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Articles 44731 - 44760 of 56626

Full-Text Articles in Physical Sciences and Mathematics

Perrennial Grassess - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey Jan 2005

Perrennial Grassess - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey

Agriculture reports

Farmers will be able to recognise landscape components on their farm that are at risk of salinity (current, imminent or future) and be aware of a range of available options available to them in managing this risk.


Introduction To Salinity - Workshop Development Guide For Facilitator, T M. Lacey Jan 2005

Introduction To Salinity - Workshop Development Guide For Facilitator, T M. Lacey

Agriculture reports

Participants will be able to recognise landscape components on their farm, which are at risk of salinity (current, imminent or future) and will be aware of a range of available options available to them to managing this risk.


Transient Detection And Modeling Of Continuous Geodetic Data, Walter Michael Szeliga Jan 2005

Transient Detection And Modeling Of Continuous Geodetic Data, Walter Michael Szeliga

All Master's Theses

Transient surface deformation has been observed by continuously operating Global Positioning System stations in the Puget Sound area during the past decade. This surface deformation is associated with processes occurring on or near the subducting plate boundary between the Juan de Fuca and North American plates. This thesis is composed of two studies of transient deformation along the Cascadia plate margin and a discussion of the methodologies employed in these studies. We model one 7-week episode of transient deformation that occurred during 2003 beneath the Puget Sound area. Additionally, we utilize a combination of continuous Global Positioning System and seismic …


The Twiggs Clay: Mineralogy, Origin, And Industrial Properties Of An Upper Eocene Opaline Claystone In The Coastal Plain Province Of Georgia, U.S., Lori G. Eversull Jan 2005

The Twiggs Clay: Mineralogy, Origin, And Industrial Properties Of An Upper Eocene Opaline Claystone In The Coastal Plain Province Of Georgia, U.S., Lori G. Eversull

LSU Doctoral Dissertations

The Twiggs Clay is an upper Eocene claystone found as discontinuous deposits downdip of the Fall Line in the Coastal Plain Province of eastern and central Georgia. A distinctive facies of the Twiggs is found in two lenses near the town of Wrens. The nature, origin, and potential commercial application of this resource are examined. Four strata and two mineralogic assemblages are recognized in the Wrens deposit. The lower three strata are near white in color and very low in density. These strata are mineralogically similar and are composed predominantly of disordered silica and smectite. The smectite is dioctahedral, and …


Land Evaluation Standards For Land Resource Mapping : Assessing Land Qualities And Determining Land Capability In South-Western Australia, Dennis Van Gool, Peter J. Tille, Geoff Allen Moore Jan 2005

Land Evaluation Standards For Land Resource Mapping : Assessing Land Qualities And Determining Land Capability In South-Western Australia, Dennis Van Gool, Peter J. Tille, Geoff Allen Moore

Resource management technical reports

This report describes the standard method for attributing and evaluating conventional land resource survey maps in the south-west agriculture region of Western Australia so that strategic decisions about the management, development and conservation of land resources can be based on the best information available. The standards described are similar to the land suitability assessment (stage one of the two stage) methods described by the Food and Agriculture Organisation (FAO, 1976, 1983).


Wagin-Woodanilling (Zone 5) : Catchment Appraisal 2005, K Ohlsen, T Schulz, T W. Mathwin, Gina Pemberton, Henry Brockman, J Firth, Mitchell Davies, Heather M. Percy Jan 2005

Wagin-Woodanilling (Zone 5) : Catchment Appraisal 2005, K Ohlsen, T Schulz, T W. Mathwin, Gina Pemberton, Henry Brockman, J Firth, Mitchell Davies, Heather M. Percy

Resource management technical reports

The aim of this report is to assess the current extent of salinity and other natural resource degradation issues and provide landholders with the best current management options to address natural resource management issues and enhance sustainable agricultural production.


Step Workshops - Guide For Facilitators, Department Of Agriculture And Food, Western Australia Jan 2005

Step Workshops - Guide For Facilitators, Department Of Agriculture And Food, Western Australia

Agriculture reports

The STEP workshops can be run as independent modules or as part of the ?A Million Hectares for the Future? workshop series of which the overarching learning outcome is: Participants will be able to identify and make informed decisions to profitably manage salinity on their farms. Outlines the preferred pathway for the modules in the Million Hectares for the Future series.


