This thesis examines the structural and stratigraphic relationships between an Archean clastic sequence of "Timiskaming-like" sedimentary and volcanic rocks and the adjacent Keewatin volcanic terrace.  Field and laboratory studies have shown that mylonitic rocks mark the sheared northern and southern boundaries of the sequence.  Similar clastic sequences are exposed to the west.  The intervening volcanic terrane is characterized by strongly sheared rocks.  The strike of these shear zones closely parallels the boundary shears of the clastic sequence, suggesting that all shear zones are related and form a large, east-west trending major zone of dislocation.  A faulted intrusive contact marks the contact with a granite to the south.  Proterozoic sedimentary rocks are exposed to the southeast and unconformably overlie the Archean rocks.

The rocks of the clastic sequence are cut by a pervasive, east-west striking subvertical cleavage.  Locally the rocks possess a second, northerly striking crenulation cleavage, which as resulted in the formation of kink bands, chevron folds, and minor folds in fine-grained rocks throughout the sequence.  The hinge lines of these minor folds plunge northward at moderate to steep angles.  The crenulation cleavage has not been observed in rocks of the adjacent terrane.

A model is proposed to account for the features found in these rocks.  Strike-slip motion along an irregularly oriented crustal shear zone resulted in the opening of pull-apart basins at releasing bends and uplift at restraining bends which led to local areas of high relief.  Sediments and volcanic debris filled the basin.  The crenulation cleavage is the result of complex motion and local reversals in the shear sense along portions of the fault, which caused compression in part of the basin.

The Deadhorse Creek ‘Diatreme’ is a Proterozoic vent breccia that probably formed in response to early mid-continent rifting.  Following emplacement of the breccia, the western subcomplex experienced three alteration events, producing the complex mineralogy observed in the main mineralized zone.  Each event has produced a unique mineral paragenesis and the timing of each has been deduced from both textural and compositional evidence.  While independent, these events made use of the same pre-existing fracture system along which the western subcomplex is situated.  In order, these events were: intrusion of granitic fluids, alkaline metasomatism, and thermal metamorphism due to the emplacement of the Coldwell alkaline complex.  Following the alteration events, and presumably a result of denudation, oxidization and leaching of the main mineralized zone has produced a supergene paragenesis of:  calcite, tyuyamunite, hollandite and barite.  The main mineralization zone was enriched in first- and second-row transition metals, rare-earth elements, beryllium, Th and U.  The mineralization is represented by the presence of:  aegirine-gervisite, aegirine-natalyite, barite, barylite, hollandite, coffinite, hematite, ilmenorutile, magnetite, monazite-(Ce), phenakite, pyrite, rutile, thorite, thorogummite, thortveitite, tyuyamunite, uraninite, V-crichtonite, xenotime-(Y), zircon, zircon-thorite-coffinite solid solutions and a few unnamed mineral species.  The resulting mineralogy is both unique and complex, with several rare minerals and new compositional extremes reported (i.e., Nb-V-rutile, aegirine-jervisite, aegirine-natalyite, zircon-thorite-coffinite solid solutions, Dy-xenotime-(Y), thortveitite, baotite, barylite and V-crichtonite).  In addition, unique parageneses are reported, giving further insight into the geochemistry of Be, Ba, Sc, V, Nb, Ti and Cr and conditions of formation of phenakite, barylite, thortveitite, crichtonite, ilmenorutile, barian feldspars and zircon-thorite-coffinite solid solutions.

The coaster brook trout populations in Lake Superior have supported a thriving fishery operation since early European settlement in the area.  The pressures from sport and commercial fishing combined with the habitat destruction and fragmentation associated with railroad, highway and industrial growth led to a sharp decline in coaster brook trout populations along the north shore of Lake Superior.  In an effort to restore lost habitat and aid failing fish stocks, tributary streams known to have historically provided habitat are being remediated.  The Kama Creek coaster brook trout realignment project is one such stream.

Historically, Kama Creek recorded high numbers of brook trout and provided important spawning, rearing and overwintering habitat.  The construction of the railroad in 1962 led to a loss of 600 metres of habitat when the stream was straightened, and the culvert became perched.  The realignment of the creek to its original configuration remedied both problems within the stream.

