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Full-Text Articles in Physical Sciences and Mathematics

The Fate Of Carbonate Rocks During Hypervelocity Impacts: Case Studies From Three Impact Structures On Earth, Nicolas D. Garroni Feb 2023

The Fate Of Carbonate Rocks During Hypervelocity Impacts: Case Studies From Three Impact Structures On Earth, Nicolas D. Garroni

Electronic Thesis and Dissertation Repository

Approximately 28% of all hypervelocity impact structures discovered on Earth exist in a carbonate-dominated target sequence. Despite decades of research, how carbonate rocks and minerals react to shock metamorphism is still poorly understood. In this contribution, three impact structures on Earth were studied to determine the effects of shock metamorphism on carbonate minerals: Chicxulub, Crooked Creek and Jebel Waqf as Suwwan.

At Chicxulub, carbonates from the impact-melt bearing breccia of drill core, M0077A were characterized petrographically and geochemically. Calcite was the only carbonate mineral present and is abundant throughout the impact breccia in five distinct varieties: limestone clasts …


Uncovering The Mysteries Of Retention Ponds: Comparing The Abundance And Type Of Microplastics In Storm Water Ponds In London Ontario, Natalie Rose Minda Aug 2022

Uncovering The Mysteries Of Retention Ponds: Comparing The Abundance And Type Of Microplastics In Storm Water Ponds In London Ontario, Natalie Rose Minda

Undergraduate Student Research Internships Conference

Microplastics are plastics <5 mm (Liu, 2019; Arthur et al., 2009). They are created in two ways: Intentionally or from the fragmentation of larger pieces of plastic (National Ocean Service, 2021). They can negatively impact human, wildlife and ecosystem health in many ways depending on the exposure, type, size, and shape of the microplastic (Campanale, 2020). Retention ponds are often created in neighborhoods to collect water in order to prevent flooding. They also often serve as habitat for wildlife. Sediment samples were collected in two ponds in London Ontario both dredged in 2016. Samples were processed in the lab and further analyzed under the microscope to isolate the microplastics. Results have not been determined yet, but the abundance and type of microplastic varies in both ponds. Plastic pollution in retention ponds should be considered more, as it poses a threat to human and ecosystem health.


Allostratigraphy Of The Lower Colorado Group (Cretaceous) In South-West Alberta, Slavena Galic Oct 2021

Allostratigraphy Of The Lower Colorado Group (Cretaceous) In South-West Alberta, Slavena Galic

Electronic Thesis and Dissertation Repository

Clastic, upper Albian-lower Cenomanian strata were deposited in a low-accommodation backbulge depozone of the Western Canada Foreland Basin in SW Alberta. These strata are lithologically very heterogeneous and encompass a spectrum of depositional environments along an alluvial to offshore transect. These rocks are assigned, in subsurface, to the Lower Colorado Group, and in outcrop to the upper Blairmore Group. Lithological heterogeneity, as a result of rapid lateral facies changes, resulted in diverse nomenclature that obscured genetic relationships between time-equivalent strata. The present study integrates wireline log, core, and outcrop data to establish a high-resolution allostratigraphic framework which allowed recognition of …


The Impacts Of Mid-Holocene Warming On Water Quality In A Southwestern Ontario Kettle Pond, Morgan E. Peicheff Aug 2021

The Impacts Of Mid-Holocene Warming On Water Quality In A Southwestern Ontario Kettle Pond, Morgan E. Peicheff

Undergraduate Student Research Internships Conference

No abstract provided.


A Periglacial Landsystem Analysis In The Canadian High Arctic: A Tool For Planetary Geomorphology, Chimira Nicole Andres Oct 2020

A Periglacial Landsystem Analysis In The Canadian High Arctic: A Tool For Planetary Geomorphology, Chimira Nicole Andres

Electronic Thesis and Dissertation Repository

Permafrost underlies 50% of Canada’s terrain and underlies 24% of the Earth’s total land area. It is a major driving force in the generation and evolution of patterned ground landforms such as polygons, stone circles, mud boils, and stripes, etc. that are seen on both the surface of the Earth and Mars, specifically in periglacial domains. The distribution of subsurface ice in these landforms (i.e. polygonal terrain) on Earth is a key constraint on past climate and process-form relationships in high arctic and periglacial regions. These landforms also have the potential of storing ice in the subsurface meaning that the …


Detrital Zircon Geochronology Of Paleoproterozoic Sedimentary Rocks From The Upper Huronian Supergroup, Canada, Carolyn M. Hill, Don W. Davis, Patricia L. Corcoran Jun 2019

Detrital Zircon Geochronology Of Paleoproterozoic Sedimentary Rocks From The Upper Huronian Supergroup, Canada, Carolyn M. Hill, Don W. Davis, Patricia L. Corcoran

Western Research Forum

The Huronian Supergroup is a well-known succession of primarily sedimentary rocks exposed north of Lake Huron. Deposition of the succession is constrained between 2450 and 2220 Ma (million years), which corresponds with Earth’s rise of atmospheric oxygen, however the depositional timing of the uppermost formations cannot be refined further due to a lack of interbedded volcanic rocks. A geochronological study of detrital zircon grains from sandstone and claystone beds from the two youngest Huronian formations, the Gordon Lake and Bar River formations, was completed in order to confine the maximum age of deposition.

