Earth Sciences Commons^™

The Effects Of Dissolution On The Silicon And Oxygen Isotope Compositions Of Silica Phytoliths, Andrea Prentice

Electronic Thesis and Dissertation Repository

The δ³⁰Si and δ¹⁸O values of silica phytoliths have applications for reconstructing paleoenvironmental conditions. This study examines the effect of partial dissolution and burning of phytoliths on their isotopic compositions, dissolution behaviour, and physical characteristics (specific surface area, mean particle size, and visual appearance) and discusses problems with the use of phytolith δ¹⁸O and δ³⁰Si values that have been modified in soils in paleoclimate reconstruction. Dissolution experiments were conducted in batch reactors under a range of pH (4-10) and temperature (4-44˚C) conditions. The δ¹⁸O and δ³⁰Si values of …

Morphological And Structural Mapping Of The Oudemans Impact Crater Layered Central Uplift, Mars, Bahareh Kasmai

Electronic Thesis and Dissertation Repository

Central uplifts in large meteorite impact craters provide valuable information about the subsurface geology of planetary bodies. Compared to impact craters on Earth, Martian central uplifts can be well exposed and can be mapped in detail by using satellite imagery. Central uplifts preserve morphological and structural features formed as result of the combination of emplacement during the impact process, post impact modification, and erosion over time. In this study, the Oudemans Crater central uplift (the largest central uplift with layers on Mars) was investigated. Oudemans (9.89 S, 268.1 E) is 124 km in diameter and is located in the Sinai …

Controls On Syenite-Hosted Gold Mineralization In The Western Timmins Camp, Robert A. Campbell

Electronic Thesis and Dissertation Repository

The Abitibi granite-greenstone belt has long been known for its’ world-class Archean

lode gold deposits. With exploration and production commencing in the early nineteen

hundreds and continuing into the twenty-first century, this prolific mining camp is rich

in history, research and precious/base metals. The Thunder Creek deposit and Hwy-144 gold prospect are two recently discovered and exploited syenite associated gold plays in the Timmins Camp. The research compares the Thunder Creek and Hwy-144 properties providing new observations on the variable mechanisms for gold mineralization that can change over a short strike distance (0.5-1.5 km’s) hosted in a geologically similar environment. …

Allostratigraphy Of The Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada, Sarah N. Sweeney

Electronic Thesis and Dissertation Repository

The Upper Ordovician units in Southwestern Ontario record the distal response to the development of the Taconic Appalachian foreland basin. The proximal representation in Ohio and Pennsylvania, contain the Utica/Point Pleasant Play (!). The relationship between the proximal and distal portions of the Taconic Appalachian foreland basin is not clearly defined due to limited chronostratigraphic data and only lithostratigraphic correlations in southwestern Ontario. The first step in evaluating the relationship between the Upper Ordovician succession in Ontario and that in the United States is to develop a high frequency allostratigraphic framework that can be integrated and compared to the frameworks …

Runoff Generation In A Tropical Dry Forest Watershed: Processes, Patterns And Connectivity, Kegan K. Farrick

Electronic Thesis and Dissertation Repository

The lack of understanding regarding the controls that govern runoff generation in tropical dry forests represent a critical gap in the hillslope and catchment hydrology literature. Tropical dry forests account for approximately 42% of the global tropical forests, but represent less than 1% of the forest hydrology literature. Three complementary studies were undertaken in a small tropical dry forest watershed, Mexico, to assess the controls that govern the retention and release of a rainfall in the catchment as runoff. In the first study, the high soil surface hydraulic conductivities, absence of a water repellent surface and low rainfall intensities during …

Seismicity Processes In The Charlevoix Seismic Zone, Eastern Canada, Azadeh Fereidoni

Electronic Thesis and Dissertation Repository

The Charlevoix Seismic Zone (CSZ) is the most seismically active region in eastern Canada, based on the historical and current rate of activity. Several papers contend that the current seismicity in the CSZ represents long-lived aftershock sequences of the 1663 M~7 earthquake, in which the aftershock activity has persisted for hundreds of years. The aim of this thesis is to explore the influence of the 1663 earthquake on the current seismicity in the CSZ. The first part of the thesis has focused on developing a comprehensive earthquake database required for analysis of seismicity. The second part of the thesis has …

