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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Geographies of fidelity : emergent spaces of third sector activity after the Canterbury earthquakes

Dickinson, Simon Bernard January 2017 (has links)
This thesis examines creative trajectories of urban life that irrupted as a result of a series of devastating earthquakes in the city of Christchurch, New Zealand, in 2010-11. In particular, it focuses on third sector organisations (TSOs) that emerged during the recovery period, and examines how these organisations sought to inscribe themselves within the re-emerging city. In doing so, I argue that the rupture afforded by the earthquakes opened up the possibility for the dominant practices of a complex political conservatism to be challenged through the emergence of new and previously restrained claims to the city that have manifested through these TSOs. These organisations have made use of the temporary recovery-spaces of the city, and appear to be working to embed their underlying values and politics in its renewal. Pertinently, this thesis comprehensively explores the ways these emergent organisations were impelled and sustained by improvisations that attempted to invoke and continue a fidelity to the earthquake event. The dominant narrative in the city has since critiqued these emergent organisations as being subsumed by a broader state project that is working to restore a neoliberal and conservative style of politics. Drawing largely upon in-depth participatory research within emergent TSOs, this thesis seeks to evaluate the notion that the creative forces of these organisations have become stripped of radical potential through a gradual incorporation into a more resilient version of the previous political orthodoxy. In doing so, it contributes to literatures on the political possibilities of the third sector by paying attention to the organisational practices that foster alternative logics of performative expression, political engagement and cultural imagination alongside formations of the seemingly neoliberal. By drawing attention towards the tentative probing of sociocultural and material fissures, practices of organisational experimentation and the ethical agency of staff, I argue that the sector might be viewed as fostering spaces through which alternative ethical and political sensibilities are being actively contested on a range of scales. Subsequently, this thesis explores how the foundations and relations that previously made the city legible have been shaken. Accordingly, the research offers a re-reading of the earthquakes that makes an argument for something more complex than an automatic return to the status-quo. It recognises the earthquakes as a series of violent geophysical events that prompted the irruption of some potentially disruptive imaginations, but explores perceptions that the disaster couldn’t impel others. Underpinning discussion on how these imaginations are grasped and sustained is an examination of how possibilities were afforded or curbed by interpretations of what the earthquakes represented (or enabled) in ongoing storylines of the city. Consequently, this thesis explores what it actually meant in practice for these organisations to be faithful to the event.
292

A viscous accretionary prism: InSAR observations following the 2013 Baluchistan, Pakistan earthquake

Peterson, Katherine Elizabeth 01 July 2018 (has links)
Geodetic observations are commonly used to make inferences about the rheology of the lower crust and mantle, frictional properties of faults, and the structure of the Earth following an earthquake. On 24 September 2013, an Mw 7.7 earthquake ruptured a 200 km segment of the Hoshab fault in southern Pakistan. The Hoshab fault is located in the Makran accretionary prism, one of the widest emergent accretionary prisms on Earth. Interferometric synthetic aperture radar (InSAR) time series observations beginning 15 months after the 2013 earthquake capture a large displacement transient in the hanging wall of the Hoshab fault. Using simulations of viscoelastic relaxation and inversions for afterslip along five candidate fault geometries, I find that afterslip alone cannot account for the displacement observed in time series. Instead, I find that the observations can be explained by viscoelastic relaxation of a mechanically weak (viscosity on the order of 1017-1018 Pa s), shallow (>6 km) weak layer within the accretionary prism. First order results indicate this weak layer is between 8-12 km thick with a power law (n=3.5) rheology, and that viscoelastic relaxation is accommodated by dislocation creep at low temperatures. The weak nature of the Makran accretionary wedge may be driven by high pore fluid pressure from hydrocarbon development and underplated sediments.
293

The 1993, Scott Mills aftershock sequence : moment tensor inversion and joint hypocenter determination

