Historically wild rice was important economically and spiritually across much of central and eastern Canada, but the antiquity of its use by Native communities is unclear.  Unlike plant macrofossils, which have traditionally been used to identify this plant in prehistoric contexts, silicophytoliths preserve well in archaeological sites and in carbonized food residue encrusted on clay pots.  This proxy, therefore, promises to yield considerable new insight into the antiquity and intensity of wild rice harvesting in this region.

Various phytolith types from various grasses, sedges and aquatic plants were examined.  However, the focus was kept on rondel phytoliths, a form only produced in grasses.  Thirty-eight grass species were examined, including two species of wild rice (Zizania aquatica and Zizania palustris).  A minimum of three hundred rondels from each grass species were counted from various parts of the plant including the inflorescence, the leaf and the stem.  Based on extensive morphological comparisons of phytoliths produced by wild rice (Zizania spp.), and other native Boreal and Prairie grasses and maize (Zea mays), several phytolith morphotypes were identified that are produced only in wild rice (Zizania spp.).  In general, rondels with four spikes, with one and three indentations, are characteristic of Zizania (spp.).  However, differences between the two wild rice species were not established.

Lake sediments from Lulu Lake in the Lake of the Woods area where modern wild rice grows were analysed to determine if the types identified as being diagnostic of wild rice would be present.  As a preliminary analysis, the presence of wild rice (Zizania spp.) can be identified in small quantities in lake sediments.  Therefore, wild rice (Zizania spp.) phytoliths can be a powerful tool in the identification of the plant in Holocene sediments.

Potsherds with encrusted carbonized residues from the Lake of the Woods and surrounding area were also examined for the presence of diagnostic wild rice (Zizania spp.) and maize (Zea mays) phytoliths.  These archaeological samples are attributed to the Laurel (Middle Woodland), Selkirk (Late Woodland), Blackduck (Late Woodland), and Sandy Lake (Late Woodland) cultures.  Based on the use of diagnostic phytolith types for both wild rice (Zizania spp.) and maize (Zea mays), the presence of both these cultigens was identified in the residues of all four cultures mentioned above.

This is the first time maize (Zea mays) and wild rice (Zizania spp.) have been positively identified in prehistoric carbonized food residues from the Boreal Forest.  Based on pottery types, wild rice (Zizania spp.) and maize (Zea mays) were consumed as early as the Middle Woodland period (Laurel phase).  Based on the samples examined, the evidence of maize (Zea mays) phytoliths in the residue is greater than those of wild rice (Zizania spp.).  However, this might reflect sample bias or most likely biases due to processing of the plants before consumption.  Therefore, the absence of a wild rice (Zizania spp.) phytolith signature might not represent that the plant was not consumed, rather that the parts of the plant with the diagnostic phytolith types were removed before consumption.  

Maize (Zea mays) horticulture during the Late Woodland period in the Lake of the Woods and surrounding area does not seem likely because there is no evidence of gardening, or heavy consumption of this plant.  However, the latter might not be necessary for local horticulture.  In contrast, wild rice (Zizania spp.) stands are common in the Lake of the Woods and surrounding area, and therefore local harvesting of this plant is inferred.

A copy of the thesis can be downloaded here

The Hamlin Lake area is located approximately 120 km southwest of the City of Thunder Bay, Ontario within the Shebandowan greenstone belt of the Wawa Subprovince, Superior Province. The purpose of this study was to understand the relationship between an extensive felsic volcanic rock package and the hydrothermal alteration.

Mapping of the area exposed five major lithologies consisting of mafic metavolcanic rocks, intermediate metavolcanic rocks, felsic metavolcanic rocks, felsic intrusive rocks and iron formation. The felsic metavolcanic rocks vary from rhyolites and banded ash to lapilli tuffs and debris flows, whereas the intermediate metavolcanic rocks are made up of dacites and andesites. The only mafic metavolcanic rocks are the debris flows. The felsic intrusive rocks consist of a quartz-eye porphyry and pink breccia. Primary textures, such as fiamme, can still be observed and which are indicative of a subaqueous environment.

Major and trace element geochemical analyses were undertaken on 200 samples of andesitic to rhyolitic volcanic and volcaniclastic rocks. The major elements have become mobile, whereas the trace elements have remained relatively immobile. Hydrothermal alteration affected the primary textures of the Hamlin Lake area so it was necessary to use trace elements to correctly classify the volcanic rocks. Primitive mantle-normalized (PM) and Zr versus Ti plots were used to separate major suites of rocks and also to determine the tectonic setting. The PM plots showed negative anomalies of the Nb and Ti elements, an indication of a supra-subduction zone setting.

