An oxygen barometer to estimate fO2 during the crystallization of kimberlites is developed using the Fe content of perovskite (Pv), a common groundmass phase in these rocks. With increasing fO2, more Fe exists in the kimberlitic liquid as Fe3+, and thus partitions into Pv, which accepts only Fe3+ into its crystal structure. Experiments to study the partitioning of Fe3+ between Pv and kimberlite liquid were conducted on simple and complex anhydrous kimberlite bulk compositions at 100 kPa over a range temperatures (1130 - 1300°C) and of fO2's from NN0+4 to NNO-5 (NNO, nickel-nickel oxide buffer) and at Nb and REE levels of 0 to 1.5 wt% and 1500 ppm respectively. For Nb-free experiments, the Fe2O3 content of Pv increases with fO2 according to the relation (at 2σ): Fe2O3 Pv (wt%) = 0.25 (0.04) ?NNO + 1.83(0.06) For experiments doped with Nb, two universal equations for the relationship between the Fe and Nb in Pv, and fO2 were defined. Based on a slope intercept fitting method (SIM) we obtain: Log Fe (0.04)=0.058(0.004)* ?NNO + 0.26(0.02)*Log Nb - 0.91(0.03) Based on a multiple linear regression method (MLR): Fe (0.031)= 0.404(0)* NNO + 0.50(0.021)*Nb + 0.030(0.001) with uncertainties at 2o, and Nb and Fe as cation units per 3 oxygens in both equations. Over the range of conditions of our experiments, these relationships show no temperature (T) dependence and are not affected by the bulk Fe content of the kimberlite starting material. The Fe2O3 content of Pv from natural kimberlites compiled from the literature corresponds to fO2 conditions of NNO-5 to NNO+1. Data on zoned Pv from a single kimberlite, the Phoenix pipe, suggests that cores record lower fO2 than rims, NNO-1 in = cores compared to NNO+1 in rims. Within the Somerset Island cluster, Pv from six pipes display an average relative f02 of NNO-4 to NNO+I . Within individual kimberlite pipes, however, the fO2 range recorded by Pv narrows to NNO-2.6 +/- 0.6 within the Nikos 1 pipe, and NNO +1- 2 within the Zulu pipe. Within the Lac de Gras cluster, Pv from five pipes display an average relative fO2 of NNO-2.5 to NNO+6. However, within a single kimberlite, the Grizzly pipe, the fO2 range recorded by Pv narrows to NNO+/- 1. The range in fO2 recorded by Pv may result from the diversity and complexity of processes that ensue during the emplacement of kimberlite magma (crystallization, assimilation and degassing), a detailed record of which is revealed by a comprehensive study of perovskite parageneses in these complex rocks.

The snowball Earth theory. that low-latitude continents became glaciated after sea ice extended from the poles to the equator during the Neoproterozoic (1000 - 545 Ma), has sparked a flood of numerical modelling studies investigating all phases of the proposed extreme climatic cycle. Modelling studies have both supported and refuted the original ‘hard’ snowball theory, as well as offered alternative theories such as the ‘soft’ snowball theory, where glaciers covered all land masses but sea ice did not extend equatorward of -25° latitude. Presented here are a number of sensitivity studies investigating the effects of different sea ice models on snowball inception and how large ranges in accepted albedo values affect the amount of radiative forcing required for deglaciation. These experiments shed light on disparities between previous modelling results. This study demonstrates the importance of a sea ice component's thermodynamic formulation by comparing the physically complete thermodynamic sea ice model in the UVic Earth System Climate Model to an incomplete sea ice model used in an early version of the Fast Ocean Atmosphere Model. As well as the importance of a sound thermodynamic sea ice model is the inclusion of sea ice dynamics. Sea ice dynamics have not previously been included in snowball simulations and their inclusion suggests that the alternative `soft' snowball theory may not be plausible. With a purely thermodynamic sea ice component. the 'soft' snowball state is stable whereas with the inclusion of sea ice dynamics it is not. Also gained from this study was the influence of wind speed on the level of CO2 required to produce a hard snowball solution: greater wind speed results in a cooler ocean and easier snowball inception. Finally, although albedo values are critical for the albedo feedback that initiates snowball inception, they are even more important for determining the amount of radiative forcing required to deglaciate the snowball Earth, as the entire planet is covered by snow and ice. Through a suit of sensitivity studies, the amount of forcing required to deglaciate a hard snowball Earth is found to be extremely sensitive to the snow albedo, sea ice albedo and snow masking depth.

