and modern biotic-physical sedimentary processes. Such geobiological studies are key to the interpretation of the early evolution of prokaryotes. For example, the 2.9 Ga Pongola Supergroup, South Africa, …


A Faculty Workshop On Student Assessment, Iris M. Totten, Kirsten Nicolaysen, Sheryl Hodge, Mary S. Hubbard Jan 2008

A Faculty Workshop On Student Assessment, Iris M. Totten, Kirsten Nicolaysen, Sheryl Hodge, Mary S. Hubbard

Geosciences Faculty Publications

A faculty workshop was conducted that showcased assessment activities that could be incorporated into undergraduate and graduate geology courses. Fourteen different types of student assessment were presented. Workshop participants were asked to respond to questions about their familiarity and use of each type before and immediately following the workshop. In addition, they were asked to indicate how likely they would be to incorporate each type of assessment in their student grading practices in the future. Results suggest relatively high familiarity and use of the more traditional types of assessments (e.g., instructor- and commercially-produced pencil and paper exams, group projects, and …


Strike-Slip Fault Terminations At Seismogenic Depths: The Structure And Kinematics Of The Glacier Lakes Fault, Sierra Nevada United States, J. D. Kirkpatrick, Z. K. Shipton, James P. Evans, S. Micklethwaite, S. J. Lim, Peter R. Mckillop Jan 2008

Strike-Slip Fault Terminations At Seismogenic Depths: The Structure And Kinematics Of The Glacier Lakes Fault, Sierra Nevada United States, J. D. Kirkpatrick, Z. K. Shipton, James P. Evans, S. Micklethwaite, S. J. Lim, Peter R. Mckillop

Geosciences Faculty Publications

[1] Structural complexity is common at the terminations of earthquake surface ruptures; similar deformation may therefore be expected at the end zones of earthquake ruptures at depth. The 8.2 km long Glacier Lakes fault (GLF) in the Sierra Nevada is a left-lateral strike-slip fault with a maximum observed displacement of 125 m. Within the fault, pseudotachylytes crosscut cataclasites, showing that displacement on the GLF was accommodated at least partly by seismic slip. The western termination of the GLF is defined by a gradual decrease in the displacement on the main fault, accompanied by a 1.4 km wide zone of secondary …


Electron Donor Potential Of Eastern North Dakota Shale Formations, Ryan J. Salinas Klapperich Jan 2008

Electron Donor Potential Of Eastern North Dakota Shale Formations, Ryan J. Salinas Klapperich

Theses and Dissertations

Research involving a network of in situ mesocosms (ISM) in North Dakota, Minnesota, and Iowa has revealed significant variation in the denitrification capacity of aquifers in different regions of these states. One aquifer in particular, the Elk Valley Aquifer (EVA) of east-central North Dakota, has the highest concentrations of electron (e) donors (organic carbon -0.4%, pyrite as S -0.4%, and ferrous iron -0.3%) within its sediments and the highest rates of denitrification. The sediments at all of the ISM sites were deposited as outwash during the last Wisconsinan glaciation (-12ka), yet their e· donor concentrations vary. I suggest that the …


Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan Jan 2008

Correlation Of Electron Donor Concentrations In Sediments With Sediment Properties: New Providence, Iowa, Bijesh Maharjan

Theses and Dissertations

The concentrations of electron donors in aquifer sediments are important in understanding the fate and transport of redox-sensitive constituents in ground water, such as nitrate. In this study, 50 sediment samples were collected from below the water table from 11 boreholes at the US Geological Survey Agricultural Chemicals Transport site near New Providence, Iowa. All samples were analyzed for gravel, sand (coarse, medium, and fine), silt, clay, inorganic carbon contents and for the following electron donors: organic carbon, ferrous iron, and inorganic sulfide. A subset of sediment samples was analyzed for organic sulfur, but all of the 14 samples were …


The Effect Of Chloride Ion On Heavy Metal Partitioning And Transport In An Urban Watershed: Patroon Creek, Albany, Ny, Charles Begeal Jan 2008