In order to determine the success of the remediation efforts and to determine what, if any work will be required in the future, water loss and sediment transport were examined during the months of April to August 2014.  The data collected during this period indicates little to no water loss to the old channel or groundwater table and a significant amount of sediment transport within the stream which has damaged the intended design of the stream.  Future work should aim to remedy the construction of the stream to better reflect the environmental and physical conditions of Kama Creek and ensure a stable structure can be maintained.

The Anderson Lake Pegmatite is a N-S trending, S-type granitic pegmatite derived from the Hilma Lake Granite within the Quetico Basin of the Superior Province.  It is composed of potassium feldspar – muscovite – quartz – beryl – and molybdenite with accessory ferrocolumbite, apatite and garnet. The pegmatite is crosscut by later vuggy quartz veins which occasionally host amethyst. The molybdenite within the pegmatite is syngenetic and occurs directly within quartz rich areas of the pegmatite, as well as within late stage dark gray quartz veins which crosscut the pegmatite, and in fractured surfaces of the pegmatite with ferrimolybdite. 

The molybdenite occurs as coarse-grained euhedral florets, as well as pod-like aggregates within quartz rich pods of the pegmatite. There are three main trenches along the pegmatite and the molybdenite is most abundant in Trench A, with minor occurrences in Trench B and Trench C. Within Trench C, ferrimolybdite is present within fractures hosting molybdenite. The pegmatite is roughly N-S trending along the contact between the host metasedimentary rocks and the Hilma Lake Granite. The Anderson Lake pegmatite is classified as a molybdenite-bearing Nb-Be tabular pegmatite (beryl-ferrocolumbite). Re-Os dating of the molybdenite from the pegmatite produced an age of 2689 ± 12 Ma, which predates much of the plutonism, metamorphism and subsequent pegmatite injections within the Quetico Basin. 

The associated Hilma Lake granite is classified within this study as an equigranular, coarse-grained monzogranite to syenogranite, containing plagioclase – potassium feldspar – quartz – biotite – muscovite – titanite – garnet – and apatite. The biotite is heavily altered to chlorite with magnetite inclusions between the sheets of the biotite. When plotted on a viii tectonic discrimination diagram (Rb vs. Y + Nb), the Hilma Lake Granite plots within the volcanic arc granite field. This would be expected had they formed during the subduction and transpression of the Wawa Terrane beneath the Wabigoon Terrane, when the Quetico was an accretionary complex composed of sediments derived from the volcanic arcs to the north and south.

There have been many studies investigating microbial mat colonies in carbonate environments, yet few have been completed for siliciclastic settings.  This thesis presents research of microbially induced sedimentary structures from the siliciclastic portion of the Paleoproterozoic Gunflint and Rove Formations, Animikie Group, northwestern Ontario.  Four outcrops were chosen for investigation in the Thunder Bay area based on their depositional environments.  The first of the 3 sites was in the Rove Formation, where the physical features resemble a submarine fan environment with turbidity current deposits.  The other two Rove Formation sites were comprised of fine, parallel laminated black shale near its base.  These 3 sites did not show evidence of microbial communities, while the fourth site in the Gunflint Formation at Current River did.  The outcrop is located north of the famous Gunflint stromatolites on the Eastern River bank of Current River.  Multiple microbially induced sedimentary structures (MISS) were located on the bedding surfaces and were recorded by photograph.  These include:  (a) bulges of mat growth due to repeated wetting of the area, (b) preserved mat chips, (c) Kinneyia wrinkle structures, (d) ripple patches, and (e) similar textures on multiple sand layers indicating extracellular polymeric substances (EPS).  Further inspection using a petrographic microscope revealed (f) wavy-crinkly biolamination and (g) redeposited roll-up structures from the rock samples.  None of these examples can be indisputably proven as microbially induced sedimentary structures, yet these features should be considered as indicators of microbial mats in the siliciclastic sediments of the Gunflint Formation.

