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Basal Mechanics Of Ice Streams: Insights From The Stick-Slip Motion Of Whillans Ice Stream, West Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Robert A. Bindschadler, Matt A. King Feb 2009

Basal Mechanics Of Ice Streams: Insights From The Stick-Slip Motion Of Whillans Ice Stream, West Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley, Robert A. Bindschadler, Matt A. King

All Faculty Scholarship for the College of the Sciences

The downstream portion of Whillans Ice Stream, West Antarctica, moves primarily by stick-slip motion. The observation of stick-slip motion suggests that the bed is governed by velocity-weakening physics and that the basal physics is more unstable than suggested by laboratory studies. The stick-slip cycle of Whillans Ice Plain exhibits substantial variability in both the duration of sticky periods and in slip magnitude. To understand this variability, we modeled the forces acting on the ice stream during the stick phase of the stick-slip cycle. The ocean tides introduce changes in the rate at which stress is applied to the ice plain. …


Overland Flow And Rainfall Simulation Studies On Ornamental Vegetation, Compost, And Jute Netting, Brent G. Hallock, Candace Kimmelshue, Steve Rein, Michael Curto, Misty Scharff Feb 2009

Overland Flow And Rainfall Simulation Studies On Ornamental Vegetation, Compost, And Jute Netting, Brent G. Hallock, Candace Kimmelshue, Steve Rein, Michael Curto, Misty Scharff

Earth and Soil Sciences

The literature is replete with studies quantifying erosion control effectiveness from raindrop impact on various vegetation types and erosion control products. However, there is little published overland flow research documenting the effectiveness of ornamental vegetation and erosion control products in filtering sediment and nutrients from stormwater runoff. The California Department of Transportation and the Office of Water Programs, California State University, Sacramento, has conducted two studies at the Erosion Control Research Facility at Cal Poly State University, San Luis Obispo addressing the use of ornamental vegetation as an erosion control treatment. The first study addressed how well ornamental vegetation, jute …


Tree Canopy Types Constrain Plant Distributions In Ponderosa Pine- Gambel Oak Forests, Northern Arizona, Scott R. Abella Feb 2009

Tree Canopy Types Constrain Plant Distributions In Ponderosa Pine- Gambel Oak Forests, Northern Arizona, Scott R. Abella

Public Policy and Leadership Faculty Research

Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa pine-Gambel oak (Quercus gambelii) forests to measure the influences of tree canopy types on understory plant communities and soil properties. On ten 2.5-acre (1-ha) sites, I sampled five 43-ft2 (4-m2) plots below each of the following five canopy types: openings; single ponderosa pine; and Gambel oak single stems, dispersed clumps, and thickets. …


Changes In Water Levels And Storage In The High Plains Aquifer, Predevelopment To 2007, V. L. Mcguire Feb 2009

Changes In Water Levels And Storage In The High Plains Aquifer, Predevelopment To 2007, V. L. Mcguire

United States Geological Survey: Publications

The High Plains aquifer underlies 111.6 mil¬lion acres (174,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The area overlying the High Plains aquifer is one of the primary agricultural regions in the Nation. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial irrigation with ground water in the aquifer area. By 1980, water levels in the High Plains aquifer in parts of Texas, Oklahoma, and southwestern Kansas had declined more than 100 feet (Luckey and others, 1981). In response to these water-level declines, …


Louisiana Barrier Island Comprehensive Monitoring Program (Bicm) Volume 3: Bathymetry And Historical Seafloor Change 1869-2007 Part 2: South Central Louisiana And Northern Chandeleur Islands, Bathymetry Maps, Michael Miner, Mark Kulp, Jeffrey P. Motti, Dallon Weathers, Phil Mccarty, Michael Brown, Julie Torres, Luis Martinez, James G. Flocks, Nancy Dewitt, Nick Ferina, B J. Reynolds, David Twichell, Wayne Baldwin, Bill Danforth, Chuck Worley, Emile Bergeron Feb 2009

Louisiana Barrier Island Comprehensive Monitoring Program (Bicm) Volume 3: Bathymetry And Historical Seafloor Change 1869-2007 Part 2: South Central Louisiana And Northern Chandeleur Islands, Bathymetry Maps, Michael Miner, Mark Kulp, Jeffrey P. Motti, Dallon Weathers, Phil Mccarty, Michael Brown, Julie Torres, Luis Martinez, James G. Flocks, Nancy Dewitt, Nick Ferina, B J. Reynolds, David Twichell, Wayne Baldwin, Bill Danforth, Chuck Worley, Emile Bergeron

Pontchartrain Institute Reports and Studies

No abstract provided.