Schurr, Bernd D. 07 January 1997 (has links)
Graduation date: 1997
294

Coupling of two natural complex systems: earthquake-triggered landslides

Ghahramani, Masoumeh January 2012 (has links)
This thesis contains two main parts. The first part presents a database compiling 137 landslide-triggering earthquakes (LTEs) worldwide, with magnitudes greater than the minimum observed threshold for causing landslides (M4.5), for the period of 1998 -2009. Our data sources include a comprehensive review of the existing literature on earthquake-triggered landslides (ETLs), and also a USGS-based earthquake catalog (PAGER-CAT) that contains information on earthquake-triggered secondary events. Only 14 earthquakes out of the 137 seismic events induced significant numbers of landslides (>250). We compared the number of ETLs with the total number of earthquakes with M ≥ 4.5 (n=68,734) during the same period of time. The results show that only 0.2 % of ETLs and only 4.5% of earthquakes of M > 6 resulted in landslide. In addition, we compiled a database of 37 large-scale landslides, involving initial failure volumes of greater than 20 Mm3 that occurred worldwide between 1900 to 2010. The database contains large-scale earthquake-triggered (n ETLs=18) and non-earthquake-triggered landslides (n NETLs=20), i.e., ca. 50% of large-scale landslides were induced by seismic activity. Surprisingly, the volume-temporal frequency curves of ETLs and NETLs show almost identical slopes and intercepts. Thus, for a given volume, the annual frequency of ETLs is almost identical to that of NETLs in the 110 year period. In contrast to previous studies, this thesis found that the volume of the largest landslide triggered by a given landslide-triggering earthquake is not a function of earthquake magnitude. Peak ground motions (PGA, PGV, and PSA) were calculated for the 18 large-scale ETLs at the site of each occurrence and the resulting values show a correlation with the volume of landslides below the threshold of ca. 80 Mm3. Above this threshold, the relationship between peak ground motions and ETL volume shows complex and nonlinear behavior. The results suggest that 1) other special conditions are required for significant earthquake-triggered landslides to occur, and 2) that very large earthquake-triggered landslides (volume greater than 80 Mm3) result from complex progressive failure mechanisms initiated by seismic shaking (i.e., above this threshold volume, landslide volume is independent of PGA, PGV, and PSA). A detailed analysis of the two 1985 Nahanni earthquakes and the North Nahanni rockslide triggered by the first main shock is carried out in the second part of the study. The North Nahanni rockslide, Northwest Territories, Canada was triggered by the earthquake of M=6.6 on October 5th, 1985. The slide occurred in a Palaeozoic carbonate sequence along a thrust fault, which partly follows bedding and partly cuts across bedding. The sliding surface within the limestone consisted of two planes; the lower plane dipped at 20° while the upper plane dipped at 35°. Slope stability analysis is performed using discontinuum numerical modeling. Static slope stability analyses indicate that the sliding rock was marginally safe for the sliding surface friction angles of 24o or higher. Dynamic analyses of the co-seismic movements are conducted by applying a series of sinusoidal waves to the base of the model. The amplitudes of the October earthquake's seismic waves are estimated using strong motion data available from the second main shock. The results, from the dynamic analysis indicate that the slope becomes unstable for given seismic inputs at a specific range of friction angles (24o to 30o) for the sliding surface and the deformation behavior of the North Nahanni rock masses is dependent on the frequency of the seismic signals. Because the static slope stability analysis showed that the slope was close to instability prior to the seismic shaking, we suggest that the 1985 Nahanni earthquake operated as a trigger event that accelerated the occurrence of the slide. This finding supports our earlier results of the global scale study, which showed that the triggering event does not change the general trend of the frequency-volume distribution of landslides; however, it can accelerate the occurrence of slope failure.
295

Post processing of cone penetration data for assessing seismic ground hazards, with application to the New Madrid seismic zone

