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Full-Text Articles in Physical Sciences and Mathematics

Geochemistry And Geochronology Of The Central Metasedimentary Belt Boundary Thrust Zone Thrust Sheets In Southern Ontario, Grenville Province, Kenjo Agustsson Nov 2012

Geochemistry And Geochronology Of The Central Metasedimentary Belt Boundary Thrust Zone Thrust Sheets In Southern Ontario, Grenville Province, Kenjo Agustsson

Natural Resources Management and Environmental Sciences

Studies of pre-Grenvillian (1.4–1.3 Ga) plutons offer insight into the dynamics of arc amalgamation and backarc rifting prior to continental collision in the Ottawan orogeny. The Central Metasedimentary Belt boundary thrust zone (CMBbtz) is a northeast–southwest trending thrust zone consisting of metaplutonic thrust sheets enveloped in gneissic tectonites and calcitic– dolomitic marbles. Tonalitic CMBbtz thrust sheets (Dysart and Redstone) are made up of upper amphibolite-facies, foliation-concordant metatonalites (+ amphibole ± biotite ± accessory zircon and titanite) and amphibolites (± biotite ± clinopyroxene), and are located in the southern Ontario Grenville Province. These thrust sheets are thought to have formed and …


Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank Aug 2012

Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank

STAR Program Research Presentations

Jupiter’s satellite Europa, whose surface is composed of ice with a possible water ocean beneath, could conceivably serve as an abode for extraterrestrial life. This and other icy celestial bodies may contain organic macromolecular solid material that is produced when surface ices are exposed to ultraviolet radiation and/or electrical energy. Tidal and tectonic stresses or meteorite impacts in icy crusts may produce electrical discharges, which would provide the energy for in-situ synthesis of the organic solids. This electrical energy can be provided by positive hole charge carrier activation. Positive holes exhibit properties such as the ability to flow out of …


Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett Aug 2012

Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett

STAR Program Research Presentations

Hydrogen is an attractive energy option because of its low
environmental impact, but a critical problem is its low energy
density, which makes it difficult to store. For example, the US
Department of Energy (DOE) hydrogen plan for fuel cell powered
vehicles requires a gravimetric density of 6.5 wt%. There are several
existing hydrogen storage methods, including compressed gas,
liquefaction, metal hydrides, and physisorption, but at present, none
of these technologies comes close to achieving the targets set by the
DOE. Although chemical storage methods have been claimed to be the
most promising hydrogen storage technology, and activated carbons the …


Raman Mapping Of Mars Relevant Minerals Using Multiple Excitation Wavelenghts, Victoria Campbell, William Abbey Aug 2012

Raman Mapping Of Mars Relevant Minerals Using Multiple Excitation Wavelenghts, Victoria Campbell, William Abbey

STAR Program Research Presentations

The purpose of this project is to map Mars relevant minerals using the Raman instrument Horiba LabRam Raman. The Raman spectrometer is a non-invasive sampling technique used to identify mineral composition of various compositions by measuring the “Raman Shift” of each mineral. This was accomplished by using a green (532nm) laser which acted as a monochromatic light source. This source was absorbed by the sample and reemitted. The frequency of the reemitted photons are then shifted up or down in comparison with original frequency, which is referred to as the ‘Raman Effect’. The samples with shorter wavelengths produced a stronger …


Exploration Of Charge Carriers In Obsidian, Ryan Nordvik, Friedemann Freund Aug 2012

Exploration Of Charge Carriers In Obsidian, Ryan Nordvik, Friedemann Freund

STAR Program Research Presentations

This research effort is part of an ongoing investigation into stress-activated positive hole charge carriers in common igneous and high-grade metamorphic rocks. The findings have already revealed potential early earthquake detection mechanisms and caused a re-think on the processes that could conceivably contribute to the formation of and evolution of life. Positive holes are defect electrons in the oxygen anion sub-lattice of silicate minerals that have demonstrated some intriguing capabilities: flowing out of a stressed rock volume; causing oxidation reactions at the rock-water interface and ionization at the rock-air interface; and traveling great distances. This research seeks to determine if …


Leds And Astronomy, Britny N. Delp, Stephen M. Pompea Aug 2012

Leds And Astronomy, Britny N. Delp, Stephen M. Pompea

STAR Program Research Presentations

Using a Czerny-Turner spectrometer, 45 different types of outdoor lights were categorized. These spectra were used to determine how useful the light is to human eyes and how dark skies friendly these lights are. Dark skies friendly lighting means that little to no light shines above a right angle to the light, and should emit as little as possible below 500nm (green) wavelengths. The short wavelengths present a problem to astronomers in the form of Rayleigh scattering. The following criterion were used in selecting the best source for urban and rural lighting: color rendition measured by color rendering index (CRI), …