Zircon is a mineral that commonly forms …


Microfacies Analysis Of Mudstone In A Freshwater To Marine Transect: Upper Cretaceous Dunvegan And Kaskapau Formations, Western Canada Foreland Basin, Katharin Pavan May 2019

Microfacies Analysis Of Mudstone In A Freshwater To Marine Transect: Upper Cretaceous Dunvegan And Kaskapau Formations, Western Canada Foreland Basin, Katharin Pavan

Electronic Thesis and Dissertation Repository

In the Cenomanian-Turonian Dunvegan and Kaskapau formations in Alberta and British Columbia, terrestrial, and nearshore to offshore environments can be related temporally and spatially using a well-established allostratigraphic framework. In these varied environments, ten mudstone microfacies were identified, using optical and scanning electron microscopy. Microfacies 1 through 3 were deposited in a freshwater lacustrine environment by hyperpycnal flows, and consist of rippled, structureless, and inverse-to-normally graded thin beds that record turbulent, laminar, and waxing and waning flow. Microfacies 4 and 5 were deposited from turbulent flow in a fluvial environment. Microfacies 6 represents a paleosol that underlies a maximum flooding …


Sedimentology, Lithostratigraphy And Geochronology Of The Paleoproterozoic Gordon Lake Formation, Huronian Supergroup, Ontario, Canada, Carolyn M. Hill Mar 2019

Sedimentology, Lithostratigraphy And Geochronology Of The Paleoproterozoic Gordon Lake Formation, Huronian Supergroup, Ontario, Canada, Carolyn M. Hill

Electronic Thesis and Dissertation Repository

The Gordon Lake Formation of the Paleoproterozoic Huronian Supergroup is a primarily-siliciclastic succession ranging from 300 to 1100 m thick. Lithostratigraphic and sedimentological analysis of the formation in the Bruce Mines and Flack Lake areas, and Killarney and Lady Evelyn-Smoothwater provincial parks revealed 7 lithofacies, which comprise 3 distinct lithofacies associations. The lithofacies associations are subtidal nearshore, subtidal to shallow shelf, and mixed intertidal flat. Microbially-induced sedimentary structures (MISS) related to microbial mat destruction and decay were recognized in the Flack Lake area. The preserved MISS include sand cracks, mat chips, remnant gas domes, and pyrite patches, and iron laminae. …


Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers, Sarah Peirce, Peter Ashmore, Pauline Leduc Sep 2018

Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers, Sarah Peirce, Peter Ashmore, Pauline Leduc

Geography & Environment Publications

Evolution of bed material mobility and bedload grain size distributions under a range of discharges is rarely observed in braiding in gravel-bed rivers. Yet, the changing of bedload grain size distributions with discharge is expected to be different from laterally stable, threshold, channels on which most gravel bedload theory and observation are based. Here, simultaneous observations of flow, bedload transport rate, and morphological change were made in a physical model of a gravel-bed braided river to document the evolution of grain size distributions and bed mobility over three experimental event hydrographs. Bedload transport rate and grain size distributions were measured …


The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina Aug 2018

The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina

Electronic Thesis and Dissertation Repository

Currently, Mars appears to be in a ‘frozen’ and ‘dry’ state, with the clear majority of the planet’s surface maintaining year-round sub-zero temperatures. However, the discovery of features consistent with landforms found in periglacial environments on Earth, suggests a climate history for Mars that may have involved freeze and thaw cycles. Such landforms include hummocky, polygonised, scalloped, and pitted terrains, as well as ice-rich deposits and gullies, along the mid- to high-latitude bands, typically with no lower than 20o N/S. The detection of near-surface and surface ice via the Phoenix lander, excavation of ice via recent impact cratering activity as …


Sedimentology And Stratigraphy Of The Upper Cretaceous Puskwaskau Formation In North-Central Alberta, Western Canada Foreland Basin, Omar Al-Mufti Jun 2018

Sedimentology And Stratigraphy Of The Upper Cretaceous Puskwaskau Formation In North-Central Alberta, Western Canada Foreland Basin, Omar Al-Mufti