The Effect Of Chloride Ion On Heavy Metal Partitioning And Transport In An Urban Watershed: Patroon Creek, Albany, Ny, Charles Begeal

Geology Theses and Dissertations

Road deicing salt use in the United States has increased extensively over the last 60 years with urbanization and a need to keep roads safe during winter months. This increase has caused an overall increase in the base concentration of Cl- in streams near roads that receive deicing salts. Many of these streams are in the Northeast United States where extensive industrialization has led to the pollution of soils, sediments, and surface waters by heavy metals. This study addresses the effect that chloride concentration has on fluvial transport and partitioning of heavy metals between the dissolved and suspended phases in …


Apparent Tolerance Of Turkey Vultures (Cathartes Aura) To The Non-Steroidal Anti-Inflammatory Drug Diclofenac, Barnett A. Rattner, Maria A. Whitehead, Grace Gasper, Carol U. Meteyer, William A. Link, Mark A. Taggart, Andrew A. Meharg, Oliver H. Pattee, Deborah J. Pain Jan 2008

Apparent Tolerance Of Turkey Vultures (Cathartes Aura) To The Non-Steroidal Anti-Inflammatory Drug Diclofenac, Barnett A. Rattner, Maria A. Whitehead, Grace Gasper, Carol U. Meteyer, William A. Link, Mark A. Taggart, Andrew A. Meharg, Oliver H. Pattee, Deborah J. Pain

United States Geological Survey: Staff Publications

The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose ~0.1–0.2 mg/kg), evoking visceral gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to …


A Multi-Tracer Study Of Saltwater Origin, Cross-Formational Flow, And The Geochemical Evolution Of Groundwater In The Southern High Plains Aquifer Along The Western Caprock Escarpment, East-Central New Mexico, Jeff Langman Jan 2008

A Multi-Tracer Study Of Saltwater Origin, Cross-Formational Flow, And The Geochemical Evolution Of Groundwater In The Southern High Plains Aquifer Along The Western Caprock Escarpment, East-Central New Mexico, Jeff Langman

Open Access Theses & Dissertations

Sustainable management of groundwater resources requires sufficient knowledge of the distribution of fresh and saline groundwater and the processes affecting saltwater intrusion that may influence the beneficial use of groundwater. A hydrogeologic investigation that coupled various chemical and isotopic tracers, including 3H/3He, 14C, δD, δ18O, 87Sr/86Sr, and δ11B, with the physical characteristics of the aquifer was conducted to determine source waters, the origin of saltwater and its influence through cross-formational flow, and water-rock interactions in the Southern High Plains aquifer along the Western Caprock Escarpment. Sub-aquifers or local flow systems are present along the Western Caprock Escarpment, and the study …


Using Elliptical Fourier Analysis To Compare Size Of Morphospace Occupation Between Modern Edentulous Freshwater Unionoid Mussels And The Fossils At L6516 (Slope County, North Dakota, Usa), With Remarks On Preservation, Mathew E. Burton-Kelly Jan 2008

Using Elliptical Fourier Analysis To Compare Size Of Morphospace Occupation Between Modern Edentulous Freshwater Unionoid Mussels And The Fossils At L6516 (Slope County, North Dakota, Usa), With Remarks On Preservation, Mathew E. Burton-Kelly

Theses and Dissertations

The purpose of this project was to use outline morphometric techniques to determine the number of freshwater mussel taxa present at locality L6516 (“Das Goods”),which is located in Cretaceous strata in the basal Ludlow Member of the Fort Union Formation in Slope County, North Dakota, U.S.A. Secondary goals were to improve the outline morphometric procedures that have been previously used to characterize fossil and extant freshwater mussels, and to describe in more detail the preservation of the edentulous unionoid specimens from the Das Goods area.

Outlines of individual mussel valves were used for morphometric analyses due to lack of preserved …


Age And Structure Of The San Jacinto And San Felipe Fault Zones, And Their Lifetime Slip Rates, Susanne U. Janecke, R. J. Dorsey, B. Belgarde Jan 2008

Age And Structure Of The San Jacinto And San Felipe Fault Zones, And Their Lifetime Slip Rates, Susanne U. Janecke, R. J. Dorsey, B. Belgarde

Geosciences Faculty Publications

No abstract provided.