An experimental study of the partitioning of aluminum between olivine and spine] was carried out at 100 kPa over the temperature range 1250-1450°C at an oxygen fugacity 1.8 log units below the quartz-fayalite-magnetite buffer in basaltic starting compositions. The partitioning is temperature sensitive and experimental data can be fitted to the relation: T.al (K) = -10500/ {ln([Al2O3]ol/[Al2O3]SP) - 0.98 *(Cr#-sp-0.5) -- 0.75J where [Al2O3]° and [Al2O3] se are concentrations of Al2O3 in olivine and spinel (wt%), and Cr#-sp is Crl(Cr+A1+Fe3+) in spinel. This thermometer is calibrated for olivine with MgI(Mg+Fe) between 0.87 and 0.93, and spine] with Crl(Cr+Al+Fe3+) between 0.07 and 0.63 and Fe 3+/(Cr+Al+Fe3+) between 0.02 and 0.05. and it reproduces experimental conditions to ±20°C. This thermometer generally yields temperatures lower than the two pyroxene thermometer when applied to natural mantle peridotites. The difference may be caused by inaccuracy in both thermometers or by faster Al diffusion in olivine than Ca diffusion in the pyroxenes. Preliminary investigations of the potential of Cr and Si exchange between olivine and spinel as further geothermobarometers are also presented.

In southern central Yukon Territory, Canada, a northwest-trending 267 Ma ophiolitic assemblage defines the Tummel fault zone (TFZ), which juxtaposes Paleozoic miogeoclinal strata of Cassiar terrane with metavolcanic and metasedimentary rocks of Yukon-Tanana terrane. Basalt, greenstone, and chert occur in the TFZ and are correlated with Slide Mountain terrane. Northeast of the TFZ, pelitic and semipelitic rocks of the Kechika Group are overlain by carbonate of the Askin Group in Cassiar terrane. Southwest of the TFZ, Yukon-Tanana terrane comprises Devonian-Mississippian quartzofeldspathic basement (the Snowcap Complex) overlain by Mississippian clastic and arc-derived rocks of the Drury, Pelmac, and Little Salmon formations. The ca. 105 Ma Glenlyon Batholith and its satellite plutons intrude Cassiar terrane and the TFZ, imposing a contact metamorphic aureole that overprints earlier metamorphic features in rocks of Cassiar and Yukon-Tanana terranes and the TFZ, and indicates pre-105 Ma juxtaposition of these three tectonic assemblages.

The Huckleberry Mine region experienced a complex ice-flow history during the Late Wisconsinan Fraser Glaciation. Cross-cutting and superimposition relationships observed in the field, constrain the relative timing of ice-flow events and indicate that a westerly-directed ice-flow event was followed by a smaller magnitude east to northeast event. This ice-flow reversal can be explained by the existence of an ice divide in the central interior of British Columbia during the Fraser Glaciation maximum. Although ice thickness exceeded relief in the region during the glacial maximum, and glaciers flowed west, up-valley towards the Coast Mountains, locally, ice-flow direction appears to still have been influenced by topography. Basal tills dominate the local Quaternary stratigraphy. These grey, overconsolidated, clayey-silt diamictons typically overlie Early Jurassic Telkwa Formation andesites, but they can also locally overlie advance-phase glaciofluvial sands and gravels. In the vicinity of the Main and East Zone areas, it is common to find visible pyrite and chalcopyrite grains (up to 3 mm in size), and mineralized clasts (pyrite +/- chalcopyrite) in the till matrix. At a 19 m vertical exposure, multiple till units were identified. These basal tills are distinguished primarily by changes in colour, matrix texture, and gravel content. Stratigraphic, sedimentological, lithological, and geochemical data from this exposure provide evidence of an ice-flow reversal in the Huckleberry Mine region during the Fraser Glaciation maximum. Till geochemical data define the locations of known sources of copper mineralization in the Huckleberry Mine region. Maximum, minimum, and median copper values in near-surface basal till samples are 8924 ppm, 29 ppm, and 216 ppm, respectively (n=106), while those for sub-surface basal till samples are 4167 ppm, 18 ppm, and 187, respectively (n=230). Locally developed dispersal trains indicate that mineralization from these sources has been transported towards the east and west. These dispersal trains are detectable in both near-surface and sub-surface basal till samples and also provide further evidence of an ice-flow reversal in the Huckleberry Mine region. Two westward-directed dispersal trains, that are isolated or disconnected from dispersal of the Main Zone area, suggest and that there could be undiscovered bedrock mineralization on Huckleberry Mine property.