Spokane River In Idaho And Washington Tmdl Water Quality And Hydrodynamic Modeling Quality Assurance Project Plan -- Draft, Scott A. Wells, Chris Berger Feb 2009

Spokane River In Idaho And Washington Tmdl Water Quality And Hydrodynamic Modeling Quality Assurance Project Plan -- Draft, Scott A. Wells, Chris Berger

Civil and Environmental Engineering Faculty Publications and Presentations

The focus of this present study is to perform the following tasks:

• Converting the Upper Spokane River CE‐QUAL‐W2 models (Washington and Idaho) to version 3.6

• Combining the Washington and Idaho models

• Reviewing and updating model boundary conditions

• Check model calibration

• Meet with stakeholders

• Develop and Run Modeling Scenarios

• Create reports on calibration and scenario runs


Evolution And Stratigraphic Architecture Of Marine Slope Gully Complexes: Monterey Formation (Miocene), Gaviota Beach, California, Kathleen D. Surpless, R. B. Ward, S. A. Graham Feb 2009

Evolution And Stratigraphic Architecture Of Marine Slope Gully Complexes: Monterey Formation (Miocene), Gaviota Beach, California, Kathleen D. Surpless, R. B. Ward, S. A. Graham

Earth and Environmental Geosciences Faculty Research

Three small headlands in the sea cliffs west of Gaviota Beach, California, are the remnant fill of three discrete submarine gullies incised into the late Miocene submarine slope environment. These promontories provide excellent, three-dimensional exposure of the gully fill in outcrop, permitting documentation of their complex internal stratigraphic architecture. Detailed study of these exposures elucidates the sedimentologic processes that occur in the filling of slope gullies, guides interpretation of the acoustic records of otherwise unsampled modern gully systems on continental slopes, and provides insight into the heterogeneity that may characterize slope gully petroleum reservoirs.

We develop a comprehensive facies scheme …


Effect Of Bacterial Adsorption On Low Frequency Electrical Properties Of Clean Quartz Sands And Iron-Oxide Coated Sands, Gamal Z. Abdel Aal, Estella A. Atekwana, Sylvia Radzikowski, Silvia Rossbach Feb 2009

Effect Of Bacterial Adsorption On Low Frequency Electrical Properties Of Clean Quartz Sands And Iron-Oxide Coated Sands, Gamal Z. Abdel Aal, Estella A. Atekwana, Sylvia Radzikowski, Silvia Rossbach

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Low frequency electrical measurements (0.1-1000 Hz) were conducted to investigate the adsorption effect of Pseudomonas aeruginosa cells onto clean quartz sands and iron-oxide coated sands. The clean quartz sands showed a gradual increase in the microbial adsorption to mineral grains, concurrent with an increase of 13% in the imaginary conductivity component (σ″). However, iron-oxide coated sands (20-100% by weight) showed a rapid increase in microbial adsorption with σ″ reaching a maximum of 37% for the 80-100% iron coated sands. No significant changes were observed in the real conductivity component (σ′) due to microbial adsorption. A power law dependency was observed …


Significant Seismic Anisotropy Beneath The Southern Lhasa Terrane, Tibetan Plateau, Stephen S. Gao, Kelly H. Liu Feb 2009

