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2004

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Articles 481 - 496 of 496

Full-Text Articles in Physical Sciences and Mathematics

Assessing Anthropogenic And Natural Impacts On Ghost Crab ( Ocypode Quadrata) Populations At Cape Hatteras National Seashore, North Carolina, Cynthia B. Landry Jan 2004

Assessing Anthropogenic And Natural Impacts On Ghost Crab ( Ocypode Quadrata) Populations At Cape Hatteras National Seashore, North Carolina, Cynthia B. Landry

Dissertations, Theses, and Masters Projects

No abstract provided.

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Design And Evaluation Of A Modified In Situ Mesocosm To Study Denitrification In The Karlsruhe Aquifer, Jason M. Warne Jan 2004

Design And Evaluation Of A Modified In Situ Mesocosm To Study Denitrification In The Karlsruhe Aquifer, Jason M. Warne

Theses and Dissertations

To simplify the in situ mesocosm (ISM) design given in Schlag (1999), a modified ISM was designed and built in which a 6-inch long sand point replaces three 16-inch diameter screens. The modified design also includes an optional submersible pump mounted on top of the ISM chamber, making it capable of applications at depths greater than those attainable using a peristaltic pump from the ground surface. Two ISMs, one the original design (0-ISM) and the other the modified design (M-ISM) with an optional submersible pump, were installed in the Karlsruhe aquifer, near Minot, ND, in late June, 2003. Tracer tests …

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A Comparison Of Land Use And Nonpoint Source Pollution In The Cedar River Tributaries In Iowa, Chad Levi Fields Jan 2004

A Comparison Of Land Use And Nonpoint Source Pollution In The Cedar River Tributaries In Iowa, Chad Levi Fields

Dissertations and Theses @ UNI

A comparative water analysis on major Cedar River tributaries was conducted to determine nutrient and sediment concentration, nutrient loads, and watershed land use during the spring and summer of 2002. The Cedar River watershed is located on a primarily agricultural land, and has a drainage area of20,242 km2. The watershed extends from southern Minnesota to southeastern Iowa, where it joins the Iowa River which subsequently flows into the Mississippi River. Past studies have concluded that the Cedar River contributes much of the nutrients entering the Mississippi River and the Gulf of Mexico. These nutrients then contribute to the zone of …

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Estimation Of Primary Production And Carbon Flux In Antarctic Coastal Waters: A Modeling Study, Hae-Cheol Kim Jan 2004

Estimation Of Primary Production And Carbon Flux In Antarctic Coastal Waters: A Modeling Study, Hae-Cheol Kim

OES Theses and Dissertations

This study presents results from models that are designed to simulate the underwater light field, to simulate phytoplankton primary production, and to estimate the fate of phytoplankton carbon in continental shelf waters of the west Antarctic Peninsula (WAP) and Ross Sea. Simulation of the underwater light field required derivation of new coefficient sets for power function-type cloud cover correction algorithms, which were found to be influenced by multiple reflections between the bottom of clouds and the surface. The coefficient sets indicate that the spectral effect of clouds on the properties of the surface irradiance was spectrally-neutral for wavelengths greater than …

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Nature And Dynamics Of Late Miocene/Early Pliocene Ice-Sheet Grounding Events On The Pacific Margin Of The Antarctic Pennisula Outer Continental Shelf, David C. Egan Jan 2004

Nature And Dynamics Of Late Miocene/Early Pliocene Ice-Sheet Grounding Events On The Pacific Margin Of The Antarctic Pennisula Outer Continental Shelf, David C. Egan

LSU Master's Theses

Package-3 unconformities identified by Bart and Anderson (1995) were mapped to evaluate their glacial unconformity interpretation using a regional grid of single channel seismic data from the Antarctic Peninsula outer continental shelf. Detailed correlations show many crosscutting relationships within Package 3 such that the unconformities and units they bound are not regionally continuous across the margin. Comparison of Package-3 unconformities with the modern bathymetry reveals that cross-shelf trough and bank morphology is absent, which indicates that ice streams probably did not exist on the shelf during Package-3 time. On the continental shelf, only the middle part of Package 3 is …