Polar ice core records reveal atmospheric methane mixing ratios ([CH4]) changing slowly over time scales the length of glacial-interglacial cycles, and also rapidly over a few decades. Measurement of the δ13CH4 value of gases entrained in glacial ice can help identify the sources of the observed [CH4] changes. To facilitate these measurements, an improved on-line extraction and continuous flow isotope ratio mass spectrometer (CF-IRMS) method was developed. Samples of outcropping ablation-zone ice from Påkitsoq, Greenland were measured for δ13CH4 over the Last Glacial Maximum (LGM) to the Preboreal period (PB). CF-IRMS measurement of the Påkitsoq samples revealed an irregular, spot contamination consisting of elevated [CH4] in the interstitial air, likely due to in-situ methanogenesis. All samples were then filtered to reject contaminated samples by comparison against contemporaneous [CH4] from the GISP2 ice core. The filtered samples show more 13C-enriched δ13CH4 values during cold climatic periods, as well as a potential shift to more 13C-enriched δ13CH4 values across the densely sampled Younger Dryas termination. Interpretation of the stable time periods of the filtered record is aided by a data-constrained 4-box steady-state atmospheric CH4 model run in Monte Carlo mode. From the box model results, tropical wetlands show relatively consistent CH4 flux across all time periods except the YD. The cold, dry climates of the LGM and YD decreased wetland CH4 flux, however the LGM flux is likely compensated (increased) by the additional wetland area available on the exposed continental shelves. Boreal wetlands are an important source of 13C-depleted CH4 during warm periods, and their flux is likely predominantly from thermokarst lakes. Biomass burning CH4 flux increases throughout the deglaciation with fluxes in the Preboreal comparable to present-day. Gas hydrate releases indicate terrestrial hydrates are potentially more important than marine hydrates during the deglaciation. The Påkitsoq δ13CH4 record of the abrupt YD termination suggests that the primary sources responsible for the initial [CH4] increase were a mixture of biomass burning (~40‰) and a boreal wetlands source (~60‰), most likely thermokarst lakes. Perhaps surprisingly, this analysis found no important role for biogenic gas hydrates, or tropical wetlands, in the YD termination [CH4] increase.

In southern central Yukon Territory, Canada, a northwest-trending 267 Ma ophiolitic assemblage defines the Tummel fault zone (TFZ), which juxtaposes Paleozoic miogeoclinal strata of Cassiar terrane with metavolcanic and metasedimentary rocks of Yukon-Tanana terrane. Basalt, greenstone, and chert occur in the TFZ and are correlated with Slide Mountain terrane. Northeast of the TFZ, pelitic and semipelitic rocks of the Kechika Group are overlain by carbonate of the Askin Group in Cassiar terrane. Southwest of the TFZ, Yukon-Tanana terrane comprises Devonian-Mississippian quartzofeldspathic basement (the Snowcap Complex) overlain by Mississippian clastic and arc-derived rocks of the Drury, Pelmac, and Little Salmon formations. The ca. 105 Ma Glenlyon Batholith and its satellite plutons intrude Cassiar terrane and the TFZ, imposing a contact metamorphic aureole that overprints earlier metamorphic features in rocks of Cassiar and Yukon-Tanana terranes and the TFZ, and indicates pre-105 Ma juxtaposition of these three tectonic assemblages.