Multiple Sedimentary Sequences, Bird Tracks And Lagoon Beaches In Last Interglacial Oolites, Boiling Hole, North Eleuthera Island, Bahamas, Pascal Kindler, H. Allen Curran, Damiel Marty, Elias Samankassou Jan 2008

Multiple Sedimentary Sequences, Bird Tracks And Lagoon Beaches In Last Interglacial Oolites, Boiling Hole, North Eleuthera Island, Bahamas, Pascal Kindler, H. Allen Curran, Damiel Marty, Elias Samankassou

Geosciences: Faculty Publications

Our review of the last interglacial (Marine Isotope Stage 5e) stratigraphic record from the Boiling Hole exposure in northern Eleuthera Island, Bahamas, revealed the occurrence of two vertically stacked shallowing-upward sequences of oolitic coastal deposits showing beach facies at about 3 and 6 m above mean sea level, respectively. These beach strata dip towards the bank interior and the upper one includes a paleosurface on top of an oolitic grainstone bed with a 2-m-long bird trackway. These fossil beaches correspond to two distinctive sea-level highstands during the last interglacial that could have possibly reached +5 and +8 m above modem …


Geology Of Rum Cay, Bahamas: A Field Trip Guide, John E. Mylroie, James L. Carew, H. Allen Curran, Jonathan B. Martin, Thomas A. Rothfus, Neil E. Sealey, Fredrick D. Siewers Jan 2008

Geology Of Rum Cay, Bahamas: A Field Trip Guide, John E. Mylroie, James L. Carew, H. Allen Curran, Jonathan B. Martin, Thomas A. Rothfus, Neil E. Sealey, Fredrick D. Siewers

Geosciences: Faculty Publications

See other Smith authored Field Trip Guides of Gerace Research Centre.


Introduction To Special Section On Microcosms In Ice: The Biogeochemistry Of Cryoconite Holes, Andrew G. Fountain, Martyn Tranter Jan 2008

Introduction To Special Section On Microcosms In Ice: The Biogeochemistry Of Cryoconite Holes, Andrew G. Fountain, Martyn Tranter

Geology Faculty Publications and Presentations

Cryoconite holes are small, water filled, cylindrical melt-holes on glacial ice surface. Cryoconite, 'cold dust,' refers to the thin layer of sediment at the hole bottom. The holes form from surficial sediment patches that absorbs more solar radiation than the surrounding ice and which preferentially melt into the glacier forming a cylindrical water-filled hole. These holes form on the ice-covered, as opposed to snow covered, parts of glaciers world-wide, wherever there is sufficient energy for melting. Biogeochemically, cryoconite holes are interesting because the sediment is inncoculated with biologic material, a fraction of which thrives in the cryoconite environment of near-freezing …


Middle Crustal Ductile Deformation Patterns In Southern Tibet: Insights From Vorticity Studies In Mabja Dome, Jackie Langille Jan 2008

Middle Crustal Ductile Deformation Patterns In Southern Tibet: Insights From Vorticity Studies In Mabja Dome, Jackie Langille

All Master's Theses

Mabja Dome, southern Tibet, exposes mid-crustal rocks proposed to have originated from a southward flowing mid-crustal channel. Kinematic, mean kinematic vorticity (Wm), and metamorphic petrography analyses on these mid-crustal rocks were performed to test this hypothesis. Kinematic indicators show a transition with structural depth from top-north and top-south shear to solely top-south shear. Along the northernmost transects, Wm in schists and orthogneisses range from 0.52–0.84 (63–36% pure shear). Wm for quartzites ranges from 0.9–0.99 (27–1% pure shear). Deformation temperatures increase from ~450 °C in the chloritoid-zone to ~700 °C in the sillimanite-zone and were recorded between ~35–16 Ma. These patterns …