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Migmatization Of Archean Aluminous Metasediments From The Eastern Beartooth Mountains, Montana, U.S.A., Andrew T. Maas Jan 2004

Migmatization Of Archean Aluminous Metasediments From The Eastern Beartooth Mountains, Montana, U.S.A., Andrew T. Maas

LSU Master's Theses

Geothermobarometry, mineral compositions and textures, and thermodynamic models suggest biotite dehydration melting occurred in the peraluminous rocks of the eastern Beartooth Mountains. These Archean metapelitic migmatites are metatexites and diatexites, and have typical metamorphic assemblages of Qtz + Pl + Kfs + Bt + Sil +/- Grt +/- Crd. The subsequent in situ crystallization of the magma derived from the biotite dehydration created migmatitic leucosomes in the rocks. These leucosomes are primarily composed of quartz, plagioclase and potassium feldspar. Water derived from the dehydration of biotite was dissolved in the melted phase. Crystallization of the magma reintroduced this water to …

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Overlap Zones, Growth Faults, And Sedimentation: Using High Resolution Gravity Data, Livingston Parish, La, Carrie Alison Cazes Jan 2004

Overlap Zones, Growth Faults, And Sedimentation: Using High Resolution Gravity Data, Livingston Parish, La, Carrie Alison Cazes

LSU Master's Theses

In south Louisiana, parallel to the coast of the Gulf of Mexico, are belts of east-to-west trending, listric-normal faults with associated contemporaneous sedimentation and fault movement. The Tepetate-Baton Rouge Fault system in south-central Louisiana contains individual fault segments which are arcuate and overlap each other in map view, as seen on LiDAR data. Gravity survey data, with a sample spacing of 20 to 50 m, was collected across normal fault scarps. Structural ramps may form in the area between overlapping normal fault segments creating an east-to-west gradient. This gradient change may divert streams and provide areas for coarse-grained sediments to …

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Willamette River Basin Temperature Tmdl Model: Boundary Conditions And Model Setup, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells Jan 2004

Willamette River Basin Temperature Tmdl Model: Boundary Conditions And Model Setup, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and …

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Foreland Basins: Lithospheric Flexure, Plate Strength And Regional Stratigraphy, John Londono Jan 2004

Foreland Basins: Lithospheric Flexure, Plate Strength And Regional Stratigraphy, John Londono

LSU Doctoral Dissertations

Foreland basin subsidence through time is reproduced in this study, as the flexure of an elastic beam in an inviscid fluid under the vertical stress, caused by discrete-distributed loads. Thus, seismostratigraphic data from the Timor Sea peripheral foreland basin, in northwestern Australia, and the Putumayo retroarc foreland basin in the Colombian Andes, are forward modeled, at chronostratigraphic intervals, to assess the evolving geodynamic conditions of the basins. Results show that the accommodation in foreland basins varies as the depositional basement is vertically adjusted according to the regionally isostatic compensation of the lithosphere. Distributed tectonic (thrust belts) and sedimentary loads that …

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A Large Late Pleistocene Outburst Flood From Pluvial Lakes Alvord And Coyote Into The Owyhee River, Oregon, Deron Torrey Carter Jan 2004

A Large Late Pleistocene Outburst Flood From Pluvial Lakes Alvord And Coyote Into The Owyhee River, Oregon, Deron Torrey Carter

