Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 96-115).

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (p. 124-128).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 96-101). Available also in a digital version from Dissertation Abstracts.

Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on July 14, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Mechanical Engineering, University of Alberta. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 52-54).

Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics, March, 2001. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

One of the defining characteristics of hotspot volcanism is the presence of a long-lived, linear chain of age-progressive volcanoes created by the movement of the lithosphere over a stationary melting anomaly. However, the spatial distribution of volcanism at hotspots is often complex and highly variable suggesting that the relationship between magma generation and magma transport at hotspots is poorly understood. Here, I present the results of the first systematic quantitative characterization of the spatial distribution of volcanism at oceanic hotspots. In the first study I develop a novel methodology to characterize the across-strike distribution of volcanism at hotspots and apply it to a catalog of 40 oceanic hotpots. I find that only 25% (10/40) of hotspots exhibit the simple single-peak profile predicted by geodynamic models of melt generation in mantle plumes. The remaining 75% (30/40) of hotspots exhibit a dual- or multi-peak pattern. In the second study, I focus on the across-strike distribution of volcanism at the oceanic hotspots that are sourced by a deep-rooted mantle plume. 14 out of the 15 consensus plume-fed hotspots exhibit a dual-peaked across-strike profile. The spacing between these peaks display a strong negative correlation with lithospheric age, in direct contrast to models of inter-volcanic spacing controlled by elastic plate thickness. This relation suggests a different mechanism controls volcanic spacing at plume-fed hotspots. In the third chapter, I investigate variations in the average topographic profiles over time along the two longest and best-constrained oceanic hotspot tracks: Hawaii and Louisville. I find that the dual-peak across-strike profile of volcanism is a persistent feature at the Louisville hotspot over the entire length of the track examined (spanning a period of more than 65 Myr). In contrast, the dual-peak profile of volcanism at Hawaii is only evident along the most recent portion of the track (i.e., over the last 5 Myr). In total, this thesis represents a significant step foreword in the collective understanding of hotspot volcanism, and introduces a new diagnostic tool for analysis of hotspot influenced seafloor topography.

In an effort to reduce atmospheric carbon dioxide (CO2) emissions and mitigate climate change, it has been proposed to sequester supercritical CO2 in underground saline aquifers. Geological storage of CO2 involves different trapping mechanisms which are not yet fully understood. In order to improve the understanding of the effect of chemical reaction on the flow and transport of CO2, these storage mechanisms are modelled experimentally and numerically in this work. In particular, the destabilising interaction between the fluid hydrodynamics and a density-increasing second-order chemical reaction is considered. It is shown that after nondimensional scaling, the flow in a given physicochemical system is governed by two dimensionless groups, Da/Ra2, which measures the timescale for convection compared to those for reaction and diffusion, and CBo', which reflects the excess of the environmental reactant species relative to the diffusing solute. The destabilising reactive scenario is modelled experimentally under standard laboratory conditions using an immiscible two-layer system with acetic acid acting as the solute. A novel colorimetric technique is developed to infer the concentrations of chemical species from the pH of the solution making it possible to measure the flux of solute into the aqueous domain. The validity of this experimental system as a suitable analogue for the dissolution of CO2 is tested against previous work and the destabilising effect of reaction is investigated by adding ammonia to the lower aqueous layer. The system is also modelled numerically and it is shown that the aqueous phase reaction between acetic acid and ammonia can be considered to be instantaneous, meaning that Da/Ra2 tends to infinity and the flow is therefore governed only by the initial dimensionless concentration of reactant in the aqueous phase. The results from the experiments and numerical simulations are in good agreement, showing that an increase in the initial concentration of reactant increases the destabilising effect of reaction, accelerates the onset of convection and enhances the rate of dissolution of solute. The numerical model is then applied to a real world aquifer in the Sleipner gas field and it is demonstrated how the storage capacity of a potential CO2 reservoir could be enhanced by chemical reaction.