Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 27 of 27

Full-Text Articles in Earth Sciences

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo Dec 2023

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …


Soarnet, Deep Learning Thermal Detection For Free Flight, Jake T. Tallman Jun 2021

Soarnet, Deep Learning Thermal Detection For Free Flight, Jake T. Tallman

Master's Theses

Thermals are regions of rising hot air formed on the ground through the warming of the surface by the sun. Thermals are commonly used by birds and glider pilots to extend flight duration, increase cross-country distance, and conserve energy. This kind of powerless flight using natural sources of lift is called soaring. Once a thermal is encountered, the pilot flies in circles to keep within the thermal, so gaining altitude before flying off to the next thermal and towards the destination. A single thermal can net a pilot thousands of feet of elevation gain, however estimating thermal locations is not …


Investigation Of Pervasive Clay Layers And Their Effect On Groundwater Flow Using Electrical Resistivity Tomography In The San Antonio Groundwater Basin, James M. Carlson Jun 2019

Investigation Of Pervasive Clay Layers And Their Effect On Groundwater Flow Using Electrical Resistivity Tomography In The San Antonio Groundwater Basin, James M. Carlson

Natural Resources Management and Environmental Sciences

The United States Geological Survey is developing an integrated hydrologic model of the San Antonio Creek Groundwater Basin to better understand and simulate the integrated surface water and groundwater system. An abrupt 60 meter offset in groundwater depth over a distance of less than one kilometer is observed in well readings within the Cañada De Las Flores region of the groundwater basin. Abrupt changes in groundwater levels are often explained by the presence of a fault in the subsurface vertically offsetting sedimentary units. However, observations of the structural geology of this region indicates that faulting is unlikely and suggests an …


Investigation Into Strath Terrace Production In The Mud Hills, California, Patrick Morley Miller Mar 2019

Investigation Into Strath Terrace Production In The Mud Hills, California, Patrick Morley Miller

Natural Resources Management and Environmental Sciences

Rainbow Basin and Owl Canyon comprise deeply dissected uplands in the Mud Hills region near Barstow, California in the western portion of the Basin and Range geologic province. These erosional landscapes are formed in sediment deposited in a Miocene-time extensional basin. The basin was then filled with sediment before being inverted due to tectonic uplift beginning roughly 10 Ma. Sometime after 250 to 300 ka strath terraces were produced and preserved in the two drainage basins in Rainbow Basin, but not in the single drainage basin of Owl Canyon. The reason behind this difference is the main problem to be …


Quantifying The Environmental Performance Of A Stream Habitat Improvement Project, Cody Morse Aug 2018

Quantifying The Environmental Performance Of A Stream Habitat Improvement Project, Cody Morse

Master's Theses

River restoration projects are being installed worldwide to rehabilitate degraded river habitat. Many of these projects focus on stream habitat improvement (SHI), and an estimated 60%of the 37,000 projects listed in the National River Restoration Science Synthesis Program focus on SHI for salmon and trout species. These projects frequently lack a sufficient monitoring program or account for the environmental costs associated with SHI. The present study used life cycle assessment (LCA) techniques and topographic effectiveness monitoring to quantify environmental costs on the basis of geomorphic change. This methodology was a novel approach to assessing the cost-benefit relationship of SHI. To …


Tectonic Controls On Alluvial Fan Dissection In The El Paso Mountains, Michael Thomas Gaffney Jun 2018

Tectonic Controls On Alluvial Fan Dissection In The El Paso Mountains, Michael Thomas Gaffney

Natural Resources Management and Environmental Sciences

The localized dissection of alluvial fans along the western El Paso Mountains is under question. A relatively minor, south dipping normal fault, previously unmentioned in scientific literature, cuts across Quaternary terraces and alluvial fans in the piedmont of the El Paso Mountains. The linear trend of footwall uplift and the pattern of stream incision into the footwall adjacent to the linear trend of footwall uplift reveal that fan dissection is a result of base level fall caused by ongoing tectonism along the El Paso fault system. The regional importance is discussed as the timing of faulting reveals relatively recent uplift …


A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin Nov 2017

A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin

Natural Resources Management and Environmental Sciences

Marine terrace formation is in many instances attributed to wave action, and shore platforms are often called “wave-cut”. However, alternative models for marine terrace formation suggest that other types of physical and chemical weathering have a more central role in the formation of marine terraces than is widely acknowledged. Roering and Retallack (2012) concluded that the roles of subaerial physical and chemical weathering are significant, and played a major role in the formation of the terraces. In this study, weathering of beach cliffs and shore platforms associated with marine terraces at eight sites in two different locations along the central …


Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord Mar 2017

Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord

Natural Resources Management and Environmental Sciences

There are several factors influencing terrace genesis and terrace types in Bunte Creek. Strath terraces exist at upper Bunte Creek, whereas thick fill terraces exist at lower Bunte Creek. Analysis of these terraces leads to insight on what specific factors lead to their formation. Terraces were mapped along the extent of Bunte Creek. Sediment data and terrace-height data were collected for in order to make a complete analysis of the terraces. Tectonic uplift led to incision and strath terrace genesis at upper Bunte Creek. Climatic forcing and base-level rise caused alluvial aggradation behind a shutter ridge that intersects lower Bunte …


Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey Jun 2016

Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey

Natural Resources Management and Environmental Sciences

The Sierra Nevada batholith represents an archetypal continental arc, although the style of deformation throughout the history of the arc is only poorly understood, in part due to the voluminous nature of Late Cretaceous magmatism that has overprinted earlier structures. The purpose of this study is to gain a better understanding of pre-Late Cretaceous deformation in the Sierra Nevada batholith through a structural and geochronological study of the Jurassic White Fork pluton. A Jurassic age for the White Fork pluton is indicated by its inclusion of numerous 148 Ma Independence dikes, and geochronology on the White Fork pluton is limited …


Quartz Crystal Preferred Orientation And Recrystallization Patterns From Naturally Deformed Rocks Under Constriction, Riley Quine Jun 2016

Quartz Crystal Preferred Orientation And Recrystallization Patterns From Naturally Deformed Rocks Under Constriction, Riley Quine

Materials Engineering

This study analyzes crystal preferred orientation (CPO) patterns within constrictional quartz-rich gneisses. Quartz deformation and CPO patterns are an area of interest because quartz is one of the most prevalent minerals in earth's crust. Understanding the typical way that quartz crystals reorient under different states of strain can provide geologists with an additional tool for understanding paleo-strain. Temperature and strain geometry are two dominant factors that control the orientation of quartz crystals within a rock. Temperature determines which slip planes are active and slip planes typically reorient so that they are perpendicular to maximum stress. Previous workers have suggested that …


Detrital Zircon Geochemistry Of The Nacimiento Block, Santa Ynez Mountains, California, Vincent Zhao Jun 2014

Detrital Zircon Geochemistry Of The Nacimiento Block, Santa Ynez Mountains, California, Vincent Zhao

Natural Resources Management and Environmental Sciences

The long-lived California section of the North American Cordillera is one of the most studied continental margins in the world; however, erosion and deformation in areas along the San Andreas Fault and the Sur-Nacimiento Fault has erased sections of the Cordillera which could provide insight in Cordilleran processes. The lost sections are partially preserved in detrital zircons deposited alongside the arc in fore-arc basins such as in the Toro Formation of the Nacimiento block which represents the coastal central California equivalent to the Great Valley Group, located in the Santa Ynez Mountains. Geochemical analysis of the detrital zircons from the …


Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst Jun 2014

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …


Relationship Of Joint Sets To Folded Diatomite Bedding Of The Miguelito Member Of The Pismo Formation In Montaña De Oro State Park, Michael Mcmahan Jan 2014

Relationship Of Joint Sets To Folded Diatomite Bedding Of The Miguelito Member Of The Pismo Formation In Montaña De Oro State Park, Michael Mcmahan

Natural Resources Management and Environmental Sciences

This study was conducted to determine if the orientations of observed joint sets in the late Miocene diatomite bedding of the exposed Miguelito Member in Montaña de Oro State Park relate to the San Andreas wrench fault compressional forces that caused folding of the formation. Strikes and dips of bedding planes and their corresponding first and second generation joint sets were gathered and compiled into a stereonet program for analysis. A cross section of the bedding plane data shows compressional antiform (fold axis oriented ~304/013) and synform (fold axis oriented ~300/001) features. Previous studies indicate post Miocene, tectonic shortening with …


Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas Dec 2013

Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas

Natural Resources Management and Environmental Sciences

The city of Los Osos sits on top of a coastal groundwater aquifer which is the sole supplier of all its residential, agricultural, and industrial water needs. Lacking a sewer system, the upper aquifer became progressively contaminated with nitrates over several decades. Groundwater pumping eventually shifted to the lower aquifer, however seawater intrusion of the lower aquifer caused by over-pumping has further degraded water quality. The Los Osos groundwater basin provides an excellent field region to examine the utility of geophysical methods for characterizing aquifer structure. In this study shallow (<20 >m) electrical resistivity imaging methods were performed at two …


Surficial Geologic Map Of Kings Canyon: Implications For Relatively Slow Stream Incision Rates, Andrew Farris Dec 2013

Surficial Geologic Map Of Kings Canyon: Implications For Relatively Slow Stream Incision Rates, Andrew Farris

Natural Resources Management and Environmental Sciences

Most of the Kings River in the Sierra Nevada Mountains of California has responded to regional uplift with rapid incision, creating the deepest canyon in the United States. However, Kings Canyon near Cedar Grove is still a mountainous relict landscape with little evidence of fluvial incision. Mapping took place in the Cedar Grove area of Kings Canyon to assess factors and/or processes causing relatively low stream incision rates in the region during Holocene time. A surficial geologic map was created in the field, along with visual observations of the South Fork of the Kings River and characterization of geologic map …


Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman Jun 2013

Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman

Natural Resources Management and Environmental Sciences

No abstract provided.


Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend Jun 2013

Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend

Natural Resources Management and Environmental Sciences

The Iron Canyon Valley, located at the southern end of the eastern Sierra Nevada at the boundary between the Mojave and Basin and Range tectonic provinces, exhibits clear evidence, over graded timescales, of development through monoclinal shifting, which is the tendency of streams flowing parallel to strike over sedimentary rocks to shift down-dip. Although the character of the valley and bedrock dip indicates development through monoclinal shifting, the current stream network is located up-dip on the east side of the valley. Mapping the surficial geology of the valley revealed the presence of dissected alluvial surfaces approximately 85 meters above modern …


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 …


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 …


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.


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 …


Post-Fire Near-Surface Runoff From Small-Scale Rainfall Simulations, Santa Cruz Mountains, Michael Founds Oct 2011

Post-Fire Near-Surface Runoff From Small-Scale Rainfall Simulations, Santa Cruz Mountains, Michael Founds

Natural Resources Management and Environmental Sciences

The influence of environmental variables on the runoff response to a fire is poorly understood. Small-scale rainfall simulation was used to study the factors impacting near-surface runoff following the Lockheed Fire, which occurred on August 12, 2009. A variable speed rainfall simulator was used to rain on 15 different test plots at an average rate of 50mmh-1. Variables of burn severity, time following the fire, soil parent material, vegetation type, and presence of a duff layer were all analyzed using the ratio of runoff to rainfall. The difference in-between burned sites and similar control sites were 19±6%. Only …


Aerial Reconnaissance Of Stream Terraces And Landslides Within Bitterwater Creek Watershed In Kern County, California, Zachary Smith May 2011

Aerial Reconnaissance Of Stream Terraces And Landslides Within Bitterwater Creek Watershed In Kern County, California, Zachary Smith

Natural Resources Management and Environmental Sciences

No abstract provided.


Evidence Of Tectonic Uplift Along The Oceanic Fault Near San Simeon, San Luis Obispo County, California, George Gecy Mar 2011

Evidence Of Tectonic Uplift Along The Oceanic Fault Near San Simeon, San Luis Obispo County, California, George Gecy

Earth and Soil Sciences

Post-Seismic satellite imagery after the 2003 earthquake near San Simeon confirmed 10s of millimeters of north-east side uplift along the Oceanic Fault. In order to determine whether or not there has been a history of tectonic uplift northeast of the Oceanic Fault zone, longitudinal profiles of Morro Creek and San Simeon were made using a digital planimeter and 1:24,000 scale maps. Utilizing the stream profiles, convexities could be observed in the streams coinciding where the streams crossed the Oceanic Fault; of the stream profiles, the convexity along San Simeon Creek could be confirmed to be caused by north-east side uplift …


Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry Mar 2010

Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry

Earth and Soil Sciences

Detrital zircon studies of miogeoclinal sediments can help provide a deeper look into the mechanisms leading to continental breakup by studying the evolution of the continental margin of North America. Few detrital zircon studies have been conducted to support previous research and theories about the sedimentation of the Miogeocline from the Neoproterozoic to the Cambrian. Studies targeted at the Basin and Range province of the western United States show a trend of increasing local sediment sources. We analyzed detrital zircons from the Pilot and Deep Creek Ranges in Nevada and Utah via LA-MC-ICP-MS at the University of Arizona LaserChron Center …


Creation Of Soil Liquefaction Susceptibility Maps For San Luis Obispo & Marin Counties Using Geographic Information Systems., Amelia M. Lowman Dec 2009

Creation Of Soil Liquefaction Susceptibility Maps For San Luis Obispo & Marin Counties Using Geographic Information Systems., Amelia M. Lowman

Earth and Soil Sciences

Liquefaction of soils in response to earthquake shaking is a pressing issue in the state of California. Using Geographic Information Systems, Geological and lithology layers, along with criteria in order to separate out the data into four risk categories, a liquefaction risk assessment map was created for San Luis Obispo and Marin Counties. The accuracy of these maps was then assessed using liquefaction occurrences for San Luis Obispo County, and it was determined that while the map is somewhat accurate, in order to obtain a greater amount of accuracy and increase the usefulness of these maps, more data would need …


Quaternary Deposits Near The San Emigdio Mountains, California: Evidence For A Paleolandscape?, Paul G. Lavelle Nov 2006

Quaternary Deposits Near The San Emigdio Mountains, California: Evidence For A Paleolandscape?, Paul G. Lavelle

Earth and Soil Sciences

Discontinuous low-relief surfaces are scattered throughout relatively high topography within the San Emigdio Mountains, California. These surfaces are considered anomalous, as they are preserved in a dissected, mountainous region that is affected by ongoing orogeny. Previous research has suggested that the low-relief surfaces may represent a once-contiguous alluvial surface. This project utilizes field mapping and sedimentological analysis to determine if the surfaces represent a paleo landscape. What is apparent from field work is the presence of two morphologically distinct lithologic units that most likely represent surficial geologic components of the same relict landscape.