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Characterizing Landslide Movement at the Boulder Creek Earthflow, Northern California, Using L-band InSARStimely, Laura Lyn, 1982- 09 1900 (has links)
ix, 60 p. : col. ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Spatial and temporal patterns of movement of the Boulder Creek earthflow were
investigated using 26 interferograms derived from ALOS satellite radar images acquired
between February 2007 and February 2008. Persistently unstable hillslopes in Northern
California are ideally suited to the study of the dynamics and morphological signature of
earthflows, as the deeply sheared melange lithology, high seasonal rainfall, and fast uplift
rates promote widespread deep-seated landsliding. In addition to identifying multiple
active landslides in the region, L-band InSAR reveals varying deformation rates in the
accumulation, transport, and toe regions of the Boulder Creek earthflow. Downslope
displacement rates up to 1.8 m/yr are observed on the earthflow over a I-year period. The
pattern of deformation is similar to that observed from 1944-2006 inferred from aerial
photography. Interferograms highlight spatially variable rates controlled by lithology and
gullies, and movement correlates with seasonal rainfall with a phase lag of ~2 months. / Committee in Charge:
Dr. Joshua J. Roering, Chair;
Dr. David A. Schmidt;
Dr. John M. Logan
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Detecting Landscape Response to Perturbations by Climate and Base Level in Central Pennsylvania Using In-Situ 10Be and 26AlDenn, Alison R 01 January 2017 (has links)
The change of topography with time and the consequent structure of Earth's surface is dependent on the production and transport of weathered bedrock. I use measurements of in-situ cosmogenic 10Be to investigate erosion rates and exposure ages of boulders, streams, and hillslope sediments in central Pennsylvania, a landscape shaped by glacial/interglacial climate cycles and changes in base level. I measure rates of landscape change at three separate sites, Hickory Run boulder field, Young Womans Creek watershed, and Garner Run, a small upland catchment bounded by two ridgelines.
Hickory Run Boulder field is the largest of its kind in the eastern United States. This enigmatic, 1-km-long field of boulders has been attributed to frost-induced processes during the last glacial maximum, when the Laurentide ice sheet margin was nearby. My isotopic data demonstrate that Hickory Run, and likely many other similar boulder fields in eastern North America are ancient, multigenerational features that have persisted over many glacial-interglacial cycles. These findings add nuance to the conventional view of periglaciation as a force that "wiped the slate clean" in the Appalachian Mountains -- in upland areas with resistant lithologies, I show that the landscape was reworked, but not reset by repeated periglaciation.
Young Womans Creek is a 230 km2 drainage basin in the headwaters of the Appalachian Plateau physiographic province, where I investigate the role of non-equilibrium topography on the rates of erosion at a basin scale. Here, I use in-situ 10Be to understand the influence of fluvial incision into the landscape, contrasting erosion rates in undissected uplands with those in incised valleys. Erosion rates are positively correlated with slope, but correlate negatively with normalized channel steepness, ksn, and downstream distance. My results demonstrate the effects of lithology and base level on erosion rate are difficult to disentangle, and that when studied on a small scale, lithology exerts the strongest control over the spatial variability of erosion in a transient landscape.
Resistant sandstone ridgelines such as those at Garner Run are common features in the Ridge and Valley province of central Pennsylvania. At this site, I strive to understand the influence of periglacial activity on the generation and movement of sediment downslope. My measurements demonstrate that sediment in small upland catchments such as Garner Run can have cosmogenic nuclide concentrations equal to and exceeding 100,000 years of surface exposure history. Despite perturbations by multiple glacial/interglacial cycles throughout the Pleistocene these sandstone-underlain environments are not young, and the exposure of surficial materials predates the last major advance of the Laurentide Ice Sheet at ˜26,000 years ago.
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Dating and origin of late quaternary catastrophic shoreline activity around the Mediterranean SeaWood, Philip B. January 1997 (has links)
No description available.
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The vegetation history of the Shirdley Hill Sand in south-west LancashireBaxter, Janet January 1983 (has links)
No description available.
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Comagmatic Evolution of the Boulder and Pioneer Batholiths of Southwest MontanaBankhead, John 08 August 2017 (has links)
The tectonic region that encompasses Southwestern Montana is a petrologically complex area containing several batholiths and thrust faults, underlined by Precambrian basement rock and capped by sedimentary rocks. Intrusive volcanism of Southwest Montana best represented by the Pioneer and Boulder batholiths is a product of the eastward subduction of the Farallon Plate underneath the North American Plate during the Mesozoic time. Geochemical modeling made evident that the Pioneer and Boulder batholiths have a comagmatic relationship. This conclusion is derived from variation, spider and REE diagrams along with petrographic and geochemical models. The intrusion of these batholiths is likely related to the emplacement of a detached portion of the Idaho batholith known as the Sapphire block. Future models that are outside of the scope of this research must consider the evidence proposed in this document to produce an overarching model for the intrusion of the Pioneer and Boulder batholiths in the incredibly dynamic tectonic setting of the Mesozoic.
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Community assembly of benthic invertebrates on island-like marine hard substrataMeyer, Kirstin 21 November 2016 (has links)
Most of the seafloor is soft sediment, so hard substrata are isolated and island-like. In this dissertation, I explore how species distribution patterns on isolated marine hard substrata resemble terrestrial island communities, drawing on classical island biogeography theory and assembly rules, and describe how benthic invertebrate communities assemble in these island-like habitats.