The Carbonatite-Hosted Apatite Deposit Of Jacupiranga, Se Brazil: Styles Of Mineralization, Ore Characterization And Association With Mineral Processing, Paula Regina Alves Jan 2008

The Carbonatite-Hosted Apatite Deposit Of Jacupiranga, Se Brazil: Styles Of Mineralization, Ore Characterization And Association With Mineral Processing, Paula Regina Alves

Masters Theses

"The carbonatite-hosted apatite deposit of Jacupiranga is located in southeastern Brazil. The major styles of apatite mineralization are veins or veinlets, small pods or patches, disseminated apatite, and massive aggregates (locally). The concentration of apatite involves grinding of the carbonatite, removal of magnetite with a magnet drum, size classification with cyclones, and flotation to suppress carbonates and collect apatite. Samples of carbonatite were collected from more recent exposures of the mine and drill holes. This study utilized a variety of microscopy methods, namely transmitted and reflected light, cathodoluminescence (CL), and scanning electron microscopy (with wavelength-dispersive spectrometers for mineral compositions)"--Abstract, page …


Textural Analysis Of A Rhyolite Dike Of The Southern Oklahoma Aulacogen At Medicine Park, Oklahoma, Sean Patrick O'Donnell Jan 2008

Textural Analysis Of A Rhyolite Dike Of The Southern Oklahoma Aulacogen At Medicine Park, Oklahoma, Sean Patrick O'Donnell

Masters Theses

"Detailed analysis of the modal abundance and crystal size distribution (CSD) of glomerocrystic quartz and alkali feldspar phenocrysts in a porphyritic "rhyolite" dike at Medicine Park, Oklahoma were integrated with known phase relationships in the system SiO₂-NaAlSi₃O₈-KAlSi₃-O₈-H₂O to constrain the history of this intrusion"--Abstract, page iv.


Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade Jan 2008

Lateral Reservoir Compartmentalization Of The Woodford Shale In The Arkoma Basin, Southeastern Oklahoma, Adedapo Omotunde Ajibade

Masters Theses

"Analysis of geochemistry, mineralogy, total organic content (TOC) and rock evaluation pyrolysis on Woodford Shale well cuttings taken from a horizontal well (Quaid 13-30H) drilled in the Arkoma Basin (Pittsburg County), Oklahoma shows no significant variation in the thermal maturity, type, and/or quantity of organic matter. This is interpreted to mean that the organic matter of the Woodford Shale is relatively homogeneous and has all undergone similar thermal history. In addition, the analysis shows that there are lateral variations in the gas geochemistry in which the shale appears to be broken up into sections, some of which are more enhanced …


Biogenic Macroporosity And Lts Lattice Boltzmann Method Permeability In The Karst Biscayne Aquifer, Kevin J. Cunningham, Michael C. Sukop, Haibo Huang, Pedro F. Alvarez, H. Allen Curran, Michael A. Wacker, Lee J. Florea, Robert A. Renken, Joann F. Dixon Jan 2008

Biogenic Macroporosity And Lts Lattice Boltzmann Method Permeability In The Karst Biscayne Aquifer, Kevin J. Cunningham, Michael C. Sukop, Haibo Huang, Pedro F. Alvarez, H. Allen Curran, Michael A. Wacker, Lee J. Florea, Robert A. Renken, Joann F. Dixon

Geosciences: Faculty Publications

We focus on two major problems in the study of paleokarst of the Biscayne aquifer in southeastem Florida: ( 1 ), current conceptual models of karst aquifers do not adequately characterize much of the eogenetic rnacropore system within the carbonate rocks of the Biscayne aquifer, and (2) standard laboratory core-analysis rnethods cannol be used lo accurately measure the permeability of highly macroporous carbonate core samples.


An Evaluation Of Earthquake Ground-Motion Site Effects At Two Sites Underlain By Deep Soils In Western Kentucky, Jonathan Larry Mcintyre Jan 2008

An Evaluation Of Earthquake Ground-Motion Site Effects At Two Sites Underlain By Deep Soils In Western Kentucky, Jonathan Larry Mcintyre

University of Kentucky Master's Theses

Six earthquake acceleration time histories were used to evaluate the groundmotion response of two sites, VSAP and VSAS, near the New Madrid Seismic Zone. These earthquakes ranged in magnitude from Mw 3.6 to Mw 5.2 and were located 46 to 173 km away from the recording instruments. These two sites are underlain by thick sequences (100 and 590 m) of unlithified soil that have been shown to greatly influence earthquake ground motions.