Stratigraphy Of Quaternary Dunes By Sand Mineralogy And Pedogenic Features, Los Osos, California, Lyssa A. Cousineau Jul 2012

Stratigraphy Of Quaternary Dunes By Sand Mineralogy And Pedogenic Features, Los Osos, California, Lyssa A. Cousineau

Master's Theses

The goal of this study was to assess mineralogy and pedogenic features of sand dunes in a stratigraphic sequence. The purpose was to determine whether these features significantly differ to reflect age differences with depth within the sequence. This study was conducted in Montaña de Oro State Park, located on the central Californian coast eighteen kilometers northwest of San Luis Obispo in San Luis Obispo County.

Samples were collected from the vertical exposure of one dune face by stratified random sampling at 1.0-m vertical intervals. Particle size distribution was determined through particle-size analysis by hydrometer and sieve. Electrical conductivity and …


The Spatial Distribution Of K-Factor Values Across A Toposequence And A Soil Survey Map Unit, Jacqueline Elizabeth Tilligkeit Jul 2012

The Spatial Distribution Of K-Factor Values Across A Toposequence And A Soil Survey Map Unit, Jacqueline Elizabeth Tilligkeit

Master's Theses

Rivers and streams are adversely affected by an increase in sedimentation in their waters from eroding land. High sediment loads in streams can bury fish eggs and prevent hatching, increasing nutrients in the water causing algae blooms, or even contaminating the water with heavy metals carried in or on the aggregates. The erodibility of soil is valuable knowledge to all land users so that we may predict soil loss and its potential to pollute streams. This is done by using the Revised Universal Soil Loss Equation (RUSLE). By predicting soil loss from a given landscape, land managers can take mitigation …


Determining Ancient Movement Of The Sur–Nacimiento Fault Zone Using Detrital Zircon Geochronology, Jennifer Per Lee Jun 2012

Determining Ancient Movement Of The Sur–Nacimiento Fault Zone Using Detrital Zircon Geochronology, Jennifer Per Lee

Natural Resources Management and Environmental Sciences

Middle Cretaceous movement along the Sur–Nacimiento Fault has implications for our understanding of how convergent tectonic margins evolve and for the architecture of forearc basins. Traditional explanations suggest an autochthonous California Mesozoic Forearc that underwent sinistral or thrust displacement; although recent research suggests either an allochthonous forearc or an isolated Nacimiento Block that experienced significant dextral displacement. Detrital zircons obtained from the Great Valley Group within the Nacimiento block provide age distribution patterns that can help identify sources of sediment deposition and therefore the past location of the Nacimiento block. Using U-Pb detrital zircon geochronology, we have discovered a dominance …


The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider Jun 2012

The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider

Natural Resources Management and Environmental Sciences

Changes in land use and land management practices are regarded as one of the main factors in altering the hydrogeological system, causing changes in runoff, surface supply yields, and the quality of receiving water (Tong and Chen, 2002). Phosphorus is a significant contributor to accelerated eutrophication of fresh water and is largely sourced from agricultural runoff (Sharpley et al., 1994). The dominant processes controlling solution composition in agricultural soils are primarily ‘chemical’ for P (i.e. adsorption/desorption and dissolution/precipitation) (Edwards and Withers, 1998). Biochar has chemical characteristics that have the potential to adsorb P or influence precipitation of P insoluble pools …


A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson Jun 2012

A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson

Natural Resources Management and Environmental Sciences

No abstract provided.


Factors Influencing Landslides In The Bittercreek Wildlife Refuge, David Mceachern Jun 2012

Factors Influencing Landslides In The Bittercreek Wildlife Refuge, David Mceachern

Natural Resources Management and Environmental Sciences

No abstract provided.