Significant Seismic Anisotropy Beneath The Southern Lhasa Terrane, Tibetan Plateau, Stephen S. Gao, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Shear wave splitting measurements using teleseismic PKS, SKKS, and SKS phases recorded by station LSA on the southern part of the Lhasa Terrane of the Tibetan Plateau reveal significant azimuthal anisotropy with a splitting time of up to 1.5 s, a conclusion that is contradictory to previous studies which suggested isotropy or weak anisotropy. In addition, systematic variations of the splitting parameters (fast polarization direction and splitting time) with the arriving azimuth of the seismic ray path are observed, suggesting a model of anisotropy that is more complicated than a single layer with horizontal axis of symmetry. The measurements are …


Exhumation Of The Inyo Mountains, California: Implications For The Timing Of Extension Along The Western Boundary Of The Basin And Range Province And Distribution Of Dextral Fault Slip Rates Across The Eastern California Shear Zone, Jeffrey Lee, Daniel F. Stockli, Lewis A. Owen, Robert C. Finkel, Roman Kislitsyn Jan 2009

Exhumation Of The Inyo Mountains, California: Implications For The Timing Of Extension Along The Western Boundary Of The Basin And Range Province And Distribution Of Dextral Fault Slip Rates Across The Eastern California Shear Zone, Jeffrey Lee, Daniel F. Stockli, Lewis A. Owen, Robert C. Finkel, Roman Kislitsyn

All Faculty Scholarship for the College of the Sciences

New geologic mapping, tectonic geomorphologic, 10Be terrestrial cosmogenic nuclide, and (U-Th)/He zircon and apatite thermochronometric data provide the first numerical constraints on late Cretaceous to late Quaternary exhumation of the Inyo Mountains and vertical slip and horizontal extension rates across the eastern Inyo fault zone, California. The east-dipping eastern Inyo fault zone bounds the eastern flank of the Inyo Mountains, a prominent geomorphic feature within the western Basin and Range Province and eastern California shear zone. (U-Th)/He zircon and apatite thermochronometry yield age patterns across the range that are interpreted as indicating: (1) two episodes of moderate to rapid …


Paleomagnetic Behavior Of Volcanic Rocks From Isla Socorro, Mexico, Elise Sbarbori, Lisa Tauxe, Avto Goguitchaichvili, Jaime Urrutia-Fucugauchi, Wendy A. Bohrson Jan 2009

Paleomagnetic Behavior Of Volcanic Rocks From Isla Socorro, Mexico, Elise Sbarbori, Lisa Tauxe, Avto Goguitchaichvili, Jaime Urrutia-Fucugauchi, Wendy A. Bohrson

All Faculty Scholarship for the College of the Sciences

The direction and magnitude of the geomagnetic field vary both spatially and temporally and undergo significant departures from that of a geocentric axial dipole. In order to properly characterize persistent behaviors, time-averaged field models must be based on the highest quality data. Here we present full-vector paleomagnetic data for volcanic units exposed in the southeast quadrant of the island of Socorro, Mexico. We carried out a joint expedition between the Scripps Institution of Oceanography and the Universidad Nacional Autónoma México to Isla Socorro in January of 2005 during which we collected oriented paleomagnetic samples from 21 sites, representing as many …


Phenomena Induced By Powerful Hf Pumping Towards Magnetic Zenith With A Frequency Near The F-Region Critical Frequency And The Third Electron Gyro Harmonic Frequency, N. F. Blagoveshchenskaya, Herbert C. Carlson, V. A. Kornienko, T. D. Borisova, M. T. Rietveld, T. K. Yeoman, A. Brekke Jan 2009

Phenomena Induced By Powerful Hf Pumping Towards Magnetic Zenith With A Frequency Near The F-Region Critical Frequency And The Third Electron Gyro Harmonic Frequency, N. F. Blagoveshchenskaya, Herbert C. Carlson, V. A. Kornienko, T. D. Borisova, M. T. Rietveld, T. K. Yeoman, A. Brekke

Faculty publications

Multi-instrument observational data from an experiment on 13 October 2006 at the EISCAT/HEATING facility at Tromsø, Norway are analysed. The experiment was carried out in the evening hours when the electron density in the F-region dropped, and the HF pump frequency fH was near and then above the critical frequency of the F2 layer. The distinctive feature of this experiment is that the pump frequency was just below the third electron gyro harmonic frequency, while both the HF pump beam and UHF radar beam were directed towards the magnetic zenith (MZ). The HF pump-induced phenomena were diagnosed with several instruments: …


