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2008

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Articles 91 - 120 of 529

Full-Text Articles in Earth Sciences

In Memoriam Sep 2008

In Memoriam

Studia UBB Geologia

No abstract provided.


Geochemical Sediments & Landscape; Cave Geology; Karst Hydrogeology And Geomorphology, Bogdan P. Onac Sep 2008

Geochemical Sediments & Landscape; Cave Geology; Karst Hydrogeology And Geomorphology, Bogdan P. Onac

Studia UBB Geologia

No abstract provided.


Events, Sorin Filipescu, Dana Pop Sep 2008

Events, Sorin Filipescu, Dana Pop

Studia UBB Geologia

No abstract provided.


Water Quality Impacts From Agricultural Land Use In Karst Drainage Basins Of Sw Kentucky And Sw China, Chris Groves, Ted Baker Sep 2008

Water Quality Impacts From Agricultural Land Use In Karst Drainage Basins Of Sw Kentucky And Sw China, Chris Groves, Ted Baker

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes, and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into karst subsurface fluvial systems are often very similar to the concentrations surfacing at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be given to water quality impacts …


Lateral Circulation And Suspended Sediment Transport In A Curved Estuarine Channel: Winyah Bay, Sc, Usa, Yong Hoon Kim, George Voulgaris Sep 2008

Lateral Circulation And Suspended Sediment Transport In A Curved Estuarine Channel: Winyah Bay, Sc, Usa, Yong Hoon Kim, George Voulgaris

Faculty Publications

Shipborne vertical profiles of flow and suspended sediment concentration collected on a transect, across a curved, nonsymmetrical estuarine channel are presented. Analysis of the transient cross-channel momentum balance equation shows that the lateral circulation pattern is controlled by the interaction between centrifugal and lateral baroclinic forcings although those two might not be necessarily in balance as suggested earlier by Seim and Gregg (1997). Instead, differential along-channel advection and local acceleration appear to influence greatly lateral circulation dynamics. During ebb when the water column is highly stratified, the interaction between centrifugal acceleration and opposite-directed lateral baroclinic forcing results in weak lateral …


Ft-Raman And Ft-Infrared Investigations Of Archaeological Artefacts From Foeni Neolithic Site (Banat, Romania), Simona Cîntă Pînzaru, Dana Pop, Loredana Nemeth Sep 2008

Ft-Raman And Ft-Infrared Investigations Of Archaeological Artefacts From Foeni Neolithic Site (Banat, Romania), Simona Cîntă Pînzaru, Dana Pop, Loredana Nemeth

Studia UBB Geologia

An impressive collection of chert artefacts from the Foeni Neolithic archaeological site (Timiş County, Banat region, Romania) is hosted by the Banat Museum in Timişoara. A representative set of seven specimens was non-destructively investigated using FT-Raman and ATR-FT-IR spectroscopy. The research was carried out for checking if these readily-available, non-destructive, fast, and cheap methods, which do not require preliminary sample preparation could provide significant information for characterizing the mineral composition of chert artefacts. Based on vibrational data, it was confirmed that the raw material was represented by microcrystalline quartz and moganite, with local concentrations of accessory minerals (calcite, dolomite, and …


New Bryozoa From The Sarmatian (Middle Miocene) Deposits Of The Cerna-Strei Depression, Romania, Kamil Zágoršek, Lóránd Silye, Botond Szabó Sep 2008

New Bryozoa From The Sarmatian (Middle Miocene) Deposits Of The Cerna-Strei Depression, Romania, Kamil Zágoršek, Lóránd Silye, Botond Szabó

Studia UBB Geologia

A new species of the Sarmatian bryozoan, Crisia romanica sp. nov., is described from Sarmatian (Middle Miocene) sediments of the Cerna-Strei Depression, near Răcăştia, Romania. The new species differs from all other known species of Crisia by having a frontal elongated gonozooecium with a prominent oeciopore situated on a short oeciostome. Crisia romanica sp. nov. is accompanied by Annectocyma corrugata (REUSS, 1869) occurring in a section nearby. The bryozoans found indicate normal marine conditions in the Cerna-Strei Depression during the Sarmatian.