A Discussion Of Factors Involved In The Formation Of Slab Avalanches And An Analysis Of Avalanche Risk In The Sierra Nevada Mountains Using Gis, Kevin C. Howen Jun 2012

A Discussion Of Factors Involved In The Formation Of Slab Avalanches And An Analysis Of Avalanche Risk In The Sierra Nevada Mountains Using Gis, Kevin C. Howen

Natural Resources Management and Environmental Sciences

As winter recreational activities increase in mountainous environments, the need for a better understanding of snow avalanches is necessary. This project consists of a study into the physical factors that contribute to slab avalanche formation, and a GIS analysis of an avalanche prone area within the Sierra Nevada Mountains. The primary physical factors that contribute to the conditions that lead to avalanches include the slope of a mountain face, the aspect, and bare ground conditions lacking thick forest vegetation. ArcGIS is a powerful software tool that was used to map each of these factors, and then combine them to create …


Modeling Glacial Termination, Michael Murphy Jun 2012

Modeling Glacial Termination, Michael Murphy

Natural Resources Management and Environmental Sciences

Examines possible cause of the glacial termination or ice age cycle using a numerical model created by Tziperman et al. Also explores possible physical mechanisms causing the observed cycle of slow cooling followed by rapid warming.


Estimates Of The Density Contrast At Earth’S Inner-Core Boundary Beneath Central Mexico, Wade Kelley Jun 2012

Estimates Of The Density Contrast At Earth’S Inner-Core Boundary Beneath Central Mexico, Wade Kelley

Physics

Seismograms recorded in the western United States from a Guatemalan earthquake are examined for matching pairs of PKiKP and PcP waveforms for use in estimating the density contrast at earth’s inner-core boundary via a PKiKP/PcP amplitude ratio analysis. Examination of waveforms from the SN, SC, TA, US and CI arrays finds 68 visually identifiable PKiKP and PcP pairs from which 17 were judged to be of sufficient quality (low signal-to-noise ratio) for use in the PKiKP/PcP amplitude ratio analysis. The epicentral distance range of the selected data spans epicentral distances from 22 – 37 degrees inside of which stations are …


A Chemical And Morphological Study Of Soils At The Cal Poly Vineyard, Glade A. Dlott May 2012

A Chemical And Morphological Study Of Soils At The Cal Poly Vineyard, Glade A. Dlott

Natural Resources Management and Environmental Sciences

Despite cultivation for close to a decade, the soils at the Cal Poly vineyard have never been studied in detail. This study was designed to gain a better understanding of the soils for better management. Soil pits and auger holes were dug throughout the site to accurately classify soils. Soils were classified using USDA-NRCS Soil Taxonomy, and samples were taken from each horizon of each soil pit for chemical analysis. Four soil map units were delineated on the site. The pH, EC, total percent carbon and nitrogen, and plant available nitrate, sulfate, phosphate, base cations, and metal micronutrients of each …


Seismic Detection Of A Low-Velocity Layer Atop The 410-Km Discontinuity: Verification Of An Electromagnetically Detected Layer Of Partial-Melt Atop The 410-Km Discontinuity Beneath Se Arizona, Dwight W. Townsend May 2012

Seismic Detection Of A Low-Velocity Layer Atop The 410-Km Discontinuity: Verification Of An Electromagnetically Detected Layer Of Partial-Melt Atop The 410-Km Discontinuity Beneath Se Arizona, Dwight W. Townsend

Physics

No abstract provided.


Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich Apr 2012

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …


Evaluating Geomorphic Change In Little Creek Using Repeated Cross-Sectional And Longitudinal Profile Surveys, Drew Allen Perkins Mar 2012

Evaluating Geomorphic Change In Little Creek Using Repeated Cross-Sectional And Longitudinal Profile Surveys, Drew Allen Perkins

Master's Theses

Six geomorphic study reaches were established in 2002 along a forested mountain stream (gradients range from 0.02 to 0.05) on Cal Poly's Swanton Pacific Ranch in Santa Cruz County, California. These study reaches are a component of paired and nested watershed studies in the approximately 500 hectare Little Creek watershed. The overall goal of this study was to monitor water quality and channel conditions before, during, and after a selective harvest of redwood. A selective harvest occurred in the North Fork of Little Creek in Summer 2008. In August 2009, approximately 90% of the Little Creek Watershed was burned in …


Soil Mapping On A Swanton Pacific Ranch Rangeland, Thomas N. Witman Jan 2012

Soil Mapping On A Swanton Pacific Ranch Rangeland, Thomas N. Witman

Natural Resources Management and Environmental Sciences

Knowledge of soils has become very important in most land based enterprises. The understanding of soils is necessary for all different types of land management projects. The USDA mapped all of the soils in the United States starting in the late 1950’s to provide the necessary information. However because the mappers often times had to map entire counties in short amounts of time ,did not have modern technology, and had rather a vague operating procedure, there was no way to be accurate on the small scaled. To solve this problem I evaluated Dr. Ron Taskey’s landscape hierarchy, a method that …