Assessing Recharge And Discharge Across The Prairie Pothole Landscape: Application Of Spatial Hydrological Data And Statistical Analysis In A Groundwater Flow Model, Christopher D. Laveau Jan 2005

Assessing Recharge And Discharge Across The Prairie Pothole Landscape: Application Of Spatial Hydrological Data And Statistical Analysis In A Groundwater Flow Model, Christopher D. Laveau

Theses and Dissertations

Quantifying the spatial and temporal dynamics between groundwater recharge, discharge, and wetlands is a necessary step to develop effective water management strategies. Wetlands in the northern Great Plains play a role in flood control, water supply, and regional ecology. The water budget of a wetland in the northern prairies is often an unequal balance between moisture input and output in which the permanence of a wetland depends on its groundwater budget. Identifying and quantifying groundwater recharge and discharge zones has applications in predicting the spatial and temporal distribution of wetlands.

The current work involved the application of a groundwater model …


Geomechanics Applied To Reservoir Development In The Coso Geothermal Field, Andrew J. Nygren Jan 2005

Geomechanics Applied To Reservoir Development In The Coso Geothermal Field, Andrew J. Nygren

Theses and Dissertations

The Coso geothermal field is located approximately 220 kilometers north of Los Angeles, CA. In 2002, a project began to develop the east flank of the Coso geothermal field into an enhanced geothermal system (EGS); in such a system water is injected via injection well(s) into hot dry basement rock through naturally occurring or stimulated fractures. The injected water gathers heat from the reservoir rock before being extracted for direct use or energy production. To develop such a reservoir, adequate understanding of the reservoir geomechanics is necessary. This thesis investigates the state of stress and rock fractures, the existing permeable …


The Effect Of Sample Size On Rapid Bioassessment Scores And Management Efficiency, Uttam Kumar Rai Jan 2005

The Effect Of Sample Size On Rapid Bioassessment Scores And Management Efficiency, Uttam Kumar Rai

Theses and Dissertations

The rapid bioassessment method for stream bio monitoring generally uses a fixed count of 200 macro invertebrates as the standard subsample size. This number has been argued to be too small to provide accurate estimates on the richness of macro invertebrate communities and is believed to give misleading information pertaining to stream health. In this study, I used data collected from multiple habitats from 29 streams located in several subecoregions of Georgia to examine how the rapid bioassessment scores perform across subsample sizes of 100, 200, and 300 organisms. Subsample sizes of 100 and 200 organisms were found to underestimate …


Step-Pool Morphology Of A Wilderness Headwater Stream Of The Buffalo River, Arkansas, Aaron M. Nickolotsky Jan 2005

Step-Pool Morphology Of A Wilderness Headwater Stream Of The Buffalo River, Arkansas, Aaron M. Nickolotsky

MSU Graduate Theses

Step-pool and cascade morphology reflect the geological and climatic factors affecting channels in mountain watersheds. This study uses longitudinal and cross-section surveys of a headwater stream in the Boston Mountains of the Ozarks Plateau region in northwest Arkansas to describe channel form and develop quantitative models for comparisons with other regions. The Bowers Hollow Creek watershed (3.5 km2) is located within the boundaries of the Forest Service’s Upper Buffalo Wilderness Area. Step-pool morphology varies with the influence of lithology and sediment supply in the Boston Mountains. However, step height and wavelength relationships are generally similar to other regions. Distribution of …


A Tale Of Three Sisters: Reconstructing The Holocene Glacial History And Paleoclimate Record At Three Sisters Volcanoes, Oregon, United States, Shaun Andrew Marcott Jan 2005

A Tale Of Three Sisters: Reconstructing The Holocene Glacial History And Paleoclimate Record At Three Sisters Volcanoes, Oregon, United States, Shaun Andrew Marcott

Dissertations and Theses

At least four glacial stands occurred since 6.5 ka B.P. based on moraines located on the eastern flanks of the Three Sisters Volcanoes and the northern flanks of Broken Top Mountain in the Central Oregon Cascades. The youngest of these advances was the Little Ice Age (LIA) glaciation, which reached its maximum advance 150-200 yrs. B.P. and is defined by the large sharp crested and unvegetated moraines adjacent to the modern glaciers. In isolated locations less than 100 m downslope from these moraines, a second set of sparsely vegetated lateral moraines marks the Late-Neoglacial stand of the glaciers between 2.1 …


Runoff Production In The Upper Rio Chagres Watershed, Panama, Fred Ogden Dec 2004