A plot of Zr versus Y was used to establish that the rhyolites and andesites are both of a mildly calc-alkaline affinity and the dacites are strongly calc-alkaline. The VMS classifications of Lesher et al. (1986) and Hart et al. (2004) were used to classify the rhyolites and andesites as FII felsic volcanic rocks, whereas the dacites were classified as FI felsic volcanic rocks. FI felsic volcanic rocks are thought to have originated from a deeper source than the FII felsic volcanic rocks suggesting that the Hamlin Lake volcanic rocks were produced in a mature arc-setting.

Mapping and geochemistry was further supported by analysis of Sm-Nd and oxygen isotopes. Nine samples were analyzed for Sm-Nd isotopes and yielded ε_Nd2700 values from -6.59 to +2.62 suggesting some samples had undergone contamination by older material. Several of the samples were close to the value for 2.7 Ga depleted mantle, but one particular sample with a εNd value of -6.59 showed that it had been affected by contamination that could only be explained by a contaminant that was much older than the surrounding 2.7 Ga rocks. The source of the contamination is likely the result of continentally derived sediments being subducted into the mantle wedge, because oceanic arcs are not underlain by older continental crust.

Thirty-seven samples were analyzed for O isotopes to recognize alteration patterns in the Hamlin Lake area. The area mapped at Hamlin Lake was not large enough to clearly show an alteration halo, but it does show that the samples at Hamlin Lake have elevated δ¹⁸O values, the result of interaction with low temperature hydrothermal fluids.

A copy of the thesis can be downloaded here

The Musselwhite gold deposit, 100% owned and operated by Goldcorp Inc., has cumulatively produced in excess of 2 million ounces since opening in 1997 and has a projected mine life through 2013. It is situated in the North Caribou Lake metavolcanic/metasedimentary belt in the central northwestern portion of Superior Province, approximately 430 km northwest of Thunder Bay, Ontario, Canada. The belt occurs along the contact between the North Caribou Terrane and the Island Lake Domain, with a large, crustal-scale deformation zone forming its eastern margin. The Musselwhite gold deposit is hosted by amphibolite facies metamorphic rocks dominated by banded iron formation (BIF). This study primarily focuses on the Northern Iron Formation (NIF) metasedimentary assemblage, host to the majority of gold mineralization at Musselwhite.

Stratigraphic and geochemical analyses suggest that the lithologies of the NIF assemblage were deposited on Mesoarcheaen mafic to ultramafic volcanic rocks forming the ocean floor. The NIF assemblage and another iron formation lower in the stratigraphy, the Southern Iron Formation (SIF), record hydrothermal regimes associated with, and interrupted by, eruptive volcanic activity. The stratigraphically lowest lithologies in the NIF assemblage, meta-argillite, quartz-grunerite BIF, and magnetite-dominant BIF, were deposited in deep, calm water, in association with venting hydrothermal fluids. These ancient chemical sediments are analogous in geochemistry to modern day deposits in places such as the Red Sea and the East Pacific Rise. Differing Eu contents between chert and magnetite layers indicate that rhythmically changing temperature variations drove the hydrothermal system, imparting the banded nature. The chemically pure chert and magnetite layers of the lower portion of the NIF assemblage contrast with silicate-dominant banded iron formation; the silicate-dominant BIF increases in frequency up stratigraphically. It represents a decreasing hydrothermal system and/or an increase in the rate of clastic sedimentation. Hornblende-garnet and biotite-garnet schists were formed by metamorphism of mudstones composed of eroded material. The sediment that formed the hornblende-garnet schist is the same sediment that comprises the siliciclastic component of the silicate-dominant NIF. Similarly the biotite-garnet schist represents a mudstone, but unlike the hornblende-garnet schist, it is primarily derived from intermediate to felsic volcanic rocks. Lastly the garnet-bearing quartzite represents metamorphosed sandstone eroded from the same intermediate to felsic igneous source rocks as the biotite-garnet schist. Just as there is an overall increase in clastic content upwards through the approximately 30 m thick sedimentary succession, there is also a change from more mafic-sourced debris to a more intermediate/felsic source.