Liao, Tianfei 17 May 2005 (has links)
The seismic cone penetration test (SCPTu) is the most efficient means for geotechnical site characterization and the evaluation of seismic ground hazards. In this thesis, software systems including ShearPro, ClusterPro, and InSituData, are developed to automate post processing of these SCPTu data. ShearPro is developed to automate the post-processing of the shear wave signals. ClusterPro uses the proposed three-dimensional cluster analysis approach for soil stratification. InSituData facilitates the post processing of penetration data for seismic ground hazards analysis. A new three-dimensional soil classification chart is also proposed in this thesis to help discern soil layers that may be subject to seismic ground hazards, such as loose liquefied sands and silty sands. These methods are then applied to SCPTu data collected at previously-identifed paleoliquefaction sites located in the New Madrid Seismic Zone (NMSZ). For liquefaction evaluation, the cyclic stress ratio (CSR) is computed using site response analysis by DeepSoil and a measured profile of shear waves derived from the 30-m SCPTU soundings and deep suspension loggings in AR and TN. The natural resistance of the soil to liquefaction, termed the cyclic resistance ratios (CRRs), is evaluated based on both deterministic procedures and probabilistic procedures. Based on liquefaction evaluation results at selected paleoliquefaction sites, regional CRR criteria for liquefaction are developed for the NMSZ. As even the latest major earthquakes in NMSZ occurred nearly 200 years ago, aging effects might be an important factor to consider in utilizing the liquefaction criteria to assess the seismic parameters associated with the previous earthquakes. The aging effects in the NMSZ were investigated through large scale blast-induced liquefaction tests conducted in the NMSZ. Then a procedure to estimate seismic parameters associated with previous earthquakes is proposed. It utilizes both the liquefaction criteria based on SCPTu tests and the empirical attenuation relations developed for the corresponding regions. The approach is validated through data evaluation related to the 1989 Loma Prieta earthquakes in California and then applied to previous historic earthquakes in the NMSZ.
296

Fragility Methodology for Performance-Based Engineering of Wood-Frame Residential Construction

Li, Yue 19 August 2005 (has links)
Hurricanes and earthquakes have caused extensive property damage to wood-frame residential construction in the past two decades in the United States. In order to improve residential building performance and mitigate losses from hurricane and earthquake hazards, there is an urgent need for better understanding of building performance and improvements in design and evaluation tools. In this study, a fragility analysis methodology is developed for assessing the response of light-frame wood construction exposed to extreme hurricane winds and earthquakes. The fragility is a conditional limit state probability, presented as a function of the 3-second gust wind speed (hurricanes) or spectral acceleration at the fundamental period of the building (earthquakes), leading to a relation between damage state probability and the hazard stipulated in ASCE Standard 7. A fully coupled probabilistic framework is proposed to assess reliability of the residential construction through convolution of the structural fragility model with hazard models. Finally, a comparative risk assessment addresses the similarities and differences in competing hurricane and earthquake hazards. The tools above can be used to evaluate new and existing building products, model the uncertainties that are inherent to the prediction of building performance, and manage the risk that is consequent to these uncertainties economically
297

A passive seismic investigation of the crustal structure under Ohio /

Brandeberry, Jessica L. January 2007 (has links)
Thesis (M.S.)--University of Toledo, 2007. / Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science in Geology." "A thesis entitled"--at head of title. Accompanied by CD-ROM which contains the following files: 2000-2003 Teleseismic Reduced Traveltimes.xls; 2000-2003 Teleseismic Traveltimes.xls; 2004 Teleseismic Reduced Traveltimes.xls; 2004 Teleseismic Traveltimes.xls; 2005 Teleseismic reduced Traveltimes.xls; 2005 Teleseismic Traveltimes, xls; 2006 Teleseismic Reduced Traveltimes. xls; 2006 Teleseismic Traveltimes. xls; Complete Thesis.doc; Regional Earthquake Data.xls; Teleseismic Earthquake Data.xls. Bibliography: leaves 78-80.
298

Vulnerability of port and harbor communities to earthquake and tsunami hazards in the Pacific Northwest /

Wood, Nathan J. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2003. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.
299

Earthquake nucleation on geometrically complex faults

Fang, Zijun, January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 20, 2010). Includes bibliographical references. Also issued in print.
300

Roles of plate locking and block rotation in the tectonics of the Pacific Northwest /

Ning, Zuoli. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (p. 127-141).

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