Predicting The Geodetic Signature Of Mw 8 Slow Slip Events, Brendan J. Meade, John P. Loveless Jan 2009

Predicting The Geodetic Signature Of Mw 8 Slow Slip Events, Brendan J. Meade, John P. Loveless

Geosciences: Faculty Publications

Elastic dislocation models of geodetic measurements

above subduction zones have led to the identification of

MW 6.0– 7.2 slow slip events (SSEs) that release elastic

strain over periods of days to months, but great (MW 8)

SSEs have remained unidentified. We extrapolate

observations of SSE duration and slip magnitude to show

that slip velocity decreases with event magnitude and

predict that the slip velocity of MW 8 SSEs is 50 mm/yr.

The slip velocity for great SSEs may never exceed the

plate convergence rate and thus never produce a reversal

in trench perpendicular motion. Instead, geodetically

constrained estimates of apparent …


Surface Cracks Record Long-Term Seismic Segmentation Of The Andean Margin, John P. Loveless, Richard W. Allmendinger, Matthew E. Pritchard, Jordan L. Garroway, Gabriel González Jan 2009

Surface Cracks Record Long-Term Seismic Segmentation Of The Andean Margin, John P. Loveless, Richard W. Allmendinger, Matthew E. Pritchard, Jordan L. Garroway, Gabriel González

Geosciences: Faculty Publications

Understanding the long-term patterns of great earthquake rupture along a subduction zone provides a framework for assessing modern seismic hazard. However, evidence that can be used to infer the size and location of past earthquakes is typically erased by erosion after a few thousand years. Meter-scale cracks that cut the surface of coastal areas in northern Chile and southern Peru preserve a record of earthquakes spanning several hundred thousand years owing to the hyperarid climate of the region. These cracks have been observed to form during and/or shortly after strong subduction earthquakes, are preserved for long time periods throughout the …


Lophorhothon., David R. Schwimmer Jan 2009

Lophorhothon., David R. Schwimmer

Faculty Bibliography

No abstract provided.


Soil Ph In Northern And Southern Areas Of The Wa Wheatbelt, Chris Gazey, Joel Andrew Jan 2009

Soil Ph In Northern And Southern Areas Of The Wa Wheatbelt, Chris Gazey, Joel Andrew

Bulletins 4000 -

More than 80% of the topsoils sampled fall below the critical surface pHCaCl2 of 5.5 in the northern and southern wheatbelt study areas, with more in the south than the north. These results confirm soil acidity is a serious concern throughout the WA wheatbelt when considered in conjunction with the more intensive analysis of current soil pH throughout the Avon River Basin (2005–2008).

With low topsoil pH, it is likely that subsurface acidity is also a problem. For soil acidity to be managed, subsurface pH also needs to be known. In the Avon River Basin study, about half of the …


Survey Of Western Australian Agricultural Lime Sources, Chris Gazey, Dave Gartner Jan 2009

Survey Of Western Australian Agricultural Lime Sources, Chris Gazey, Dave Gartner

Bulletins 4000 -

As a service to WA wheatbelt farmers, to assist with cost effective management of soil acidity, a survey of agricultural lime availability and quality was conducted by the Department of Agriculture and Food, Western Australia.

The quality of agricultural lime surveyed varied widely between pits. High quality lime is available from limes and, limestone and dolomite sources. Twice as much of the lowest neutralising value lime surveyed would need to be applied compared to the highest to achieve the same increase in soil pH. Limes also varied in the distribution of particle sizes. Selecting limes with a high proportion of …


Eogenetic Karst Of The Carbonate Islands Of The Northern Marianas [Abstract], Kevin W. Stafford, John W. Jenson, John E. Mylroie Jan 2009

Eogenetic Karst Of The Carbonate Islands Of The Northern Marianas [Abstract], Kevin W. Stafford, John W. Jenson, John E. Mylroie

Faculty Presentations

No abstract provided.