Near-surface soil dynamic properties were characterized at the two sites using seismic SH-wave refraction, P-S suspension logging, borehole electrical logs, and geotechnical logging methods. The soil …


Subsurface Characterization And Seuqence Stratigraphy Of Late Mississippian Strata In The Black Warrior Basin, Alabama And Mississippi, Carrie A. Kidd Jan 2008

Subsurface Characterization And Seuqence Stratigraphy Of Late Mississippian Strata In The Black Warrior Basin, Alabama And Mississippi, Carrie A. Kidd

University of Kentucky Master's Theses

A depositional framework for the Mississippian (Chesterian) Pride Mountain Formation/Hartselle Sandstone clastic tongue and the lower Bangor Limestone carbonate ramp in the Black Warrior basin, Mississippi and Alabama, is constructed from approximately 250 geophysical well logs, 15 well cuttings descriptions, and outcrop data. The framework is based upon cross sections, isopach maps, and transgressive-regressive sequence stratigraphy.

The Lowndes-Pickens synsedimentary fault block controlled sediment dispersal in during Pride Mountain/Hartselle deposition. The basin filled from the southwest, which pushed the depocenter northeastward during Hartselle deposition. The Hartselle sub-basin is composed of the Hartselle barrier-island and back-barrier deposits to the southwest, including the …


Integrated Geophysical Imaging Of Subsurface Geologic Conditions Across A Contaminant Plume, Mccracken County, Kentucky, Cora A. Blits Jan 2008

Integrated Geophysical Imaging Of Subsurface Geologic Conditions Across A Contaminant Plume, Mccracken County, Kentucky, Cora A. Blits

University of Kentucky Master's Theses

Over 7.8 km of seismic reflection data and 2 km of electrical resistivity data were acquired, processed, and interpreted during this multi-method geophysical study. Objectives included the definition of geologic conditions underlying a contaminant plume in McCracken County, western Kentucky, and the determination of the potential for structural control on the rate and direction of plume migration. Both geophysical methods indicate the presence of multiple high-angle normal faults outlining a series of asymmetric grabens ranging in width from 160 m to almost 300 m and striking between N40°E and N45°E. There was agreement between the two methods on fault location …


Early Pleistocene Initiation And Structural Complexities Of The San Jacinto And San Felipe Fault Zones, Western Salton Trough: Part Ii, Susanne U. Janecke, R. J. Dorsey, B. Belgarde Jan 2008

Early Pleistocene Initiation And Structural Complexities Of The San Jacinto And San Felipe Fault Zones, Western Salton Trough: Part Ii, Susanne U. Janecke, R. J. Dorsey, B. Belgarde

Geosciences Faculty Publications

No abstract provided.


Iron Ooid Beds Of The Carolinefjellet Formation, Spitsbergen, Norway, Jeremy Mutrux, Harmon D. Maher Jr., Robert Duncan Shuster Jan 2008

Iron Ooid Beds Of The Carolinefjellet Formation, Spitsbergen, Norway, Jeremy Mutrux, Harmon D. Maher Jr., Robert Duncan Shuster

Geography and Geology Faculty Publications

Iron ooid beds are unusual deposits that have been linked to greenhouse conditions and the transgressive flooding of shallow shelves, and which were globally prevalent during certain periods. Within the marine, Aptian-Albian, Carolinefjellet Formation of Spitsbergen, chamosite ooids have been found within distinctive sandstone beds at six localities, and at a consistent stratigraphic position within the basal Dalkjegla Member. Distinctive characteristics include the iron ooids themselves, a coarser grain size, intercalation with silty siderites, grading, cross-beds indicating offshore or longshore transport, and a lack of burrowing. The enclosing sands display planar and hummocky crossstratification and abundant oscillation ripple marks, and …