Electronic Thesis and Dissertation Repository

The Santonian to early Campanian mudstone-dominated Puskwaskau Formation was correlated throughout a study area of 50,000 km2 in north-central Alberta using 988 well logs. Fourteen informal allomembers, established by previous studies, are bounded by regionally-mappable marine flooding and/or transgressive surfaces that are traceable for hundreds of kilometres within the study area. These laterally continuous bounding surfaces are parallel to very gently converging, and mostly terminate by onlap onto underlying surfaces. Observations in thin section and in SEM revealed ten mudstone microfacies, grouped into five microfacies associations. The facies preserve evidence for repeated storm-generated reworking of the seafloor. The Puskwaskau …


High-Resolution Allostratigraphy And Sedimentology Of Santonian - Early Campanian Wapiabi Formation In Southern Alberta, Western Canada Foreland Basin, El Mahadia I. Mohammed Apr 2018

High-Resolution Allostratigraphy And Sedimentology Of Santonian - Early Campanian Wapiabi Formation In Southern Alberta, Western Canada Foreland Basin, El Mahadia I. Mohammed

Electronic Thesis and Dissertation Repository

Within a 90,000 km2 study area in SW Alberta, Santonian – basal Campanian strata of the upper Wapiabi Formation are dominated by marine rocks that thin westward from ~300 ~180 m over ~300 km, reflecting apparently spatially uniform flexural subsidence driven by the static load of the orogen. A high-resolution allostratigraphic framework established ten allomembers grouped in four informal tectono-stratigraphic ‘units’, three of which were previously recognized in NW Alberta. In the north and east, the formation is dominated by mudstone organized in numerous metre-scale siltier- and sandier-upward parasequences. A lack of clinoforms and abundant wave-formed sedimentary structures suggest that …


Stratigraphy Of The Upper Silurian To Middle Devonian, Southwestern Ontario, Shuo Sun Feb 2018

Stratigraphy Of The Upper Silurian To Middle Devonian, Southwestern Ontario, Shuo Sun

Electronic Thesis and Dissertation Repository

The upper Silurian–Middle Devonian succession was dominated by carbonate and evaporite deposits, with minor siliciclastic sedimentation, and a significant hiatus across the Siluro-Devonian (S-D) boundary in southwestern Ontario. The stratigraphic units include, in ascending order: Late Silurian Bass Islands/Bertie formations and Salina G Unit, the Devonian Oriskany Formation, Bois Blanc Formation (including Springvale Member), Detroit River Group (including the Lucas, Amherstburg and Sylvania formations), Onondaga Formation, and Dundee Formation.

Below the S-D unconformity, the upper Silurian Bass Islands/Bertie formations are predominantly dolostone of peritidal-sabkha origin and episodic subaerial exposure. Revised stratigraphic correlation shows that the Bertie Formation is older than …


Allostratigraphy, Paleogeographic Evolution And Accommodation Controls Of The Lower Colorado Allogroup In West-Central Alberta, Canada (Western Canada Foreland Basin), Steve Morrow Oct 2017

Allostratigraphy, Paleogeographic Evolution And Accommodation Controls Of The Lower Colorado Allogroup In West-Central Alberta, Canada (Western Canada Foreland Basin), Steve Morrow

Electronic Thesis and Dissertation Repository

The Lower Colorado allogroup of the Western Canada Foreland Basin is a mud-dominated rock succession of marine, estuarine, and coastal plain depositional origin. Relative sea-level oscillations produced bounding discontinuities that allow the allogroup to be divided into four alloformations: the Joli Fou, Viking, Westgate, and Fish Scales.

Rocks of the Lower Colorado allogroup within the study area record marine depositional environments represented by 9 facies. The facies represent depositional environments ranging from offshore marine to lower shoreface through to upper shoreface and river mouth environments.

Geometric analysis of the isopach maps of the regional allomembers of the Lower Colorado allogroup …


Morpho-Sedimentary Characteristics Of Proximal Gravel Braided River Deposits In A Froude-Scaled Physical Model, Peter Ashmore, Tobias Gardner, Pauline Leduc Jan 2017

Morpho-Sedimentary Characteristics Of Proximal Gravel Braided River Deposits In A Froude-Scaled Physical Model, Peter Ashmore, Tobias Gardner, Pauline Leduc

Geography & Environment Publications

A Froude‐scaled physical model of a proximal gravel‐bed braided river was used to connect the river morphological characteristics, and sedimentary processes and forms, to deposit geometry. High resolution continuous three‐dimensional topographic data were acquired from sequential photogrammetric digital elevation models paired with grain‐size surface maps derived from image analysis of textural properties of the surface. From these data, the full three‐dimensional development of the braided river deposit and grain‐size sorting patterns was compiled over an experimental time period of 41 h during which the model river reworked a large portion of the braided channel. The minimum surface of the deposit …


Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim Dec 2016

Sedimentology And Geochemistry Of The Mixed Carbonate-Siliciclastic Espanola Formation, Paleoproterozoic Huronian Supergroup, Bruce Mines-Elliot Lake Area, Ontario, Canada, Mansour H. Al-Hashim

