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Ph.D. / Louis Agassiz first raised the concept of a global ice age followed by an intriguing history of both proponents and opponents of the idea simultaneously contributing towards the evolution of geological notions up to the present-day ‘Snowball Earth’ model. The causes of glaciation and the sedimentary, geochemical and stratigraphic feedbacks subsequently received renewed interest. Different deposits of possible Neoproterozoic glacial successions were thus selected for detailed provenance analyses in this study. The successions selected are the Puncoviscana Formation on the Pampia Terrane (Northwestern Argentina), the Sierra del Volcán diamictite of the Tandilia System on the Río de la Plata craton (Eastern Argentina), the Kaigas and Numees Formations of the Richtersveld and Gariep areas on the Kalahari craton (Northwest South Africa and Southern Namibia) and the Karoetjes Kop Formation and Swartleikrans Bed of the Bloupoort Formation of the Vanrhynsdorp region on the Kalahari craton (Western South Africa). Diagnostic physicochemical aspects are utilized to ascertain whether the deposits studied are firstly of glacial derivation and, secondly, to constrain the provenance of every deposit. The latter culminate with identification of a regionally or globally significant event. The Sierra del Volcán diamictite is a glacial diamictite with a depositional age younger than 485±2 Ma and is correlatable with the Upper Ordovician Pakhuis Formation (Table Mountain Group) in South Africa. The recognition of a glacial deposit of Upper Ordovician age in eastern Argentina suggests that the Hirnantian ice sheet cover extended from southwest South Africa to eastern Argentina, stretching from the central Paraná basin across into central and northwest Argentina and southern Bolivia. A proximal glacial marine depositional environment is inferred within a subaqueous outwash fan deposited by sediment gravity flow. Periglacial deposits occur in the Pakhuis Formation, suggesting that the ice sheet had retreated with deposition in glacial outwash plains by braided river systems and windblown loess.

The goal of this thesis was to test the applicability of biomarker analyses to better understand the glacial stratigraphic record of the Hudson Bay Lowlands and Oak Ridges Moraine. A biomarker analysis conducted on three geologic deposits from the Hudson Bay Lowlands showed that they can be differentiated based on organic matter (OM) inputs and stage of diagenesis, relating to paleoclimate and depositional environments. In the second study, a biomarker analysis was applied to samples from ten deposits in the Oak Ridges Moraine. These deposits were differentiated based on OM inputs relating to paleovegetation. Additionally, reincorporation and post-deposition alteration led to sample heterogeneity confirming the current understanding of glacial depositional processes and environments. This thesis shows that biomarker analyses can effectively differentiate and contextualize geologic deposits based on OM inputs and stage of diagenesis. This in turn will provide a more robust understanding of the stratigraphic record.

The goal of this thesis was to test the applicability of biomarker analyses to better understand the glacial stratigraphic record of the Hudson Bay Lowlands and Oak Ridges Moraine. A biomarker analysis conducted on three geologic deposits from the Hudson Bay Lowlands showed that they can be differentiated based on organic matter (OM) inputs and stage of diagenesis, relating to paleoclimate and depositional environments. In the second study, a biomarker analysis was applied to samples from ten deposits in the Oak Ridges Moraine. These deposits were differentiated based on OM inputs relating to paleovegetation. Additionally, reincorporation and post-deposition alteration led to sample heterogeneity confirming the current understanding of glacial depositional processes and environments. This thesis shows that biomarker analyses can effectively differentiate and contextualize geologic deposits based on OM inputs and stage of diagenesis. This in turn will provide a more robust understanding of the stratigraphic record.

Here we examine seasonal grain-size trends on 18 beaches in the Northeastern US and dispersed along the post-glacial coast of Massachusetts (USA) in order to explore the mechanisms influencing median grain size and slope. Over 800 grain size samples were collected along 200 summer and winter cross-shore beach elevation surveys. Obtained grain size and beach slope data are compared to coastal morphology, sediment source, wave height, and tidal magnitude in order to ascertain controls on beach characteristics. In general, median grain size increases with intertidal beach slope in the study region. However, grain sizes along post-glaciated beaches in the study are as much as an order of magnitude coarser for the same beach slopes when compared to beaches for other regions of the US. Grain size and slope for beaches in the northeastern US also exhibit less correlation with oceanographic processes (i.e. wave climate and tidal magnitude). Instead, grain size trends are primarily driven by the composition of nearby glacial deposits that serve as the primary source of sediment to beaches in the study region. Results provide quantitative support for the distribution and composition of legacy glacial deposits rather than oceanographic conditions serving as the predominant governor of beach grain size along post-glaciated coastlines of the Atlantic continental margin.