The majority of samples collected from Musselwhite did not experience significant remobilization of typically immobile elements. This is indicated by the relatively linear geochemical ratios between the immobile elements (Al₂O₃, TiO₂, Zr, U, Th, etc.). Even elements that are commonly more mobile (K₂O, Na₂O, etc.) appear to have remained relatively immobile at Musselwhite. The only samples that show significant geochemical change are from shear zones. The gold mineralization is primarily associated with shear zones within the siliciclastic-rich, upper NIF assemblage, where pyrrhotite (possibly originally pyrite) replaced iron oxides and iron silicates. This indicates that the control on areas of gold mineralization was a combination of: 1) the presence of structural zones allowing gold-bearing fluids to move through the NIF, which could act as a geochemical trap for gold; and 2) structural conditions in the siliciclastic-rich NIF that favoured hydrothermal fluid involvement with this unit.

Musselwhite Mine is located on the south shore of Opapimiskan Lake, approximately 480 km north of Thunder Bay. Hosted in the  ~2.8Ga North Caribou Lake greenstone belt of the North Caribou Terrane, Superior Province, Musselwhite is currently classified as a shear hosted orogenic gold deposit. The deposit is hosted in an iron formation within a volcanic pile of intermediate to felsic metavolcanic rocks, metabasalts and komatiitic metabasalts and has been metamorphosed to amphibolite grade.

Twenty biotite and 30 quartz samples have been analyzed for δ¹⁵N, δ¹⁸O and δD from Musselwhite Mine as well as 12 biotite samples from the granitoid rocks surrounding the North Caribou Lake Greenstone Belt. Nitrogen isotopes in biotite from Musselwhite Mine are characterized by a δ¹⁵N range from -1.3 to 11.1 per mil. Oxygen and hydrogen isotopes of biotite samples from the mine range from +7.1 to +10.1 per mil for δ¹⁸O and -55 to -100 per mil for δD.

Oxygen isotope signatures from quartz samples from Musselwhite range from +12.4 to +17.1 per mil. Values for the silicate facies iron formation and mineralized zones are consistent with previous work by Otto (2002) and indicate fluid compositions that fall within both the magmatic and metamorphic range.

Biotite samples from granites and metasedimentary rocks adjacent to the deposit have a δ¹⁵N range of -6.9 to +6.1 per mil. Oxygen and hydrogen isotopic ranges for the granitoid plutonic rocks are +2.0 to +4.0 per mil and -59 to -80 per mil respectively; values are typical of felsic plutonic rocks.

The δ¹⁵N, δ¹⁸O and δD stable isotopic data generated for Musselwhite Mine suggest that magmatic fluids played a role in the formation of the deposit.  

Carissa is working on her PhD at the University of Western Australia in Perth

A copy of the thesis can be downloaded here

Diamond bearing Neoarchean metaconglomerates are present in the Michipicoten greenstone belt, Wawa-Abitibi Subprovince, near Wawa, Ontario. They form a portion of the Dore Metasedimentary rocks in the Arliss Lake subbasin, and unconformably overlie a succession of mafic metabasalts. The conglomerates are transitional into argillite and are also overlain by argillite, which in turn is conformably overlain by metabasalts. The conglomeratic succession has a maximum thickness of 454 meters and is confined to what appears to be a deformed paleovalley at the base of the sedimentary succession.

Three lithofacies associations were recognized, and interpreted to indicate that the Leadbetter Conglomerate represents a high-energy, alluvial fan-delta succession. Lithofacies Association One is dominated by weakly sheared and highly viscous debris-flows and represents the upper reaches of the alluvial fan. Lithofacies Association Two is dominated by superimposed longitudinal bars that represent the transformation of the depositional environment to a mid-fan and lower-fan proximal braided system. Lithofacies Association Three is dominated by distributary channel mouth-bars, graded turbiditic density deposits and argillite facies, which represent a transgression and transition to a delta-front and subsequently pro-delta environment.

Whole rock geochemical studies of the Leadbetter Conglomerate indicated that the elements Co, Ni, Sc, TiO₂, V, Al₂O₃, Y, Nb, Zr, Hf, Ta, Th and U are chemically immobile. The immobile elements were used to investigate possible source rock compositions. A mixture of source rocks (mafic, intermediate and felsic igneous rocks, lamprophyre, and possibly kimberlitic occurrences) contributed sediment to the depositional system of the Leadbetter Conglomerate. Of these mafic volcanic rocks and lamprophyres provided the majority of the sediment. Ratio plots used to investigate whether placer accumulation of the heavy minerals chromite and zircon were present indicated that significant placer accumulation had not occurred.