Higher species richness occurred on larger substrata (dropstones and shipwrecks), paralleling terrestrial island communities. However, while larger islands have greater habitat diversity and primary productivity, marine hard substrata are simpler habitats. Greater elevation in the benthic boundary layer may expose fauna to faster current, higher food supply and larval flux. Substrata located closer together had more similar communities, another pattern that resembles terrestrial islands. Dropstone fauna had a clumped distribution, indicating that larvae may disperse among substrata located close together, resulting in similar communities.
In Svalbard fjords, benthic megafaunal communities were significantly different between Arctic- and Atlantic-influenced fjords. Depth and temperature had the greatest influence, with the highest diversity occurring in cold Rijpfjorden and on the north Svalbard shelf.
Recruitment in Svalbard fjords was spatially and temporally variable, with lower recruitment in Rijpfjorden than in Atlantic-influenced fjords and lower recruitment at greater depth. Most of the recruits in Svalbard fjords were fast-growing, poor-competitive opportunists. On shipwrecks, communities showed two mechanisms of colonization: mobile fauna with long-dispersing planktotrophic larvae, and encrusting fauna with lecithotrophic larvae. Encrusting species reproduce asexually to cover the wreck surface, and philopatry may build up dense populations, leading to uneven communities.
On terrestrial islands, non-random co-occurrence is attributed to interspecific competition, but for marine substrata, there may not be a relationship. Fauna were distributed randomly on settlement plates in Svalbard fjords, even when interspecific competition was observed. On dropstones, some morphotypes co-occurred non-randomly in the absence of overgrowth competition. Non-random co-occurrence on isolated marine hard substrata may be a result of restricted larval dispersal (for pairs co-occurring less than by chance) or epibiontism (for pairs co-occurring more often than by chance). While species distribution patterns on island-like marine hard substrata resemble terrestrial islands, the mechanisms are not necessarily the same.
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Glacialgeologi i fjällranden : Undersökning för att spåra värdberget till ett zinkmineraliserat blockOlausson, Lotta January 2012 (has links)
The valleys southwest of Storuman has been exploration targets for sulfide mineralizations like the Laisvall Pb-Zn deposit since the late 1900 when several mineralized boulders where found. No previous glaciogeological survey has been made. This report focus on the directions of local paleoiceflows and glacial transportation in the area of Skikkisjön, the location of the westernmost mineralized boulder, found in 2010. The aim of this study has been to create a picture of the glaciogeological evolution of the area in order to determinate possible hostrock areas. My results suggest that the geomorphology and transportation occurred during a western icedivide located in the nearby mountainrange. The survey area is characterized by topographically controlled iceflows witch appears to be linked between the valleys. The iceflow velocity was considerably higher in the major valleys compared to the surrounding areas indicated by the distribution of longtransported material.
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Madame de Staël et Henri Heine : les deux Allemagnes /Sourian, Ève. January 1974 (has links)
Thèse--Lettres--Boulder--University of Colorado, 1970. / Bibliogr. p. 191-198.
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Considerations for Informed Pursuit of Zero Waste: Lessons from Two Case StudiesThangavelu, Jennifer Anne 14 November 2013 (has links)
Starting in the early 2000s, a number of U.S. communities have adopted "zero waste" commitments to reduce waste as much as possible through recycling, composting, and other means. Little in-depth information exists about the impetus for or efficacy of these efforts. The author sought to build knowledge on the topic by conducting case studies of two communities: the zero waste efforts of Boulder, Colorado, and the Zero Waste Zones established in Atlanta. The two cases presented an interesting contrast, in terms of sector driving zero waste: public in Boulder, and private in Atlanta. The study aimed to use the experiences of these two communities, supplemented with background research on materials management and application of relevant theory, to develop a set of considerations for more informed pursuit of zero waste.
The author gathered qualitative data by conducting unstructured interviews of the actors involved with the zero waste efforts in Boulder and Atlanta. Interview questions concerned, e.g., zero waste goals and plans, the impacts of zero waste on the business or organization, and influential individuals or organizations.
The study produced the following set of considerations: Definition of waste determines priorities and impacts of zero waste efforts; responsibility for waste arbitrarily resides with consumers and local government instead of producers; the private, public, and nonprofit sectors each play important roles in waste reduction; local government should not bear the full burden of materials management; and state and federal government can offer useful policy tools to advance zero waste. / Master of Urban and Regional Planning
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Creating bicycle-friendly cities: increasing bicycle ridership through improved safety conditions, bicycle infrastructure, and the support of a bicycle consciousnessBird, Cody January 1900 (has links)
Master of Regional and Community Planning / Department of Architecture / Jason Brody / This report examines the use of bicycling as a transportation alternative to the personal automobile in the United States. It begins with a review of historical trends that caused Americans to move away from bicycling for transportation and choosing to adopt automobiles as the primary mode of transportation. A review of articles, reports, and studies is used to consider the benefits connected with utilitarian cycling and electing to bicycle for transportation. The report focuses on three prominent barriers that affect an individual‟s decision to bicycle: bicycle safety, bicycle consciousness, and bicycle infrastructure. The study discusses how these three obstacles are considerable factors affecting bicycling. The study also discusses a number of exemplary solutions for overcoming these barriers that have been implemented in bicycle-friendly cities in the United States. An analysis of plans and policies for the bicycle-friendly cities of Portland, Oregon and Davis, California is used to determine what historical actions have led to a more complete bicycle network in these two cities which have elected to promote bicycling. An in-depth evaluation of Boulder, Colorado, provides insight for specific plans that have been adopted and strategies that have proven to be successful in improving bicycling for transportation. The report attempts to demonstrate that bicycling can be made a viable means of transportation in United States‟ communities by adopting comprehensive plans and policies that address the challenges of bicycle safety, bicycle consciousness, and bicycle infrastructure simultaneously.
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