Runoff Production In The Upper Rio Chagres Watershed, Panama, Fred Ogden

Fred L. Ogden

Runoff production in tropical watersheds is governed by a wide variety of potential sources and there have been few rigorous studies to date. The 414 km2 upper Río Chagres basin offers a unique opportunity to better understand the runoff production mechanisms in tropical watersheds through data analysis and modeling with rainfall and runoff data. Flow data and tipping bucket rain gage data are available at both the basin outlet (Chico gage) and for an 80.6 km2 internal basin location (Piedras gage). Modeling is performed using the Sacramento Soil Moisture Accounting Model (SAC-SMA), calibrated using data from 2000 and verified using …


Storm Deposited Fish Debris In The Cretaceous Mowry Shale Near Vernal, Utah, Alvin Anderson, Bart Kowallis Dec 2004

Storm Deposited Fish Debris In The Cretaceous Mowry Shale Near Vernal, Utah, Alvin Anderson, Bart Kowallis

Bart J Kowallis

Isolated, lens-shaped accumulations of fi sh bones, scales, teeth, and coprolites in a sandy matrix occur along a few bedding planes within the Cretaceous Mowry Shale in an outcrop along Highway 191 north of Vernal, Utah. These accumulations have previously been interpreted to be large coprolites or regurgitate material, but are actually storm lag deposits in a sediment-starved basin. Accumulations (lenses) vary in size: the largest measured is 15 x 10 cm in plan view and 2 cm thick. Matrix in these lenses consist of fine-grained, well-rounded quartz grains that are absent in the surrounding shale layers. The disarticulated fossil …


Refining The Geologic Time Scale: An Integrated Biostratigraphic Approach., Daniel Goldman Dec 2004

Refining The Geologic Time Scale: An Integrated Biostratigraphic Approach., Daniel Goldman

Daniel Goldman

Funding agency: Petroleum Research Fund Amount: $50,000.00 Investigator: Dr. Goldman, S.A. Leslie Year: 2005/3 yrs


Overview Of Radiometric Ages In Three Allochthonous Belts Of Northern Venezuela: Old Ones, New Ones, And Their Impact On Regional Geology, V Sisson, H Lallemant, M Ostos, Ann Blythe, L Snee, P Copeland, J Wright, R Donelick, L Guth Dec 2004

Overview Of Radiometric Ages In Three Allochthonous Belts Of Northern Venezuela: Old Ones, New Ones, And Their Impact On Regional Geology, V Sisson, H Lallemant, M Ostos, Ann Blythe, L Snee, P Copeland, J Wright, R Donelick, L Guth

Ann Blythe

No abstract provided.


Exploring The Persistence Of Sorted Bedforms On The Inner-Shelf Of Wrightsville Beach, North Carolina, Benjamin Gutierez, George Voulgaris, Robert Thieler Dec 2004

Exploring The Persistence Of Sorted Bedforms On The Inner-Shelf Of Wrightsville Beach, North Carolina, Benjamin Gutierez, George Voulgaris, Robert Thieler

George Voulgaris

Geological studies offshore of Wrightsville Beach, North Carolina reveal subtle large-scale regions of coarse sand with gravel and shell hash (widths between 100 and 200 m and negative relief of ∼1 m) that trend obliquely to the coast. It was previously suggested that these regions serve as conduits for sand exchange between the shoreface and inner shelf during storm-associated downwelling. Consequently they were classified as rippled scour depressions. More recently, the role of alongshore flows and self-organization as a result of inhibited settling of fine sand has been discussed. In this study, 45 days of near-bed current measurements were analyzed …


Fracturing In A Reverse Drag Fold, Parashant Canyon, Az, Phillip Resor, Patrick Welsh Dec 2004

Fracturing In A Reverse Drag Fold, Parashant Canyon, Az, Phillip Resor, Patrick Welsh

Phillip G Resor

The western Grand Canyon is a natural laboratory for investigating processes of continental extension due to the great vertical exposure (> 1 km) and the relatively simple pre-extensional structure. We have undertaken a detailed field study of joint frequency in Parashant Canyon, a natural cross-section through the normal fault related Lone Mountain monocline, in order to better understand the role that joints play in accommodating extensional folding. The Lone Mountain monocline is made up of two half-monoclinal flexures: a hanging wall fold in which dips gradually increase toward the fault from a regional dip of 2° to a maximum dip …


Effect Of Channel Bifurcation On Residual Estuarine Circulation: Winyah Bay, South Carolina, Yong Kim, George Voulgaris Dec 2004

Effect Of Channel Bifurcation On Residual Estuarine Circulation: Winyah Bay, South Carolina, Yong Kim, George Voulgaris