Despite increasing concern about the presence of heavy metals, pesticides and other toxins in indoor environments, very little is known about the physical and chemical composition of ordinary household dust. This study represents the first systematic investigation of the mineralogical composition of indoor dust in residential housing in Canada. Specimens of dust were obtained from homes in six geographically separate cities in the Province of Ontario: two located on the metamorphic and igneous rocks of the Precambrian Canadian Shield (Thunder Bay and Sudbury), the other four located on Palaeozoic limestone and shale dominated bedrock (Barrie, Burlington, Cambridge, and Hamilton). Forty samples of household vacuum dust were obtained. The coarse fraction (80 – 300 µm) of this dust was subjected to flotation (using water) to separate the organic components (e.g. insect fragments, dander), natural and synthetic materials (e.g. fibres, plastics) from the mineral residue. The mineral fraction was then analyzed using quantitative point counting, polarizing light microscopy, powder X-ray diffraction and scanning electron microscopy methods. Despite the great distances between the sampling localities and the distinct differences in bedrock geology, the mineral fraction of dust from all six cities is remarkably similar and dominated by quartz and feldspar, followed by lithic fragments, calcite, and amphibole. Some evidence of the influence of local geology can nevertheless be found. For example, a relatively higher proportion of sulphide minerals is observed in the two cities on the Canadian Shield where these minerals are clearly more abundant in the bedrock. Specimens from Sudbury, Canada’s largest mining centre located atop a nickel-sulphide mineral deposit, showed the highest sulphide contents. Quartz is the dominant mineral in all cities. All quartz grains have internal strain features and fluid inclusions that are indicative of a metamorphic-igneous provenance. In all cities, sand is used on the streets as an abrasive for traction during the icy winter season. This sand is obtained in all cases from local glaciofluvial deposits that were ultimately derived principally from the rocks of the Canadian Shield in the last Pleistocene glaciations that affected all of Ontario. Thus, tracking in sand is the most plausible mechanism by which quartz was introduced into these homes since sampling was done, in all cases, in the winter season. The results indicate that glacial deposits dominate the mineral composition of indoor dust in Ontario cities and that nature of the bedrock immediately underlying the sampling sites is relatively of minor importance.

Despite increasing concern about the presence of heavy metals, pesticides and other toxins in indoor environments, very little is known about the physical and chemical composition of ordinary household dust. This study represents the first systematic investigation of the mineralogical composition of indoor dust in residential housing in Canada. Specimens of dust were obtained from homes in six geographically separate cities in the Province of Ontario: two located on the metamorphic and igneous rocks of the Precambrian Canadian Shield (Thunder Bay and Sudbury), the other four located on Palaeozoic limestone and shale dominated bedrock (Barrie, Burlington, Cambridge, and Hamilton). Forty samples of household vacuum dust were obtained. The coarse fraction (80 – 300 µm) of this dust was subjected to flotation (using water) to separate the organic components (e.g. insect fragments, dander), natural and synthetic materials (e.g. fibres, plastics) from the mineral residue. The mineral fraction was then analyzed using quantitative point counting, polarizing light microscopy, powder X-ray diffraction and scanning electron microscopy methods. Despite the great distances between the sampling localities and the distinct differences in bedrock geology, the mineral fraction of dust from all six cities is remarkably similar and dominated by quartz and feldspar, followed by lithic fragments, calcite, and amphibole. Some evidence of the influence of local geology can nevertheless be found. For example, a relatively higher proportion of sulphide minerals is observed in the two cities on the Canadian Shield where these minerals are clearly more abundant in the bedrock. Specimens from Sudbury, Canada’s largest mining centre located atop a nickel-sulphide mineral deposit, showed the highest sulphide contents. Quartz is the dominant mineral in all cities. All quartz grains have internal strain features and fluid inclusions that are indicative of a metamorphic-igneous provenance. In all cities, sand is used on the streets as an abrasive for traction during the icy winter season. This sand is obtained in all cases from local glaciofluvial deposits that were ultimately derived principally from the rocks of the Canadian Shield in the last Pleistocene glaciations that affected all of Ontario. Thus, tracking in sand is the most plausible mechanism by which quartz was introduced into these homes since sampling was done, in all cases, in the winter season. The results indicate that glacial deposits dominate the mineral composition of indoor dust in Ontario cities and that nature of the bedrock immediately underlying the sampling sites is relatively of minor importance.