Biostratigraphy Of The Cenomanian-Turonian Boundary In The Eastern Carpathians (Dâmboviţa Valley): Preliminary Observations, Claudia Cetean, Ramona Balc, Michael A. Kaminski, Sorin Filipescu Sep 2008

Biostratigraphy Of The Cenomanian-Turonian Boundary In The Eastern Carpathians (Dâmboviţa Valley): Preliminary Observations, Claudia Cetean, Ramona Balc, Michael A. Kaminski, Sorin Filipescu

Studia UBB Geologia

Planktonic and benthic foraminiferal assemblages from an Upper Albian to Lower Turonian interval in the East Carpathians were investigated in a well and in an outcrop from the Stoeneşti – Cetăţeni area (Dâmboviţa Valley), Romania. The benthic foraminiferal extinction that occurred at the Cenomanian/Turonian boundary and the first stage of the faunal recovery are documented here for the first time in the Romanian Carpathians. Bioevents and changes in the foraminiferal record from this area show that low oxygen conditions occured already in the Late Cenomanian, as suggested by the presence of radiolarian-rich shales. Impoverished assemblages of small, thin walled agglutinated …


Plant Macrofossils Analysis From Steregoiu Nw Romania: Taphonomy, Representation, And Comparison With Pollen Analysis, Angelica N. Feurdean, Ole Bennike Sep 2008

Plant Macrofossils Analysis From Steregoiu Nw Romania: Taphonomy, Representation, And Comparison With Pollen Analysis, Angelica N. Feurdean, Ole Bennike

Studia UBB Geologia

This paper presents the results of macrofossil analysis from the Steregoiu sequence in the Gutaiului Mountains covering the last 8,000 cal BP. The studied peat deposit is characterized by abundant macrofossils. Their diversity is, however, low with most macrofossils coming from plants that grew on the mire and in the forest surrounding the basin (Carex spp., Cyperus sp., Urtica dioica, Potentilla erecta, Filipendula ulmaria, Rubus idaeus, Lycopus europaeus). The concentration of Picea abies macrofossils correlates partially well with its pollen percentages, and only when it has been present on the bog surface. The absence of macrofossils from deciduous trees, which …


Sequential Sorption Of Lead And Cadmium In Three Tropical Soils, Chip Appel, Lena Q. Ma, Roy D. Rhue, William Reve Sep 2008

Sequential Sorption Of Lead And Cadmium In Three Tropical Soils, Chip Appel, Lena Q. Ma, Roy D. Rhue, William Reve

Earth and Soil Sciences

It is important to examine mechanisms of Pb and Cd sorption in soils to understand their bioavailability. The ability of three tropical soils to retain Pb, Cd, and Ca was evaluated. The objectives of this study were to (1) determine the extent to which soil sorption sites are metal specific, (2) investigate the nature of reactions between metals and soil surfaces, and (3) identify how metals compete for sorption sites when they are introduced to soils sequentially or concurrently. Lead was shown to be much less exchangeable than Cd and inhibited Cd sorption. Cadmium had little effect on Pb sorption, …


Kernel Density Estimation Of Traffic Accidents In A Network Space, Zhixiao Xie, Jun Yan Sep 2008

Kernel Density Estimation Of Traffic Accidents In A Network Space, Zhixiao Xie, Jun Yan

Earth, Environmental, and Atmospheric Sciences Faculty Publications

A standard planar Kernel Density Estimation (KDE) aims to produce a smooth density surface of spatial point events over a 2-D geographic space. However, the planar KDE may not be suited for characterizing certain point events, such as traffic accidents, which usually occur inside a 1-D linear space, the roadway network. This paper presents a novel network KDE approach to estimating the density of such spatial point events. One key feature of the new approach is that the network space is represented with basic linear units of equal network length, termed lixel (linear pixel), and related network topology. The use …


Gsi: Geo Scene Investigation! On-Site Programming (Grade 7), Discover Mojave: Forever Earth Sep 2008

Gsi: Geo Scene Investigation! On-Site Programming (Grade 7), Discover Mojave: Forever Earth

Curriculum materials (FE)

GSI: Geo Scene Investigation! introduces students to the differences between observations and interpretations and to some of the fundamental principles of geology. Students identify specific geologic processes and landforms in the landscape surrounding them at Lake Mead National Recreation Area (NRA) by solving mysteries with a set of geology-related clues.


Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella Sep 2008

Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella

Public Policy and Leadership Faculty Research

Gambel oak (Quercus gambelii) clones have several different growth forms in southwestern ponderosa pine (Pinus ponderosa) forests, and these growth forms each provide unique wildlife habitat and resource values. The purposes of this note are to review published growth-form classifications for Gambel oak, provide examples of ecological effects of different growth forms, and summarize management strategies for promoting desired growth forms. Four different growth-form classifications have been published, which generally recognize variants of three basic forms: shrubby thickets of small-diameter stems, pole-sized clumps, and large trees. These growth forms exemplify ecological and management tradeoffs. For example, shrubby forms provide browse …


Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer Sep 2008

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Research

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …


Lime For High Rainfall Pastures: Above 800mm Average Annual Rainfall, Mike Bolland, Bill Russell Sep 2008

Lime For High Rainfall Pastures: Above 800mm Average Annual Rainfall, Mike Bolland, Bill Russell

Bulletins 4000 -

Conventional agriculture acidifies soil. As your soil becomes more acid, productive pasture species disappear and are replaced by species of low agricultural value. It is a waste of money to apply expensive fertiliser to pastures which are inherently poorly productive because they are growing in an acid soil.

The paper examines the types of lime available, how to select lime for quality and when and how much lime to apply. Maganese toxity and aluminum toxicity are examine, how to test your soil, and affect of soil acidity on bacteria and other microorgansims.


Optlime, A Bioecenomic Model Of Soil Acidity Management In Agricultural Systems, Chris Gazey Sep 2008

Optlime, A Bioecenomic Model Of Soil Acidity Management In Agricultural Systems, Chris Gazey

All other publications

Optlime is a model that represents the essential biological, physical and economic factors related to soil acidity management in Western Australia. The model allows users to define site and soil characteristics for an acidic scenario and then simultaneously assess likely outcomes for 2 different lime sources and application strategies. With and without liming scenarios are examined over a 20 year simulation so as to capture the long-term impacts of soil acidity management. Output provided allows you to examine the likely effect of liming on pH, exchangeable aluminium, yields, and profits. An investment appraisal is provided to show you how liming …


Cancellation Of Spurious Arrivals In Green’S Function Extraction, Kasper Van Wijk Sep 2008

Cancellation Of Spurious Arrivals In Green’S Function Extraction, Kasper Van Wijk

CGISS Publications and Presentations

The extraction of the Green's function by cross correlation of waves recorded at two receivers nowadays finds much application. We show that for an arbitrary small scatterer, the cross terms of scattered waves give an unphysical wave with an arrival time that is independent of the source position. This constitutes an apparent inconsistency because theory predicts that such spurious arrivals do not arise, after integration over a complete source aperture. This puzzling inconsistency can be resolved for an arbitrary scatterer by integrating the contribution of all sources in the stationary phase approximation to show that the stationary phase contributions to …


Ground-Penetrating Radar And Thermal Modeling Of Active Layer Thaw Beneath Arctic Streams, Troy Richard Brosten Sep 2008

Ground-Penetrating Radar And Thermal Modeling Of Active Layer Thaw Beneath Arctic Streams, Troy Richard Brosten

Boise State University Theses and Dissertations

Seasonal thaw depth beneath arctic streams significantly impacts physical and biological processes within arctic stream environments. The impact of greater seasonal thaw for extended periods of time can alter ecosystems that have, in the past, resulted from more prevalent permafrost environments. Effects of climatic change on arctic stream environments necessitate the need for more information on characteristics of seasonal thaw and processes that occur within the thawed layer. Multiple ground-penetrating radar (GPR) methods and one-dimensional (1D) thermal modeling were used to investigate seasonal thaw beneath arctic streams and determine the dominant thermal process.

Study sites were selected to include stream …


Loess Record Of The Pleistocene–Holocene Transition On The Northern And Central Great Plains, Usa, Joseph A. Mason, Xiaodong Miao, P.R. Hanson, William C. Johnson, Peter M. Jacobs, Ronald J. Goble Sep 2008

Loess Record Of The Pleistocene–Holocene Transition On The Northern And Central Great Plains, Usa, Joseph A. Mason, Xiaodong Miao, P.R. Hanson, William C. Johnson, Peter M. Jacobs, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

Various lines of evidence support conflicting interpretations of the timing, abruptness, and nature of climate change in the Great Plains during the Pleistocene–Holocene transition. Loess deposits and paleosols on both the central and northern Great Plains provide a valuable record that can help address these issues. A synthesis of new and previously reported optical and radiocarbon ages indicates that the Brady Soil, which marks the boundary between late Pleistocene Peoria Loess and Holocene Bignell Loess, began forming after a reduction in the rate of Peoria Loess accumulation that most likely occurred between 13.5 and 15 cal ka. Brady Soil formation …


Pcor Partnership Atlas, Wesley D. Peck, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, John A. Harju, Melanie D. Jensen, Erin M. O'Leary, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Darin R. Damiani, John T. Litynski, David W. Fischer Sep 2008

Pcor Partnership Atlas, Wesley D. Peck, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, John A. Harju, Melanie D. Jensen, Erin M. O'Leary, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Darin R. Damiani, John T. Litynski, David W. Fischer

EERC Maps and Infographics

The Plains CO2 Reduction (PCOR) Partnership Atlas, revised 2nd edition, introduces global climate change and provides a regional profile of CO2 sources and potential sinks across the PCOR Partnership region. Carbon sequestration offers a promising set of technologies through which CO2 can be stored for long periods of time.