Possible source rocks for the diamonds include either diamond-bearing, ultramafic, lamprophyre dikes and breccias, which have been observed and described near the Leadbetter Conglomerate, or a more commonly diamond associated rock type, such as kimberlite, which have yet to be observed in the area. The presence of kimberlites could be investigated by a study of mineral chemistry, but that was beyond the scope of this thesis.

Corey is currently working as a geologist for North American Palladium, in December 2010 he will start work with Exxon in Houston.

For more details about this thesis contact Dr. Philip Fralick

A copy of the thesis can be downloaded here

Petrography and mineralogy of the C29/30 Candle Lake kimberlite (Saskatchewan, Canada) was studied to understand the characteristics of the kimberlite. Using standard optical microscopy three units where distinguished; pyroclastic kimberlite; resedimented volcaniclastic kimberlite and a crystal tuff kimberlite unit. Each kimberlite unit has been classified based on textural relationships between magmaclasts and the interstitial matrix, as well as phenocrysts, macrocrysts and minor mineral phases within the magmaclasts. Pyroclastic kimberlites are characterized by carbonate or serpentine interclast matrix supporting amoeboid magmaclasts with protruding macrocrysts and phenocrysts of pseudomorphed olivines. Resedimented units have a serpentine-carbonated interclast matrix that is poorly defined against rounded and fractured magmaclasts. The crystal tuff unit is distinguished by fine-grained (<700 μm) clast supported pyrocrysts of pseudomorphed olivine as well as magmaclasts with thin selvages (<100 μm). The interclast matrix is a serpentine-carbonate mixture.

The mineralogy of the C29/30 is typical of an archetype kimberlite. The minerals analyzed include spinels, serpentine, olivine, carbonates, phlogopite, perovskite, apatite, garnets, ilmenite and magnetite. Three types of spinels where identified; type [1] spinels occur enclosed within macrocrysts and phenocrysts with a TIMAC composition; type [2] spinels nucleate along the edges of the macrocrysts and phenocrysts and have a TIMAC core and QUM rim composition; type [3] spinels occur as isolated grains within the matrix and are dominantly QUM in composition but can have a TIMAC core. Atoll spinels are observed in type [2] and type [3] spinels with magnetite rims. The compositions of the spinels are identical to trend T1 spinels from Wesselton. However; they are unlike spinels from Smeaton 169 kimberlite which is also from the Fort à la Corne field which indicates kimberlite within the same kimberlite field may not have the same source.

The eruption was shallow and excavated Mannville sandstones, Paleozoic limestone and any Colorado mudstone if present. The eruption style was probably dry-phreatomagmatic. This is supported by the shallow bowl shape of the kimberlite body with a depth to width ratio of 1:5.

The C29/30 kimberlite is similar to other Fort à la Corne kimberlites by textural and mineralogical comparison.

This study assessed if a permeable reactive barrier (PRB) could be used to reduce sulphate and metal concentrations of Hogarth pit lake, a sulphite-toxic (up to 2,000 mg/L) pit lake at the former Steep Rock iron mine site in Atikokan, Ontario.  Both batch reactor and flow-through reactor experiments were performed to simulate a PRB at the bench-scale in order to assess the sulphate reducing capacity of different types of organic matter.

Batch reactor experiments were run using three different treatments to promote bacterial sulphate reduction in order to lower sulphate concentrations in water from the pit lake.  Treatment 1 contained organic matter, creek sediment (sulphate reducing bacteria source), carbonate rock (acid neutralizing agent) and glacial till (non-reactive medium).  Treatments 2 and 3 were similar to treatment 1, except that treatment 2 did not include creek sediment and treatment 3 contained molasses as a nutrient.  Treatment 1 with horse manure and wood chips as the organic source resulted in >99% reduction in sulphate concentration, combined with increases in pH and bicarbonate levels, reduced redox and decreased metal concentrations.  Bacterial sulphate reduction was also initiated with Treatment 2, although did not occur as quickly as treatment 1.  The results of treatment 3 with molasses showed that no sulphate reduction occurred in the batch reactors.  Based on these results, treatment 1 was selected for the flow-through experiment to simulate a PRB at a laboratory scale.