Shear Wave Splitting And Mantle Flow Associated With The Deflected Pacific Slab Beneath Northeast Asia, Kelly H. Liu, Stephen S. Gao, Yuan Gao, Jing Wu Jan 2008

Shear Wave Splitting And Mantle Flow Associated With The Deflected Pacific Slab Beneath Northeast Asia, Kelly H. Liu, Stephen S. Gao, Yuan Gao, Jing Wu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A total of 361 SKS and five local S wave splitting measurements obtained at global and regional seismic network stations in NE China and Mongolia are used to infer the characteristics of mantle fabrics beneath northeast Asia. Fast polarization directions at most of the stations in the western part of the study area are found to be consistent with the strike of local geological features. The dominant fast directions at the eastern part, beneath which seismic tomography and receiver function studies revealed a deflected slab in the mantle transition zone (MTZ), are about 100° from north, which are almost exactly …


A Stratigraphic And Depositional Interpretation Of A Sand Quarry In Middle Georgia, Jessica Taylor Jan 2008

A Stratigraphic And Depositional Interpretation Of A Sand Quarry In Middle Georgia, Jessica Taylor

Theses and Dissertations

Analysis of sediments from two sand quarries in Mauk, Georgia indicate braided stream environment. Sediment samples of both Pleistocene and Cretaceous age were collected, sedimentary features such as trough cross-bedding along with laminar bedding were recorded, and photos were taken to document the scale and stratigraphic sequences of the sediments. Petrified wood was collected throughout the two sand quarries indicating a terrestrial origin. Post-depositional modifications seen at some of sites include load and flame structures. Sediment samples were examined for grain-size distributions and other sediment textures.


Glacial Deposits, Vol. 36, 2007-2008, Department Of Geography-Geology Jan 2008

Glacial Deposits, Vol. 36, 2007-2008, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Geochemical Analysis Of Ironstone Preserved Molluscan Fossils Of The Hell Creek Formation (Cretaceous) And Ludlow Member Of The Fort Union Formation (Paleogene) Of Southwestern North Dakota, Tanya P. Justham Jan 2008

Geochemical Analysis Of Ironstone Preserved Molluscan Fossils Of The Hell Creek Formation (Cretaceous) And Ludlow Member Of The Fort Union Formation (Paleogene) Of Southwestern North Dakota, Tanya P. Justham

Theses and Dissertations

The uppermost Cretaceous Hell Creek Formation and Paleocene Ludlow Member of the Fort Union Formation in easternmost Montana and western North Dakota produce ironstone preserved freshwater molluscan fossils. Ironstone preserved mollusks are associated with ironstone nodules, which have been described as composed of iron carbonate, iron oxide, or manganese oxide by various researchers. To date, the exact composition of the ironstone preservation has not been satisfactorily determined to allow agreement between researchers. Freshwater mollusk fossils, preserved as ironstone external casts, molds, and steinkerns, tend to be highly weathered. The poor preservation of the fossils has resulted in little professional interest, …


Evaluation Of Spring Flow, Bacterial Contamination, And Distribution Of Fresh Water Resources In The Vicinity Of Verrettes, Haiti, Peter Wampler, Andrew Sisson Jan 2008

Evaluation Of Spring Flow, Bacterial Contamination, And Distribution Of Fresh Water Resources In The Vicinity Of Verrettes, Haiti, Peter Wampler, Andrew Sisson

Student Summer Scholars Manuscripts

The purpose of this study was to gain a better understanding of fresh water springs used as the primary source of potable water in rural Haiti. Field data was collected during the summer of 2008 near Verrettes, Haiti, approximately 120 km north of Port au Prince. GPS locations of 29 springs were recorded within the 87 sq km study area. Two water samples at each spring were taken for bacterial analysis: one sample was submitted to a local hospital and a duplicate sample was cultured using Coliscan© Easygel© Kits. Both capped and uncapped springs were sampled to determine whether capping …


Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton Jan 2008

Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surficial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.