Direct Evidence From Anisotropy Of Magnetic Susceptibility For Lateral Melt Migration At Superfast Spreading Centers, R. J. Varga, Andrew J. Horst, J. S. Gee, J. A. Karson Aug 2008

Direct Evidence From Anisotropy Of Magnetic Susceptibility For Lateral Melt Migration At Superfast Spreading Centers, R. J. Varga, Andrew J. Horst, J. S. Gee, J. A. Karson

Natural Resources and Earth Sciences Faculty Research

Rare, fault‐bounded escarpments expose natural cross sections of ocean crust in several areas and provide an unparalleled opportunity to study the end products of tectonic and magmatic processes that operated at depth beneath oceanic spreading centers. We mapped the geologic structure of ocean crust produced at the East Pacific Rise (EPR) and now exposed along steep cliffs of the Pito Deep Rift near the northern edge of the Easter microplate. The upper oceanic crust in this area is typified by basaltic lavas underlain by a sheeted dike complex comprising northeast striking, moderately to steeply southeast dipping dikes. Paleomagnetic remanence of …


Erosion And Trail Building: A Case Study Of The East Tennessee State University Trail System., Joshua Callahan Aug 2008

Erosion And Trail Building: A Case Study Of The East Tennessee State University Trail System., Joshua Callahan

Electronic Theses and Dissertations

Natural and accelerated erosion from trail users affects the sustainability of trail systems. Designing and building sustainable trail systems will greatly decrease the effect that erosion has on a trail. Trails that allow multiple types of users, such as hiking and mountain biking, must be able to sustain both groups. At East Tennessee State University the trail system was originally designed for hiking. Mountain bikers have become the main user group on the trail system leading to erosion problems on certain areas of the trail due to trail design flaws. The study seeks to identify the problem areas of trail …


Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert Aug 2008

Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert

United States Geological Survey: Staff Publications

Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) …


A Microanalytical Approach To Understanding The Origin Of Cumulate Xenoliths From Mauna Kea, Hawaii, Megan Pickard Aug 2008

A Microanalytical Approach To Understanding The Origin Of Cumulate Xenoliths From Mauna Kea, Hawaii, Megan Pickard

Theses and Dissertations

Cumulate xenoliths erupted with alkalic hawaiite lavas from a postshield cinder cone on Mauna Kea, Hawaii include a variety of mafic and ultramafic rock types. Previous studies of major and trace element compositions of minerals in the xenoliths are interpreted to show transitional to alkalic magma parentages from the postshield stage, although any orthopyroxene-bearing xenoliths are considered to have tholeiitic parents. Major element compositions minerals were analyzed using the electron microprobe and trace element compositions of clinopyroxene grains were analyzed by laser ablation inductively coupled plasma mass spectrometry. In this study, major element compositions of clinopyroxene, olivine and plagioclase grains …


Magmatic Sulfur And Chlorine Abundances At Stromboli, Italy And Their Role In The Formation Of Vesicle-Hosted Metal Alloys, Nichelle Lynn Baxter Aug 2008

Magmatic Sulfur And Chlorine Abundances At Stromboli, Italy And Their Role In The Formation Of Vesicle-Hosted Metal Alloys, Nichelle Lynn Baxter

Theses and Dissertations

Strand et al. (2002) discovered small metal alloy grains rich in Cu, Co, and Sn (maximum size 150 µm) in vesicles of lava from Kilauea Volcano. These alloys are also found in basaltic rocks of several Italian volcanoes. To better understand the origin of these metal-rich grains, bombs from Stromboli Volcano were examined. Two bomb types were collected from Stromboli: pumiceous bombs and scoriaceous bombs. Bulk rock trace element geochemistry indicates that there are no significant differences in Cu, Co, or Sn (the three major components of the metal alloys) between the pumiceous and scoriaceous bombs. Comparison of olivine melt …


