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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 …


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 …