Flow-through reactor columns were run in duplicate and filled to create different reaction chambers that contained mixtures of treatment 1.  The most effective sulphate-reducing flow-through reactors consisted of two reaction chambers separated by silica sand, which resulted in an overall sulphate reduction average of 46% and 49%.  In comparison, all other flow-through reactors achieved a 39% reduction in sulphate concentrations.  Sulphate reducing bacteria activity was evident after three weeks with reductions in redox values and sulphate concentrations and increases in bicarbonate and pH levels.  Results of flow-through reactor 1, reduced sulphate concentrations to <300 mg/L between weeks 3 and 5, and had a gradual increase for the remainder of the experiment to around 1000 mg/L.  Results of flow through reactor 5, showed a decrease in sulphate concentration to <700 mg/L between weeks 3 and 8 before also increasing to around 1000 mg/L for the rest of the experiment.  All other reactors generally decreased to 900-1000 mg/L after 2 weeks and remained around 1000 mg/L between weeks 3 and 20.

Sulphate concentration in water from the adjacent Caland pit lake, has a sulphate concentration of <300 mg/L, and a previous study at the site concluded that a treatment system which consisted of a PRB flowing into a constructed wetland has the potential to reduce elevated sulphate levels in Hogarth pit lake.  However, the flow-through experiments show that the residence time is a limiting factor in the life span of a PRB.  Also, it is possible that sulphide precipitation is limited by the availability of divalent metals, in particular Fe²⁺.

A copy of the thesis can be downloaded here

The Angel Hill Gold Zone of the West Cedartree Gold Project has been exposed over 300 meters along the internal contact of ultramafic and gabbroic rocks within the Kakagi Sill. The sill lies within the Kakagi-Rowan Lakes greenstone belt and has intruded the mafic metavolcanic rocks of the Snake Bay Formation and the felsic to intermediate metavolcanic rocks of the Emm Bay Formation. The Snake Bay Formation consists of pillowed and massive basalts and fine-grained tuffs. The Emm Bay Formation stratigraphically overlies the Snake Bay Formation and consists of tuffs and tuff breccias. Trace element geochemistry and primitive mantle normalised plots suggest that both the rocks of the Kakagi Sill and the Snake Bay Formation are comprised of metasomatsed island arc tholeiite basalts whereas the rocks of the Emm Bay Formation are characterised of a back island arc affinity.

The Angel Hill Gold Zone occurs as extensive carbonate and quartz flooding within a zone of brittle deformation termed the master fault. A distinguishing feature of the gold zone is the presence of extensive fuchsite alteration forming large mats up to 20 meters wide. Mineralization in the Angel Hill Gold Zone consists of free gold and sylvanite occurring as inclusions within and rimming pyrite grains, as well as precipitated along small fractures in quartz. Associated mineralization includes pyrite as well as galena and sphalerite. Textural relationships and stable isotope analyses of carbonate (δ¹⁸O 13.6 to 17.9 €), quartz (δ¹⁸O 8.8 to 13.1 €), pyrite (δ³⁴S -0.8 to 1.0 €), sphalerite (δ³⁴S 1.3 to 5.4 €), and galena (δ³⁴S 5.9 to 7.3 €) suggest multiple episodes of brittle deformation and fluid influx within a protracted lode gold system. The combination alteration assemblages and stable isotope characteristics suggest that the Angel Hill Gold Zone formed as a result of listwanite metasomatism with input of fluids from both magmatic and metamorphic sources. These fluids propagated as a result of the brittle faulting that occurred due to a competency contrast between the ultramafic footwall and the gabbro hangingwall during regional deformation.

A copy of the thesis can be downloaded here

Pit lakes are often a planned part of an open pit mine closure where the excavations are expected to flood and water quality is not an issue. Common environmental issues regarding pit lakes include their rebound rate, hydrodynamic behaviour and water quality. The water quality of pit lakes can be influenced by their hydrodynamics, for example overturn in a holomictic lake can transport dissolved oxygen down to submerged tailing resulting in the production of acid mine waters if sulphide minerals are present, or the unexpected overturn of a meromictic pit lake can bring stagnant, dissolved metal laden waters to surface that may be toxic to aquatic life. Where water quality is of concern and pit lakes outflow into adjacent watersheds their behaviour can determine if noxious material will be brought to the surface and released. At the former Steep Rock Iron Mines property near Atikokan, Ontario, three pit lakes are currently flooding and will eventually join to form a super pit lake before they outflow into the West Arm and subsequently Seine River system. Previous studies on two of the pit lakes, Caland and Hogarth, have shown that the pit lakes are meromictic and holomictic, respectively, and that both have elevated sulphate concentrations. The aim of this research was to: i) evaluate existing rebound models by modeling rebound and assessing which parameters exert the greatest influence on the rebound rate; and, ii) develop hydrodynamic models of Caland and Hogarth pit lakes to assess if their current limnology will change as rebound continues and they outflow into the West Arm.