Orangeites occur within a sub-parallel en-echelon dike system on several farms near Swartruggens, Transvaal.  Emplaced during the upper Jurassic in an approximately 1 km thick sequence of lavas of the Pretoria series, they are underlain by approximately 1.5 km of highly fractured shale/slate which overlies Transvaal dolomite.  The incompetent and fractured nature of the shale is believed to be responsible for the meandering, splitting, and intertwining nature of the dikes which may vary considerably in thickness over short distances or pinch out rapidly.  Composite dikes are common, with different levels and segments of individual dikes displaying petrographically different character and degrees of alteration.  Evidence exists for multiple intrusions with relatively slow magma-emplacement rates, as demonstrated by the preservation of delicate flow banding as dikes curve around irregular host rock protrusions.

This study of the Swartruggens orangeite was limited to the investigation by transmitted light and electron microscopy of samples from mining levels 3, 4, 6, and 7 of th Helam Mine.  Flow banding is evident in samples from levels 6 east and west and 7 east.  Levels 6 and 7 also contain the greatest diversity and abundance of accessory minerals which commonly include apatite, barite, and calcite.  Less common but important phases are perovskite, wadeite, and an unidentified Ca-Ti-Fe silicate.  Minor phases include strontianite, an unidentified Ca-REE phosphate, zircon, an unidentified Ca-Zr silicate, and diverse oxides and sulphides.  Strontium is a common component in apatite, barite, calcite, and perovskite, with barium present to a lesser extent in some of the apatite and calcite.  Both SrO and BaO contents within these minerals may vary considerably within samples from different levels.  REE-oxides are a minor component of some of the apatite and are present in perovskite in moderate amounts.

Compositionally distinct from archetypal kimberlites, Swartruggens orangeite bears closer similarities to lamproites, but differs sufficiently to preclude classification as such.  The accessory minerals apatite, barite, perovskite, and wadeite are common to both Swartruggens orangeite and lamproites.  Differences include the presence of calcite, a relatively rare mineral in lamproites, in Swartruggens orangeite.  An unidentified Ca-Ti-Fe silicate is unique to Swartruggens.  Common lamproitic phases such as leucite, sanidine, shcherbakovite, and K-Ti richterite are absent from Swartruggens.

Lamproite and orangeite magmas are believed to have similar origins in being the products of partial melting of metasomatized lithospheric mantle.  Unique differences resulting from long term evolutionary patterns of diverse lithospheric sources are believed to be responsible for the production of orangeite magmas within the Kaapvaal craton and lamproite magmas on other cratons, and could produce other types of potassic rocks elsewhere.  A proposal has been suggested to include all potassic magmas within a broad group termed the Metasomatized Mantle Magma (MMM) group reflecting similar petrogenetic processes in their origins.

Hogarth Pit Lake was formed from the continual flooding of the open pit iron mine at Steep Rock Lake near Atikokan, Ontario, Canada.  In the past Hogarth Pit Lake has been toxic to aquatic species, although recent studies are beginning to show that toxicity is no longer a problem.  It was the purpose of this stuffy to relate the sources of the Hogarth Pit Lake waters to the surrounding geological units.  To further the study potential sulphate sources were investigated for any sulphides present in the rock units that may lead to high sulphate levels through oxidation.  Water-rock reactions such as carbonate buffering reactions were used to aid in determining potential sulphide sources producing high sulphate levels through oxidation.  Carbon and sulphur isotope abundances of surrounding rocks and water were another tool used to further aid in determining sulphate sources.  Tributaries from the hangingwall and footwall display a wide range in trace element and stable carbon and sulphur isotope composition.  δ³⁴S water values as low as -3.6€ indicate sulphide oxidation which matches δ³⁴S depleted rock values (>-7.2€).  Water samples show depletions up to -20.3€  δ¹³C while the lowest rock sample is only -4.0€  δ¹³C.  The investigations carried out isolated they pyritic rich Ore Zone as a sulphate source that leads to high sulphate waters by a groundwater source.

The Bol©o Cu-Co-Zn deposit is located on the eastern coast of the Baja Peninsula, Mexico and comprises an area of approximately 90 km². The Bol©o sub-basin is contained entirely within the Santa Rosalía basin and represents a sediment hosted, stratiform copper-cobalt-zinc deposit. Baja Mining Corporation currently holds the mining rights to the area with planned exploitation of the deposit commencing in 2009.