George Voulgaris

The residual circulation pattern of Winyah Bay, the fourth largest estuary on the eastern coast of the US, is examined using stationary and shipborne current measurements during periods of low freshwater discharge. The estuary has a complex morphology with a single channel and narrow banks at the river entrance and the bay mouth, and a bifurcated channel system (main and western channels, respectively) in the middle part that appears to affect the residual circulation. Overall, the upper (single channel morphology) and middle (dual-channel morphology) parts of the estuary exhibit a baroclinic residual circulation. The presence of bifurcated channels in the …


Refining The Geologic Time Scale:An Integrated Biostratigraphic Approach, Daniel Goldman Dec 2004

Refining The Geologic Time Scale:An Integrated Biostratigraphic Approach, Daniel Goldman

Daniel Goldman

Funding agency: UDRI Seed Grant Amount: $9,000.00


Sustainable Development And Natural Governance: The Challenges Ahead, John Dernbach, Dan Tarlock Dec 2004

Sustainable Development And Natural Governance: The Challenges Ahead, John Dernbach, Dan Tarlock

John C. Dernbach

No abstract provided.


Targets, Timetables And Effective Implementing Mechanisms: Necessary Building Blocks For Sustainable Development, John C. Dernbach Dec 2004

Targets, Timetables And Effective Implementing Mechanisms: Necessary Building Blocks For Sustainable Development, John C. Dernbach

John C. Dernbach

No abstract provided.


Integrating High-Precision Aftershock Locations And Geodetic Observations To Model Coseismic Deformation Associated With The 1995 Kozani-Grevena Earthquake, Greece, Phillip G. Resor, David Pollard, T J. Wright, G C. Beroza Dec 2004

Integrating High-Precision Aftershock Locations And Geodetic Observations To Model Coseismic Deformation Associated With The 1995 Kozani-Grevena Earthquake, Greece, Phillip G. Resor, David Pollard, T J. Wright, G C. Beroza

Phillip G Resor

We integrate high-precision aftershock locations with geodetic inverse modeling to create a more complete kinematic model for the Kozani-Grevena earthquake sequence. Using the double-difference algorithm, we have improved relative hypocentral locations by a factor of ∼7 and thus imaged the details of the fault network associated with the seismic sequence. The interpreted fault network consists of multiple segments including (1) a master normal fault that strikes nearly due west and dips toward the north at 43°, extending from 6 to 15 km depth; (2) an upper segment that connects the top of the seismicity to the observed surface ruptures and …


Inverting For Slip On Three-Dimensional Fault Surfaces Using Angular Dislocations, Phillip G. Resor, David Pollard, Frantz Maerten, Laurent Maerten Dec 2004

Inverting For Slip On Three-Dimensional Fault Surfaces Using Angular Dislocations, Phillip G. Resor, David Pollard, Frantz Maerten, Laurent Maerten

Phillip G Resor

The increasing quality of geodetic data (synthetic aperture radar interferometry [INSAR] dense Global Positioning System [GPS] arrays) now available to geophysicists and geologists are not fully exploited in slip-inversion procedures. Most common methods of inversion use rectangular dislocation segments to model fault ruptures and therefore oversimplify fault geometries. These geometric simplifications can lead to inconsistencies when inverting for slip on earthquake faults, and they preclude a more complete understanding of the role of fault geometry in the earthquake process. We have developed a new three-dimensional slip-inversion method based on the analytical solution for an angular dislocation in a linear-elastic, homogeneous, …


Hartford Basin Cross Section – Southington To Portland, Ct, Phillip G. Resor, J Z. Deboer Dec 2004

Hartford Basin Cross Section – Southington To Portland, Ct, Phillip G. Resor, J Z. Deboer

Phillip G Resor

No abstract provided.


Laramie Peak Shear System, Central Laramie Mountains, Wyoming, Usa: Regeneration Of The Archean Wyoming Province During Palaeoproterozoic Accretion, Phillip G. Resor, Arthur W. Snoke Dec 2004

Laramie Peak Shear System, Central Laramie Mountains, Wyoming, Usa: Regeneration Of The Archean Wyoming Province During Palaeoproterozoic Accretion, Phillip G. Resor, Arthur W. Snoke