Ascending Water Of The Delaware Basin, Southeastern New Mexico, And Far West Texas [Abstract], Kevin W. Stafford, Raymond Nance Jan 2009

Ascending Water Of The Delaware Basin, Southeastern New Mexico, And Far West Texas [Abstract], Kevin W. Stafford, Raymond Nance

Faculty Presentations

No abstract provided.


Creating Lakes From Open Pit Mines: Processes And Considerations, Emphasis On Northern Environments, Christopher H. Gammons, Les N. Harris, James M. Castro, Peter A. Cott, Bruce W. Hanna Jan 2009

Creating Lakes From Open Pit Mines: Processes And Considerations, Emphasis On Northern Environments, Christopher H. Gammons, Les N. Harris, James M. Castro, Peter A. Cott, Bruce W. Hanna

Geological Engineering

Creating Lakes from Open Pit Mines: Processes and Considerations, Emphasis on Northern Environments. This document summarizes the literature of mining pit lakes (through 2007), with a particular focus on issues that are likely to be of special relevance to the creation and management of pit lakes in northern climates. Pit lakes are simply waterbodies formed by filling the open pit left upon the completion of mining operations with water. Like natural lakes, mining pit lakes display a huge diversity in each of these subject areas. However, pit lakes are young and therefore are typically in a non-equilibrium state with respect …


Artifact Preservation, Thomas Dolan Jan 2009

Artifact Preservation, Thomas Dolan

Faculty Bibliography

No abstract provided.


Modeled Red Spruce Distribution Response To Climatic Change In Monongahela National Forest, James Michael Stanton Jan 2009

Modeled Red Spruce Distribution Response To Climatic Change In Monongahela National Forest, James Michael Stanton

Theses, Dissertations and Capstones

In Monongahela National Forest of West Virginia, red spruce grows in high-elevation island ecosystems that are particularly sensitive to changes in climatic conditions. The ecological niche modeling application Maxent was used to project the distribution response of red spruce to climatic change for the purposes of conservation planning. Red spruce distribution data was acquired from the United States Forest Service. Three sets of nineteen bioclimatic variables, corresponding to present, 2050, and 2080 conditions, were derived from 1961-1990 monthly temperature and precipitation means and the IPCC A2 emissions scenario of HadCM3. The modeling revealed rapidly diminishing red spruce habitat suitability from …


Oxygen And Hydrogen Isotope Fractionation In Serpentine–Water And Talc–Water Systems From 250 To 450°C Mpa, Peter Saccocia, J. S. Seewald, W. C. Shanks Iii Jan 2009

Oxygen And Hydrogen Isotope Fractionation In Serpentine–Water And Talc–Water Systems From 250 To 450°C Mpa, Peter Saccocia, J. S. Seewald, W. C. Shanks Iii

Geological Sciences Faculty Publications

Oxygen and hydrogen isotope fractionation factors in the talc–water and serpentine–water systems have been determined by laboratory experiment from 250 to 450 °C at 50 MPa using the partial exchange technique. Talc was synthesized from brucite + quartz, resulting in nearly 100% exchange during reaction at 350 and 450 °C. For serpentine, D–H exchange was much more rapid than 18O–16O exchange when natural chrysotile fibers were employed in the initial charge. In experiments with lizardite as the starting charge, recrystallization to chrysotile enhanced the rate of 18O–16O exchange with the coexisting aqueous phase. Oxygen …


Ordway Weather And Water Data 2009, Macalester College Jan 2009

Ordway Weather And Water Data 2009, Macalester College

Ordway Weather Data

Contains daily readings for the year indicated. The values include: PAR umol/s/m2, avg wind dir degree, avg windspeed mph, Avg Max Windspeed mph, Avg airtemp C, Avg RH %, Avg BP mmHg, Avg DailyRain in, Avg Rain Duration sec, Avg RainIntensity in/h, Avg Water Temp F, Avg sp cond mS/cm, avg pH, Avg Turb NTU+, Avg ODOSat %, Avg ODO mg/L, Water station PAR umol/s/m2, Avg Water Level m. File format: CSV.