Electronic Thesis and Dissertation Repository

The Espanola Formation of the Paleoproterozoic Huronian Supergroup is a mixed carbonate-siliciclastic succession. Detailed sedimentological analysis of the formation in the Bruce Mines-Elliot Lake region reveals 17 sedimentary lithofacies, which comprise three distinct lithofacies associations. The lithofacies associations represent, in ascending order, shoreface, offshore, and nearshore (or lagoon) depositional environments along a wave- and storm-dominated shallow siliciclastic marine shelf. Major, trace, and rare earth element analyses of the siliciclastic component indicate derivation from a mainly granodioritic Archean upper continental crust with some contributions from mafic volcanic and/or sedimentary rocks. The results show that the source rocks were subjected to relatively …


Channel Form And Processes In A Formerly Glaciated Terrain, Nathaniel Bergman Nov 2016

Channel Form And Processes In A Formerly Glaciated Terrain, Nathaniel Bergman

Electronic Thesis and Dissertation Repository

Despite that many places around the world in general, and North America in particular, were glaciated during the last ice age, relatively little is known about rivers that evolved over these landscapes once they deglaciated. These rivers are commonly categorized as alluvial with a glacial legacy, and often described as plain gravel-bed or sand-bed rivers. Alternatively, they are considered to be bedrock rivers when the glacial deposits were eroded and underlying rock was exposed. However, ignoring the glacial history of these rivers is scientifically wrong and they should be termed "semi-alluvial". This work shows that classification is important, not only …


Microbially Induced Sedimentary Structures In The Paleoproterozoic, Upper Huronian Supergroup, Canada, Carolyn Hill, Patricia I. Corcoran, Rohan Aranha, Fred Longstaffe Jan 2016

Microbially Induced Sedimentary Structures In The Paleoproterozoic, Upper Huronian Supergroup, Canada, Carolyn Hill, Patricia I. Corcoran, Rohan Aranha, Fred Longstaffe

Earth Sciences Publications

The Paleoproterozoic Gordon Lake and Bar River formations, Huronian Supergroup, contain a variety of sedimentary structures in the Flack Lake area of Ontario, Canada, that have been considered of debatable origin. We identify these structures as microbially induced sedimentary structures (MISS). The preserved MISS are related to microbial mat destruction and decay, and include sand cracks, mat chips, remnant gas domes, pyrite patches, and iron laminae. A biological origin for the fossil structures is supported by their similarities to modern and ancient documented examples of MISS, the sand-dominated nature of the substrate in which they are preserved, and key microtextures …


Factors Controlling The Composition And Lithofacies Characteristics Of The Paleoproterozoic Bar River Formation, Huronian Supergroup, Rohan Dj Aranha Oct 2015

Factors Controlling The Composition And Lithofacies Characteristics Of The Paleoproterozoic Bar River Formation, Huronian Supergroup, Rohan Dj Aranha

Electronic Thesis and Dissertation Repository

The Bar River Formation of the Paleoproterozoic Huronian Supergroup is one of the earliest sedimentary formations deposited following Earth’s Great Oxidation Event. Ten quartz-rich lithofacies were identified near Flack Lake, Ontario. Lithofacies associations resemble multiple, stacked tidal inlet fill sequences, common to mesotidal shorelines. Sedimentary structures, such as herringbone cross-stratification, reactivation surfaces, and wave ripples, support tidal and wave action. Paleocurrent patterns are bimodal to polymodal with a mean paleoflow to the southeast. Potential sources northwest of the study area include Archean Superior Province rocks and the Paleoproterozoic Lorrain Formation. Major and trace element, and oxygen isotope geochemistry support either …


Sedimentology And Allostratigraphy Of The Cardium Formation (Turonian-Coniacian) In Southern Alberta, And Equivalent Strata In Northern Montana, Joel Shank May 2012

Sedimentology And Allostratigraphy Of The Cardium Formation (Turonian-Coniacian) In Southern Alberta, And Equivalent Strata In Northern Montana, Joel Shank

Electronic Thesis and Dissertation Repository

The Turonian-Coniacian Cardium Formation of southern Alberta consists of marine sandstone and mudstone, deposited in a foreland basin over ~2.3 m.y. The formation thins from 150 m in the western foredeep to 50 m 350 km to the east. Correlation of 10 regional flooding surfaces in >1200 well logs and 25 outcrops provides an allostratigraphic framework. Mapping of two previously-unrecognized erosion surfaces (E5.2 and E5.5) reveals additional complexity within sandstone of the Raven River Member.

Facies successions coarsen upwards from thinly-bedded and bioturbated mudstone, to heterolithic facies (either bioturbated or bedded), to clean sandstone. Where conglomerate unconformably overlies this succession, …