The main objective of this thesis was to evaluate the use of Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua imagery to estimate chlorophyll-a (chl) concentrations in the surface waters of the Strait of Georgia, located off the southwest coast of Canada. To meet this objective two components were addressed: (1) evaluate chl algorithms using ship-based radiometric and biophysical measurements, (2) evaluate atmospheric correction methods in conjunction with chl algorithms using MODIS Aqua imagery. In Chapter 2, biophysical and above-water reflectance measurements collected in 2006 were used to evaluate the OC3M, standard Garver-Siegel-Maritorena version~1 (GSM01), and a modified version of the GSM01 algorithms for estimating chl concentrations in the Strait. The Strait was generally classified as a case 2 water body, transitioning from chromophoric dissolved organic matter (CDOM) dominant in the central region to possibly particulate dominant in the Fraser River plume region. From these biophysical measurements, results showed that the OC3M algorithm was somewhat effective (r^2 = 0.552) outside the most turbid areas of the Fraser River plume. However, a systematic overestimation of lower chl concentrations was found, which may have been related to the higher CDOM absorption observed throughout the Strait. The standard GSM01 algorithm had moderately good agreement with measured CDOM absorption (r^2 = 0.584) and total suspended solids (TSS) concentrations (r^2 = 0.866), but was ineffective at estimating chl concentrations. Localized characterization of the CDOM absorption, through a hyperbolic CDOM model, improved the modified GSM01 results by providing better agreement with measured CDOM absorption (r^2 = 0.620) and TSS concentrations (r^2 = 0.935). By limiting the GSM01 algorithm to regions with lower combined CDOM and non-algal particulate absorption, the statistical relationship between measured and estimated chl improved (r^2 = 0.690). The further re-interpretation of phytoplankton absorption from the modified GSM01 algorithm with a two-component phytoplankton model resulted in a chl relationship with an r^2 = 0.702 and a linear slope closer to one. However, due to the nature of the GSM01 algorithm, its effectiveness is dependent the accurate characterization of the absorption and backscattering of the optically significant water constituents, which is not always available. Furthermore, the GSM01 algorithm effectiveness is contingent upon the accurate atmospheric correction of the shorter blue wavelengths within satellite imagery. Using unattended fluorometric chl measurements, different atmospheric correction approaches in conjunction with the standard OC3M chl algorithm and modified GSM01 algorithm from Chapter 2 were evaluated in Chapter 3. Atmospheric correction methods that were evaluated included: the standard near infrared (NIR) correction, a shortwave infrared (SWIR) correction, and an adapted version of the correction developed at the Management Unit of the North Sea Mathematical Models (MUMM). The NIR correction with the OC3M algorithm was statistically significant with an adjusted r^2 = 0.759 outside the most turbid portions of the Strait, but had a relatively large RMSE of 0.523, was limited to chl < 21 mg m^-3, and only estimated concentrations for 63% of the pixels. Effectiveness of the SWIR correction was limited with the OC3M algorithm because of the low percentage of estimated chl concentrations (21% of the pixels) and a lower adjusted r^2 = 0.572 outside the more turbid portion of the Strait. The adapted MUMM correction was the most effective, using the spatially averaged aerosol properties from the SWIR correction with the fixed NIR water-reflectance ratio defined by the MUMM method. The MUMM correction with the OC3M algorithm, when limited to pixels outside the Fraser River influence, had an adjusted r^2 = 0.720 and provided chl estimates for 84% of the pixels. The modified GSM01 algorithm was ineffective with all three atmospheric corrections due to the overcorrection of the 412 nm band. Several possible reasons for this overcorrection were identified, including the presence of absorbing aerosols and absorption from atmospheric nitrogen dioxide. When comparing spatial-temporal patterns in the MUMM corrected OC3M image with chl measurements, general spatial patterns and temporal trends match, with some explainable exceptions. Firstly, turbidity typically found near Fraser River plume makes the OC3M algorithm ineffective. Secondly, under lower aerosol reflectance conditions, the signal-to-noise ratio of the SWIR bands can make the spatial identification of the aerosol properties difficult.

Using the wind speed measurements collected at the University of Victoria School-based Weather Station Network over the last several years, an assessment of the local wind power potential is presented focusing on its residential use. It is found that, while the local winds are generally characterized by relatively small mean values, their spacial and temporal variability is large. More wind power is potentially available during the winter season compared to the summer season, and during daytime compared to nighttime. The examination of wind characteristics at 32 stations in the network reveals areas with wind energy potential 1.5-2.3 times larger than that at the UVic location, which represents a site with average wind power potential. The station with the highest potential is found to be that of Lansdowne. The probability distribution of the local wind speeds can be reasonably well described by the Weibull probability distribution, although it is recommended that seasonal variability of local winds be taken into consideration when estimating the Weibull fitting parameters. Based on a theoretical and statistical analysis, wind power output and its dependence on wind power density are estimated for five different locations in Victoria, B.C. Overall, it is found that the largest amount of power can be produced from the wind at Lansdowne during winter where, among the micro and small turbines considered, the FD2.5-300 and ARE10kW, respectively, would produce the largest amounts of power.

This study investigates the contribution of including local stakeholders in the early stages of identifying local attributes of vulnerability, adaptive capacity and resiliency to climate change impacts. The research is specific to two remote coastal communities on Haida Gwaii (The Queen Charlotte Islands), British Columbia. It includes community feedback on research tools, as well as on local attributes of vulnerability and adaptive capacity. I employ multiple methods and a participatory approach for data collection. Using this approach I discovered that some of the attributes I originally believed contributed to vulnerability were perceived by participants as strengthening their community. Other attributes which I believed to be strengthening, were viewed by participants as contributing to vulnerability. This thesis illustrates how the use of multiple methods and a participatory approach contribute to greater knowledge and understanding, by both the researcher and the community, of local attributes of vulnerability and adaptive capacity to projected climate change impacts.