Stereospecificity In Glucose Consumption: A New Approach To Martian Life Detection, Vienna R. Saccomanno, Henry J. Sun Aug 2008

Stereospecificity In Glucose Consumption: A New Approach To Martian Life Detection, Vienna R. Saccomanno, Henry J. Sun

Undergraduate Research Opportunities Program (UROP)

In 1976, the Viking mission made a remarkable discovery: Martian soil was capable of decomposing an organic nutrient broth to carbon dioxide as if it contained live microorganisms. However, a biological interpretation of this finding is in apparent contradiction with the gas chromatograph-mass spectrometer aboard the Viking landers, which showed Martian soil to be devoid of indigenous organics. To reconcile these findings, it has been hypothesized that unknown abiotic oxidants, such as peroxide and superoxide, are present on Mars and that they were responsible for its soil reactivity. The objective of this research is to develop a life detection method …


Potential Antimicrobial Properties Of The Cyanobacterium Microcoleus Vaginatus In Relationship To The Moss Bryum Argenteum, Crystal Erickson, Lloyd Stark Aug 2008

Potential Antimicrobial Properties Of The Cyanobacterium Microcoleus Vaginatus In Relationship To The Moss Bryum Argenteum, Crystal Erickson, Lloyd Stark

Undergraduate Research Opportunities Program (UROP)

Biological soil crusts play important ecological roles in arid desert regions. These crusts cycle nutrients, prevent wind/water erosion, and form the basis of food chains and soil formation in desert communities. Primary components of these structures include two desert moss species Bryum argenteum and Syntrichia caninervis, and Microcoleus vaginatus, a cyanobacterium. Our Phase I experiment strongly suggests that in an environment of intense light, a condition of stress to Syntrichia caninervis, there is an increase in shoot regeneration when cyanobacteria are present compared to when they are absent. Microcoleus is a highly motile species and our lab observations of fewer …


Magnetic Ordering Phase Transitions Of Gd2sn2o7, Gordon Tam, Andrew Cornelius, Daniel Antonio Aug 2008

Magnetic Ordering Phase Transitions Of Gd2sn2o7, Gordon Tam, Andrew Cornelius, Daniel Antonio

Undergraduate Research Opportunities Program (UROP)

Pyrochlores with magnetic rare earth ions are a topic of interest due to unusual results brought about by their high degree of geometrical frustration. The lattice structure prevents the magnetic spin interactions from finding a single minimum energy state, which leads to a nonzero residual entropy[1]. By analyzing the heat capacity at low temperatures, the type of magnetic interaction can be determined and the temperatures at which long-range magnetic ordering and magnetic field induced splitting of energy states occur.


Modeling The Deformation Of Fayalite, Greg Hoth, Mike Brawner, Pamela Burnley Aug 2008

Modeling The Deformation Of Fayalite, Greg Hoth, Mike Brawner, Pamela Burnley

Undergraduate Research Opportunities Program (UROP)

We are studying how the mineral fayalite deforms under stress while it is subject to high pressures and temperatures. Specifically, we are analyzing x-ray diffraction spectra obtained from experiments with the D-DIA apparatus at Brookhaven national labs. By fitting peaks to the diffraction spectra, we can calculate the spacing between lattice planes of fayalite and so we can observe how this spacing changes over time as the crystal structure deforms We hope to show that this deformation can be modeled using an Elastic Plastic Self Consistent model. In such a model, the material is treated as a cluster of independently …


Phonon Density Of States Of Iron Solid Solutions At Ambient And High Pressures Using Nuclear Inelastic X-Ray Scattering (Nrixs), Samantha L. Combs, Elizabeth A. Tanis, Malcolm Nicol Aug 2008

Phonon Density Of States Of Iron Solid Solutions At Ambient And High Pressures Using Nuclear Inelastic X-Ray Scattering (Nrixs), Samantha L. Combs, Elizabeth A. Tanis, Malcolm Nicol

Undergraduate Research Opportunities Program (UROP)

Nuclear resonant inelastic x-ray scattering (NRIXS) of synchrotron radiation uses the energy transferred during the inelastic nuclear absorption of photons to determine phonon density of states for solid Mössbauer isotopes. This type of experiment can be conducted at ambient and high pressures with the use of a diamond anvil cell (DAC) and a rhenium gasket. Here, we are concerned with the phonon DOS of α-FePt 10% at pressures up to 30 GPa, as well as FeAl 4.3%, 6.4%, and 27.1% at ambient pressures. The iron samples used are doped in order to increase the pressure at which the alpha to …