All Master's Theses

A large late-Pleistocene flood traveled into the Owyhee River as a result of a rise and subsequent outburst from pluvial Lake Alvord in southeastern Oregon. Lake Alvord breached Big Sand Gap after reaching an elevation of 1292 m, releasing 11.3 km3 into the adjacent Coyote Basin before stabilizing at an elevation of about 1280 m. Overflow then spilled out of the Coyote Basin through two outlets at 1278 m and into the Crooked Creek drainage of the Owyhee River. The flood created a series of deeply incised canyons, scabland topography and deposited numerous boulder bars containing imbricated clasts up to …

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Long-Range Downstream Effects Of Urban Runoff And Acid Mine Drainage In The Debed River, Armenia: Insights From Lead Isotope Modeling, Robert Kurkjian, Charles Dunlap, A. Flegal Dec 2003

Long-Range Downstream Effects Of Urban Runoff And Acid Mine Drainage In The Debed River, Armenia: Insights From Lead Isotope Modeling, Robert Kurkjian, Charles Dunlap, A. Flegal

Charles Dunlap

Lead concentrations and isotopic compositions measured along 80 km of the Debed River in the Republic of Armenia provide new insights into the geochemical and physical controls on riparian Pb transport by allowing comparison of the long-range, downstream impacts of acid mine drainage with runoff from an industrialized city. The modern background Pb concentration in Armenian surface waters is estimated to be ~0.01 lg/L, based on analyses of remote alpine rivers in Armenia. The lead concentration in the Debed River is 8 µg/L (800 times background) after passing through Vanadzor, the second largest industrial city in Armenia; it then decreases …

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Numerical Investigation Of Saturated Source Area Behavior At The Small Catchment Scale, Fred L. Ogden Dec 2003

Numerical Investigation Of Saturated Source Area Behavior At The Small Catchment Scale, Fred L. Ogden

Fred L. Ogden

The objective of this research is to explore the relationship between small catchment properties and the temporal growth and decay of saturated source areas (SSA). A simple physics-based hydrologic model, which we call the Sandbox model, is developed for this purpose. A thorough sensitivity analysis is undertaken to evaluate model response to variations in model parameters. Sandbox model output is compared to that from the semi-distributed conceptual model, TOPMODEL, a model with a wide spread acceptance. Plotting the temporal evolution of the extent of saturated source area versus catchment average soil water content dur- ing a number of wetting and …

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Toward A Climate Change Strategy For Pennsylvania, John C. Dernbach Dec 2003

Toward A Climate Change Strategy For Pennsylvania, John C. Dernbach

John C. Dernbach

No abstract provided.

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Lead In Residential Soil And Dust In A Mining And Smelting District In Northern Armenia: A Pilot Study, Varduhi Petrosyan, Anna Orlova, Charles E. Dunlap, Emil Babayan, Mark Farfel, Margrit Von Braun Dec 2003

Lead In Residential Soil And Dust In A Mining And Smelting District In Northern Armenia: A Pilot Study, Varduhi Petrosyan, Anna Orlova, Charles E. Dunlap, Emil Babayan, Mark Farfel, Margrit Von Braun

Charles Dunlap

This pilot study of sources of lead exposure in residential settings was conducted in a mining and smelting district in northern Armenia. Samples of exterior soil and dust and interior house dust were collected in and around apartment buildings in Alaverdi where the country’s largest polymetallic smelter is located, and in nearby mining towns of Aghtala and Shamlugh. The NITON XL- 723 Multi-Element XRF analyzer was used for lead testing. Lead levels in samples from Alaverdi were higher than those in Shamlugh and Aghtala. In all three towns, the highest lead levels were found in loose exterior dust samples, and …

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Introduction, Symposium Facing Climate Change: Opportunity And Tool For States, John C. Dernbach Dec 2003

Introduction, Symposium Facing Climate Change: Opportunity And Tool For States, John C. Dernbach

John C. Dernbach

No abstract provided.

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Making Sustainable Development Happen: From Johannesburg To Albany, John C. Dernbach Dec 2003

Making Sustainable Development Happen: From Johannesburg To Albany, John C. Dernbach

John C. Dernbach

No abstract provided.

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