A Surface Chemistry Study Of The Effects Of Zinc Sulphate On Sphalerite During Flotation Separation At The Laronde Mine, Dennis M. Laliberty

Electronic Thesis and Dissertation Repository

The LaRonde mine is a gold-rich VMS deposit in the Abitibi Greenstone Belt of Canada. Like many polymetallic ore deposits, loss of sphalerite occurs during the Cu circuit of flotation separation at the mill. Zinc sulphate was tested as a sphalerite depressant. XRD, TOF-SIMS and XPS were used to examine the mineralogy and surface chemistry of ore samples collected at select stages of the milling process in the mill and in the laboratory. Data analyses showed that ZnSO4 likely promotes sulphoxyl and hydroxide adsorption to the sphalerite surface inhibiting Cu activation. Addition of ZnSO4 in the LaRonde mill has reduced …

Peatland-Stream Hydrological And Biogeochemical Connectivity In The James Bay Lowland, Ontario, Meghan Kline

Electronic Thesis and Dissertation Repository

The Hudson-James Bay Lowlands are the second largest peatland dominated area on the planet, and are expected to be particularly vulnerable to future climate change. Changes in climate will affect peatland hydrology and biogeochemistry, impacting the aquatic ecosystems this region supports, however there is limited information about the hydrology and biogeochemistry of this landscape under current conditions. This thesis focuses on assessing the nature of hydrological and biogeochemical connectivity between a fen and 2^nd order channel in the Central James Bay Lowland, Ontario. Specifically the study focuses on the role of preferential hydrological flowpaths in the riparian area, such …

Glacial Stratigraphy Of The Ridge River Area, Northern Ontario: Refining Wisconsinan Glacial History And Evidence For Laurentide Ice Streaming, Maurice Nguyen

Electronic Thesis and Dissertation Repository

Detailed field studies of Quaternary sediments were undertaken during the summer of 2012 in the remote Ridge River area of the Hudson Bay Lowland. Grain size, carbonate, stone lithologic analyses and stratigraphic relations of 31 sites were compiled and revealed two main till units likely deposited by the advance and retreat of the Laurentide Ice Sheet. Based grain size, carbonate, and lithologic data the tills cannot be distinguished and the abundance of distantly transported stones suggests rapid flux of glacial debris from Quebec over the Hudson Platform to the study area. Evidence from stone fabrics, striae, and glaciotectonic structures in …

Magnitude Estimation For Earthquake And Tsunami Early Warning Systems, Attieh Eshaghi

Electronic Thesis and Dissertation Repository

In this study, different magnitude estimation methods were investigated for application to earthquake early warning (EEW) and tsunami early warning systems. This integrated study is divided into two main parts. First, I used strong motion accelerograms recorded by borehole and surface stations from the Kiban Kyoshin network (KiK-net) for Japanese earthquakes with moment magnitude (M) ≥ 5.0 in order to develop ground motion prediction equations (GMPEs). I developed new GMPEs for peak ground acceleration (PGA) and peak ground velocity (PGV) using two different catalogs. The first catalog included earthquakes with 5.0 ≤ M ≤ 8.1 from 1998-2010. In …

The Late Quaternary Paleolimnology Of Lake Ontario, Ryan Hladyniuk

Electronic Thesis and Dissertation Repository

We examined the oxygen isotopic composition of biogenic carbonates, carbon and nitrogen abundances and isotopic compositions of bulk organic matter (OM), and the abundances and carbon isotopic compositions of individual n-alkanes (C₁₇ to C₃₅) for samples from three, 18 m long sediment cores from Lake Ontario in order to: (i) assess how changing environmental parameters affected the hydrologic history of Lake Ontario, and (ii) evaluate changes in organic productivity and sources since the last deglaciation. Knowledge of the hydrologic and ecological behaviour of the Lake Ontario basin during past climate change provides insight into its future …

Peat As An Archive Of Remote Mercury Deposition In The Hudson Bay Lowlands, Ontario, Canada, William James Goacher

Electronic Thesis and Dissertation Repository

Peat from the Hudson Bay Lowlands (HBL) in Northern Ontario, Canada was used to reconstruct historical accumulation of mercury (Hg) over more than 7000 years before present. Nine cores, many with previously published paleoclimate studies, were analyzed for Hg and accumulation rates were calculated. Anthropogenic Hg enrichment factors were calculated based on accumulation rates. A more exclusive calculation of the anthropogenic enrichment factor corroborates modelling efforts that have suggested re-cycling legacy Hg is a much greater contributor to present day deposition than previously thought, but not prior to ~500 cal yrs BP. An older pre-industrial record provides a better background …