Rebound models are constructed using two approaches and compared to the Ontario Ministry of Natural Resources Regional Engineering model that accurately predicted water levels to 2011. The first rebound modeling approach uses two curves to model the stage-volume relationships, a hypsometric curve and a surface area versus elevation curve. The second approach fits an exponential curve to measured water elevations and then future water elevations are forecasted by extrapolation. Rebound Model 2B constructed following the first approach matched measured water elevations best for the two pit lakes and predicts 2010 measured water elevations better than the Regional Engineering model. Model 2B predicts that Caland will flow into Hogarth in 2070 and that the new Steep Rock pit lake will outflow into the West Arm in 2087, 18 years longer than predictions made by the Regional Engineering model. Based on the water balance parameter sensitivity analysis, the difference between this study's predictions and those of the Regional Engineering model is the result of different pit volume calculation methods. In this study's rebound models the stage-volume relationships for Hogarth are more accurate than for Caland, suggesting that in future work, at minimum, linear interpolation should be used to define the volume in Caland pit lake.

This study is the first to model the hydrodynamics of Caland and Hogarth pit lakes. The Dynamic Reservoir Simulation Model (DYRESM) was used to: i) assess if it can accurately model the current pit lake conditions; and, ii) model the future conditions in Caland and Hogarth for when the pit lakes join and when they outflow to the West Arm. The model salinities are discussed to assess the future toxicity of the pit lakes. DYRESM simulations of current conditions accurately portray the observed limnological characteristics of Caland and Hogarth pit lakes, including: i) that Caland is meromictic and has a lower salinity relative to Hogarth; and, ii) that Hogarth develops a temporary meromix. Simulations of when the two pits join indicate that the freshwater lens in Caland will be maintained, but is thinner, and that Hogarth develops a meromix, which is maintained throughout the simulations. Simulations of when the pit lakes outflow into the West Arm indicate that Caland will maintained its upper freshwater lens and that a fresh water lens is only briefly present in Hogarth. In most cases, variations of the simulations for current and future pit lake conditions, including additional inflows, alteration of the inflow salinities, and the use of a slower rebound rate to define the DYRESM water balance, only produced minor changes in the simulation.

A linear trend between sulphate concentrations and salinity exists for water samples from Caland and Hogarth. Based on this trend, the DYRESM salinity profiles suggest that the waters that outflow from Caland into Hogarth will have sulphate concentrations ranging from 0 mg/L to 100 mg/L and that waters that outflow from Hogarth will have sulphate concentrations ranging from 1700 mg/L to 1900 mg/L. In general, the sulphate concentrations in Caland are below maximum acceptable limit of all water quality standards while those in Hogarth exceed all water quality standards. These results suggest that the waters that outflow from the pit lakes will be toxic.

DYRESM can be used to simulate the future hydrodynamics of Caland and Hogarth pit lakes, however, future studies and field investigations should address some of the areas of uncertainty in the DYRESM simulations for Caland and Hogarth pit lakes, including constraining seep and groundwater volumes and chemistry, on site meteorological monitoring and measurement of the light extinction coefficient.

A copy of the thesis can be downloaded here

The Hamlin Lake area is located approximately 120km southwest of Thunder Bay, Ontario, in the Shebandowan Greenstone Belt of the Wawa Subprovince in the Superior Province. The area has been explored for its copper and gold mineralization for more than 50 years, but has only recently been treated as aniron-oxide copper gold (IOCG) occurrence. The aim of this study was to characterize the alteration at the occurrence through space and time, and to relate this paragenesis to the formation of mineralization. Localized field mapping and re-logging of drill core established several relationships between styles of alteration. Rocks were examined in hand specimen and thin section, and minerals were examined with scanning electron microscope (SEM) to identify mineral assemblages and associations. Consistent variations in space could not be mapped, so textural relationships were used to relate the timing between six styles of alteration and the local brecciation that hosts the potential ore. These are: (1) sodic, (2) early potassic, (3) calcic(-iron), (4) late potassic, (5) carbonate, and (6) silicic.

A copy of the thesis can be downloaded here.