Preserving Assets In At-Risk Municipalities: Financial Strategies For Climate Change Adaptation, New England Environmental Finance Center Jan 2009

Preserving Assets In At-Risk Municipalities: Financial Strategies For Climate Change Adaptation, New England Environmental Finance Center

Climate Change

A large share of America's population, businesses and economic activity now occurs in coastal areas. At the same time, during this century many coastal communities are likely to be severely impacted by sea level rise and increased storm surge and tidal flooding.

“What to do” about this vulnerability is the subject of this brief. It is intended to help municipalities identify courses of action and steps they might take toward increasing their resilience, especially regarding financial resources that will need to be allocated toward the various strategies identified.


Detecting Source Regions Of Wave Activities In The Tropical Atmosphere By Applying Beamforming To Interpolated Data Grids, Q. Steven Hu, Zhaoning Liang Jan 2009

Detecting Source Regions Of Wave Activities In The Tropical Atmosphere By Applying Beamforming To Interpolated Data Grids, Q. Steven Hu, Zhaoning Liang

Department of Earth and Atmospheric Sciences: Faculty Publications

Wave activities are primary sources of weather disturbances and cyclones in the tropical atmosphere. One such activity is the intraseasonal variations in wind, convection, and precipitation in the tropical Indian and western tropical Pacific region. These variations affect the intensity, break and reset, and rainfall in the Indian and the East Asian monsoons. Detecting the source regions of these wave activities is essential for understanding and for prediction of wave development. In this study, a fixed beamforming method is proposed to deduce source regions of some wave activities in the tropical atmosphere. This method is tested with simulations of single …


Experimental Evidence Of Non-Linear Dissipation Using Acoustic Micro-Lapses, G. Quiroga-Goode, K. Van Wijk Jan 2009

Experimental Evidence Of Non-Linear Dissipation Using Acoustic Micro-Lapses, G. Quiroga-Goode, K. Van Wijk

Geosciences Faculty Publications and Presentations

Non-linear material behaviour is observed experimentally in a laboratory using a new method called Acoustic Micro-Lapses (AML). In this approach, the shooting of two waves is synchronised in a way that the second wave (TW) is to sense the fluctuations in material stiffness induced by the first (PW). The tests include four samples; twenty trials are performed for each sample by increasing time-delays between the waves. The recorded waves are decoupled and compared to determine spectral differences by computing a quantity proportional to the energy difference as function of the increasing time delay (). For a tight sandstone and aluminium …


Nutrient Analysis Of The Estuarine And River Waters Of The Santa Margarita River Estuary, Barbara Elisabeth Long Jan 2009

Nutrient Analysis Of The Estuarine And River Waters Of The Santa Margarita River Estuary, Barbara Elisabeth Long

Theses Digitization Project

The purpose of this project was to analyze nutrient concentrations in the estuarine and river waters of the Santa Margarita River Estuary located on United States Marine Corps Base, Camp Pendleton in northern San Diego County, north of Oceanside, California.


In Situ Bioremediation Of Perchlorate In Soil And Groundwater, David Christopher Bertolacci Jan 2009

In Situ Bioremediation Of Perchlorate In Soil And Groundwater, David Christopher Bertolacci

Theses Digitization Project

This project conducted a technology assessment for in-situ bioremediation of perchlorate in soil and groundwater and assessed the suitability of electon donor amendments.


Cyanide Analysis In Wastewater, Heather Marie Lutes Jan 2009

Cyanide Analysis In Wastewater, Heather Marie Lutes

Theses Digitization Project

The purpose of this project was to look at and determine the methods that would best prevent the occurrence of false readings durring testing and analysis of cyanide in wastewater. This project was designed to help those wastewater treatment plants in the Santa Ana Watershed who are in the process of developing a uniform method that minimizes or eliminates interferences currently found. Eastern Municipal District, Inland Empire Utilities agency, Orange County Water District, San Bernardino Valley Municipal, Water District, and Western Municipal Water District all are members of the Santa Ana Watershed Project Authority (SAWPA).