Despite increasing concern about the presence of heavy metals, pesticides and other toxins in indoor environments, very little is known about the physical and chemical composition of ordinary household dust. This study represents the first systematic investigation of the mineralogical composition of indoor dust in residential housing in Canada. Specimens of dust were obtained from homes in six geographically separate cities in the Province of Ontario: two located on the metamorphic and igneous rocks of the Precambrian Canadian Shield (Thunder Bay and Sudbury), the other four located on Palaeozoic limestone and shale dominated bedrock (Barrie, Burlington, Cambridge, and Hamilton). Forty samples of household vacuum dust were obtained. The coarse fraction (80 – 300 µm) of this dust was subjected to flotation (using water) to separate the organic components (e.g. insect fragments, dander), natural and synthetic materials (e.g. fibres, plastics) from the mineral residue. The mineral fraction was then analyzed using quantitative point counting, polarizing light microscopy, powder X-ray diffraction and scanning electron microscopy methods. Despite the great distances between the sampling localities and the distinct differences in bedrock geology, the mineral fraction of dust from all six cities is remarkably similar and dominated by quartz and feldspar, followed by lithic fragments, calcite, and amphibole. Some evidence of the influence of local geology can nevertheless be found. For example, a relatively higher proportion of sulphide minerals is observed in the two cities on the Canadian Shield where these minerals are clearly more abundant in the bedrock. Specimens from Sudbury, Canada’s largest mining centre located atop a nickel-sulphide mineral deposit, showed the highest sulphide contents. Quartz is the dominant mineral in all cities. All quartz grains have internal strain features and fluid inclusions that are indicative of a metamorphic-igneous provenance. In all cities, sand is used on the streets as an abrasive for traction during the icy winter season. This sand is obtained in all cases from local glaciofluvial deposits that were ultimately derived principally from the rocks of the Canadian Shield in the last Pleistocene glaciations that affected all of Ontario. Thus, tracking in sand is the most plausible mechanism by which quartz was introduced into these homes since sampling was done, in all cases, in the winter season. The results indicate that glacial deposits dominate the mineral composition of indoor dust in Ontario cities and that nature of the bedrock immediately underlying the sampling sites is relatively of minor importance.

Despite increasing concern about the presence of heavy metals, pesticides and other toxins in indoor environments, very little is known about the physical and chemical composition of ordinary household dust. This study represents the first systematic investigation of the mineralogical composition of indoor dust in residential housing in Canada. Specimens of dust were obtained from homes in six geographically separate cities in the Province of Ontario: two located on the metamorphic and igneous rocks of the Precambrian Canadian Shield (Thunder Bay and Sudbury), the other four located on Palaeozoic limestone and shale dominated bedrock (Barrie, Burlington, Cambridge, and Hamilton). Forty samples of household vacuum dust were obtained. The coarse fraction (80 – 300 µm) of this dust was subjected to flotation (using water) to separate the organic components (e.g. insect fragments, dander), natural and synthetic materials (e.g. fibres, plastics) from the mineral residue. The mineral fraction was then analyzed using quantitative point counting, polarizing light microscopy, powder X-ray diffraction and scanning electron microscopy methods. Despite the great distances between the sampling localities and the distinct differences in bedrock geology, the mineral fraction of dust from all six cities is remarkably similar and dominated by quartz and feldspar, followed by lithic fragments, calcite, and amphibole. Some evidence of the influence of local geology can nevertheless be found. For example, a relatively higher proportion of sulphide minerals is observed in the two cities on the Canadian Shield where these minerals are clearly more abundant in the bedrock. Specimens from Sudbury, Canada’s largest mining centre located atop a nickel-sulphide mineral deposit, showed the highest sulphide contents. Quartz is the dominant mineral in all cities. All quartz grains have internal strain features and fluid inclusions that are indicative of a metamorphic-igneous provenance. In all cities, sand is used on the streets as an abrasive for traction during the icy winter season. This sand is obtained in all cases from local glaciofluvial deposits that were ultimately derived principally from the rocks of the Canadian Shield in the last Pleistocene glaciations that affected all of Ontario. Thus, tracking in sand is the most plausible mechanism by which quartz was introduced into these homes since sampling was done, in all cases, in the winter season. The results indicate that glacial deposits dominate the mineral composition of indoor dust in Ontario cities and that nature of the bedrock immediately underlying the sampling sites is relatively of minor importance.