The Development Of L-Tectonites In High-Strain Zone Settings: A Multiscale Modeling Investigation, Weiyin Chen

Electronic Thesis and Dissertation Repository

Shape fabrics in high-strain zones are commonly used to constrain deformation processes in the lithosphere. Linear fabric, as a type of shape fabric, usually indicates constrictional strain and is an important feature in orogenic belts. Among all kinds of linear fabrics, the isolated L-tectonites, which are surrounded by strong planar fabrics, are poorly understood. The isolated L-tectonites are generally developed in heterogeneous high-strain zones. Their formation involves heterogeneous and multiscale deformation processes that current single-scale kinematic models cannot explain. To relate isolated L-tectonites in a high-strain zone with its boundary conditions, I apply a multiscale approach. Isolated L-tectonites are regarded …

Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis

Electronic Thesis and Dissertation Repository

Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data.

This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces.

Two …

Shock Metamorphic Effects In Lunar And Terrestrial Plagioclase Feldspar Investigated By Optical Petrography And Micro-X-Ray Diffraction, Annemarie E. Pickersgill

Electronic Thesis and Dissertation Repository

Shock metamorphism, caused by hypervelocity impact, is a poorly understood process in feldspar. This thesis addresses: a) developing a quantitative scale of shock deformation in plagioclase feldspar; b) expanding the utility of plagioclase feldspar for determining shock level; and c) micro-X-ray diffraction as a technique with which to study shock in feldspar.

Andesine and labradorite from the Mistastin Lake impact structure, Labrador, Canada, and anorthite from Earth’s moon, returned during the Apollo program, show shock effects such as diaplectic glass. Planar deformation features are absent in plagioclase, but abundant in terrestrial quartz. A pseudomorphous zeolite phase (levyne-Ca) was identified as …

Shear Zone Influence On The Emplacement Of A Giant Pegmatite: The Whabouchi Lithium Pegmatite, Quebec,Canada, Laurisha Bynoe

Electronic Thesis and Dissertation Repository

The Whabouchi pegmatite is within a transpressional high-strain zone of a metamorphosed volcano-sedimentary belt. A well-developed subvertical transposition foliation and a subvertical stretching lineation are present in this zone. The main body of the Whabouchi pegmatite is parallel to the transposition foliation and branching veinlets from this body have been folded and boudinaged by shear zone deformation. Thus suggesting that the Whabouchi pegmatite intruded syn-kinematically during the deformation of the shear zone. Previously, the Whabouchi pegmatite gave a zircon age of 2577 + 14Ma. The Whabouchi pegmatite is linked geochemically and geochronologically to a large pegmatite body to the south …

The Aricheng Basement-Hosted Albitite-Type Uranium Deposit, Roraima Basin, Co-Operative Republic Of Guyana, South America., Jim A. Renaud

Electronic Thesis and Dissertation Repository

The Kurupung batholith is situated in a west dipping mylonite zone within theTransamazonian-aged Mazaruni granite greenstone terrane. Mylonitic shearing is a result of regional sinistral strike-slip faulting during the post-collisional stage of the Transamazonian orogenic cycle. Deformation was active between 2103 +/- 3 Ma, the age of the batholith, and 1995 +/- 15 Ma, the age of hydrothermal uranium and zircon mineralization. Mineral chemical and geochemical characterization of the batholith identifies a uranium-enriched low-Ti sanukitoid generated by partial melting of slab metasomatized mantle which retained unresorbed Cr-bearing mantle inclusions. Rapid unroofing to greenschist facies conditions at approximately 2094 +/- 5 …

Hydrology And Biogeochemistry Of A Bog-Fen-Tributary Complex In The Hudson Bay Lowlands, Ontario, Canada, Thomas A. Ulanowski

Electronic Thesis and Dissertation Repository

The Hudson Bay Lowlands (HBL) contains 26 Gt C sequestered in a 2 meter thick layer of peat which blankets a quarter of Ontario, Canada. The hydrological and chemical influence of the HBL peatlands to surface waters is recognized, but information on peatland runoff processes and the evolution of groundwater through this vast, carbon-rich landscape remain scant. This study focused on elucidating the groundwater flow patterns of a bog-fen-tributary complex in the central region of the HBL, and estimating exports of groundwater, dissolved organic carbon (DOC), total (THg), and methyl (MeHg) mercury during the 2011 ice-free season. Hydrometric data, combined …