Phillip G Resor

The Laramie Peak shear system (LPSS) is a 10 km-thick zone of heterogeneous general shear (non-coaxial) that records significant tectonic regeneration of middle-lower crustal rocks of the Archean Wyoming province. The shear system is related to the 1.78–1.74 Ga Medicine Bow orogeny that involved the collision of an oceanic-arc terrane (Colorado province or Green Mountain block or arc) with the rifted, southern margin of the Wyoming province. The style and character of deformation associated with the LPSS is distinctive: a strong, penetrative (mylonitic) foliation commonly containing a moderately steep, SW-plunging elongation lineation. In mylonitic quartzo-feldspathic gneisses of the Fletcher Park …


Western End Of The Honey Hill Fault Along The Eastern Bank Of The Connecticut River, Phillip G. Resor, J Z. Deboer Dec 2004

Western End Of The Honey Hill Fault Along The Eastern Bank Of The Connecticut River, Phillip G. Resor, J Z. Deboer

Phillip G Resor

No abstract provided.


Influence Of Hydraulic Property Correlation On Predicted Dense Nonaqueous Phase Liquid Source Zone Architecture, Mass Recovery And Contaminant Flux, Lawrence D. Lemke, Linda M. Abriola, John R. Lang Dec 2004

Influence Of Hydraulic Property Correlation On Predicted Dense Nonaqueous Phase Liquid Source Zone Architecture, Mass Recovery And Contaminant Flux, Lawrence D. Lemke, Linda M. Abriola, John R. Lang

Environmental Science and Geology Faculty Research Publications

Organic liquid saturation distributions resulting from a simulated tetrachloroethene (PCE) spill were generated with alternative models of spatially varying aquifer properties for a statistically homogeneous, nonuniform sand aquifer. The distributions were analyzed to quantify DNAPL source zone characteristics and then incorporated as initial conditions for simulated PCE recovery using surfactant-enhanced aquifer remediation (SEAR). The predicted evolution of the spatial distribution of DNAPL saturations or source zone ‘‘architectures’’ and associated remediation efficiencies are strongly influenced by the spatial correlation of aquifer parameters and multiphase flow constitutive relationships. Model predictions suggest that removal of 60 to 99% of entrapped PCE can reduce …


Barotropic Tides In The South Atlantic Bight, Brian O. Blanton, Francisco E. Werner, Harvey E. Seim, Richard A. Luettich Jr., Daniel R. Lynch, Keston W. Smith, George Voulgaris, Frederick M. Bingham, Francis Way Dec 2004

Barotropic Tides In The South Atlantic Bight, Brian O. Blanton, Francisco E. Werner, Harvey E. Seim, Richard A. Luettich Jr., Daniel R. Lynch, Keston W. Smith, George Voulgaris, Frederick M. Bingham, Francis Way

George Voulgaris

The characteristics of the principal barotropic diurnal and semidiurnal tides are examined for the South Atlantic Bight (SAB) of the eastern United States coast. We combine recent observations from pressure gauges and ADCPs on fixed platforms and additional short-term deployments off the Georgia and South Carolina coasts together with National Ocean Service coastal tidal elevation harmonics. These data have shed light on the regional tidal propagation, particularly off the Georgia/South Carolina coast, which is perforated by a dense estuary/tidal inlet complex (ETIC). We have computed tidal solutions for the western North Atlantic Ocean on two model domains. One includes a …


Timing And Nature Of The Deepening Of The Tasmanian Gateway, Catherine E. Stickley, Henk Brinkhuis, Stephen A. Schellenberg, Appy Sluijs, Ursula Röhl, Michael Fuller, Marianne Grauert, Matthew Huber, Jeroen Warnaar, Graham L. Williams Dec 2004

Timing And Nature Of The Deepening Of The Tasmanian Gateway, Catherine E. Stickley, Henk Brinkhuis, Stephen A. Schellenberg, Appy Sluijs, Ursula Röhl, Michael Fuller, Marianne Grauert, Matthew Huber, Jeroen Warnaar, Graham L. Williams

Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications

Tectonic changes that produced a deep Tasmanian Gateway between Australia and Antarctica are widely invoked as the major mechanism for Antarctic cryosphere growth and Antarctic Circumpolar Current (ACC) development during the Eocene/Oligocene (E/O) transition (∼34–33 Ma). Ocean Drilling Program (ODP) Leg 189 recovered near-continuous marine sedimentary records across the E/O transition interval at four sites around Tasmania. These records are largely barren of calcareous microfossils but contain a rich record of siliceous- and organic-walled marine microfossils. In this study we integrate micropaleontological, sedimentological, geochemical, and paleomagnetic data from Site 1172 (East Tasman Plateau) to identify four distinct phases (A–D) in …