The overriding geological control for the area is the continental rifting that formed the Gulf of California. One of the resultants of this tectonism is that much of eastern Baja is underlain by volcanic rock. Consequently, the Bol©o Formation represents the initial rift fill sedimentary sequence in the Santa Rosalía basin and is approximately 250 to 350 meters thick. There is an initial basal sequence of limestone and gypsum followed by five separate instances of upward coarsening fan-delta cycles. Each cycle can be broadly defined as clay-siltstone-sandstone layer followed by a conglomerate followed by a mineralised layer.

The alteration in the conglomerates can be characterised in two broad patterns. As such, there are alteration trends that can be considered as diagenetic in origin, meaning during and/or as a result of the lithification process. The results of this initial alteration can be further categorised. On the one hand, widespread & pervasive hematisation with an increase in montmorillonite can be observed. On the other hand, calcite alteration can be seen in selected units that are associated with an interbedded gypsum layer. However, the former is not mutually exclusive to the latter.

Conversely, there is another alteration trend only seen specifically that can be considered hydrothermal. In this case, the rocks will have pronounced dolomite alteration combined with the possibility of additional montmorillonite. As a comparison, the tuffaceous claystone in tandem with the conglomerate can be used to define a signature of least alteration. 

For more details about this thesis contact Dr. Andrew Conly

The Canadian Shield is mostly composed of granite, and patches of rock outcrop cover about 30% of the Shield.  Soils on the outcrops are much shallower than forested areas and the vegetation communities that persist on the rock outcrops are not well known.  This thesis explores the control of the physical factors on the soils and vegetation communities that develop on the rock outcrops (barrens) in the Thunder Bay area.  In this thesis I investigate the relationship between parent material and soil chemistry characteristics, and the importance of physical factors in determining species assemblages.  The research area was located in Thunder Bay, Ontario, along the north shore of Lake Superior and included five sites with different parent materials.  The bedrock geology in the area is Archaean (granite) to Proterozoic (Gunflint Formation) in age.  Soil samples were collected in the field and analyzed in the laboratory for: bulk density, moisture content, organic matter content, available nutrients, cation exchange capacity, particle size distribution, water holding capacity, and pH.  Nonmetric multidimensional scaling was used to identify physical factors that control the variation in species assemblages and analysis of variance was used to test for differences in soil characteristics among the sites.  Distinct vegetation communities were present at each site and the physical factors controlling vegetation structure differed among the sites.  Generally the main controlling factors were exposure, pH, organic matter content and available nutrient concentrations.  Significant differences in soil chemistry among the sites were reported that indicates the important role of lithology in soil development.

Throughout the Boreal Forest the bedrock of the Canadian Shield is seen on barren outcrops.  These areas are classified as alternating sequences of bare rock, lichen patches and treed islands.  On the rock barrens soils are typically shallow and the freeze-thaw and wet-dry cycles that characterize these systems result in a stressful environment for the plants and animals that inhabit these systems.  Despite the prominence of these systems on the landscape, particularly in Northwestern Ontario, we know very little about their structure and function.  This study examines soil properties and rates of net nitrogen mineralization and net nitrification of lichen patches and treed islands on three outcrops in Northwestern Ontario. The bedrock geology, slope and aspect of the three sites were similar among the studied sites. The plants and soils were characterized at each of the sites and soil samples were collected from lichen patches and treed islands.  Soil samples were analyzed in the laboratory for pH, carbon to nitrogen ratio, nitrogen concentrations, net nitrogen mineralization and net nitrification.  The lichen patches had thinner, more acidic soils with a lower carbon to nitrogen ratio when compared to the treed islands.  The results from the aerobic incubation showed that there was no difference in the rates of net nitrogen mineralization and net nitrification.  This could be due to immobilization from the microbial biomass.  Nitrogen is one of the limiting nutrients in plant growth as it controls net primary productivity, making it essential to further investigate nitrogen processes that occur on barren outcrops.