Isotopic Fingerprinting Of Shallow And Deep Groundwaters In Southwestern Ontario And Its Applications To Abandoned Well Remediation, Mitchell E. Skuce

Electronic Thesis and Dissertation Repository

Abandoned hydrocarbon wells in southwestern Ontario can act as conduits for Sulphur water, brines, and hydrocarbons from deep Paleozoic bedrock aquifers. Such leakage may pose a threat to shallow groundwater and the environment. Cost-effective plugging of these wells requires knowledge of the sources of the leaking fluids. This study characterizes the isotopic compositions (δ18OH2O, δ2HH2O, δ34SSO4, δ18OSO4, δ13CDIC, 87Sr/86Sr) of groundwaters in the region, which are distinct in different bedrock formations. A Bayesian mixing model was applied to these data to develop a tool for identifying the source(s) of leaking fluids. The geochemical data also improve our understanding of groundwater …

Statistical Analysis And Computer Modelling Of Volcanic Eruptions, Laura Anabelle Sanchez

Electronic Thesis and Dissertation Repository

Volcanism is an important mechanism by which internal heat is transported to the Earth's surface and volcanic eruptions are the results of the dynamics of a complex system and are characterized by non-trivial temporal correlations. Understanding the processes involved in volcano formation and magma ascent are crucial to develop better hazard assessment techniques. This study focuses on three main points: understanding caldera formation in the solar system, investigating the global temporal behaviour of volcanic eruptions and understanding the nonlinear interactions taking place in the solid crust which lead to an eruption.

In chapter 2, I first examine the distribution of …

Micro-Computed Tomography Semi-Empirical Beam Hardening Correction: Method And Application To Meteorites, David R. Edey

Electronic Thesis and Dissertation Repository

X-ray micro-computed tomography (μCT) is able to non-destructively provide high- resolution 3D images of the internal structures of dense materials such as meteorites. The widespread availability of instruments capable of biomedical micro-computed tomography means there is ample access to scanners for the investigation of geomaterials, but the scan data can be susceptible to artifacts such as beam hardening, a consequence of high X-ray attenuation in these dense materials.

A semi-empirical correction method for beam hardening and scatter that can be straightforwardly applied to available biomedical scanners is proposed and evaluated. This method uses aluminum as a single calibration material to …

The Latte Gold Zone, Kaminak's Coffee Gold Project, Yukon, Canada: Geology, Geochemistry, And Metallogeny, Eric Buitenhuis

Electronic Thesis and Dissertation Repository

The Latte Gold Zone is hosted within complexly tectonically imbricated metamorphic rocks of the Yukon-Tanana terrane. Snowcap assemblage psammitic schist and amphibolite with exotic Slide Mountain ultramafics overthrusts unidentified arc metavolcanics which in turn overthrust the Late Permian Sulphur Creek orthogneiss. Rapid unroofing of the Dawson Range during the Mid-Cretaceous culminated in dextral movement along the Coffee Creek fault system. A set of stacked, ESE–WNW trending, steeply dipping brittle fault structures served as conduits for gold-bearing fluids. Core-logging, detailed petrography, microprobe analysis, and PIMA investigations indicate that Latte is an epizonal orogenic gold deposit. Gold is hosted within arsenian pyrite …

A Detailed Metallogenic Study Of The Mcfaulds Lake Chromite Deposits, Northern Ontario, Jordan E. Laarman

Electronic Thesis and Dissertation Repository

The Black Label, Black Thor and Big Daddy chromite deposits are a series of chromitite layers that are hosted by the 2734.5 +/-1.0 Ma ‘Ring of Fire’ Intrusion in the McFaulds Lake greenstone belt of Northern Ontario. Over 4200 electron microprobe analyses and 142 laser ablation ICP-MS analyses were performed on chromite and record individual fractionation sequences of chromitite below the metre scale. In comparing results, the dunite-hosted Black Thor chromites are higher grade with 53 to 49 wt. % Cr₂O₃, more primitive than Black Label chromites at 50 to 46 wt. % Cr₂O …