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Gold metallogeny of the southern Swayze Area, Abitibi Greenstone Belt
No full textUnderstanding ore forming processes and their control on mineralization is essential for the proper classification of Archean, and also younger, Au deposits and mineral exploration success. This study evaluates Archean Au-forming processes using examples across the Superior Province (Canada), with an emphasis on the Swayze area in the Abitibi greenstone belt. It combines detailed field mapping with various discriminants (e.g., in-situ stable isotopes, whole rock and trace-element geochemistry, LA-ICP-MS elemental mapping and chemistry of native gold) to differentiate between orogenic and intrusion-related Au deposits. Based on previous work and newly generated data on 44 deposits, the dataset suggests that Ag, Te and Hg are the only metals consistently associated with Au across different deposit types. Although these metals represent universal elemental vectors for Au exploration, other criteria such as rock and mineral textures, timing of Au mineralization, stable isotope data, and bulk geochemistry must be used to differentiate between Au-deposit types. An important finding is the recognition of a distinct subset of intrusion-related Archean deposits related to sanukitoid-type magmatism. These deposits, generally younger than 2690 Ma, predate shearing and are characterized by Te and Hg elemental associations, relatively high fO2, and δ34S ≤ -5‰. They differ from other intrusion related deposits in terms of their timing and geochemistry and, thus, require a different exploration strategy.
Of importance to both academia and industry is the origin of late-stage high-grade Au zones in many deposits. This study suggests such zones result from coupled dissolution-reprecipitation of Au-bearing sulfides and generation of polymetallic Au melts and/or Au nanoparticles, which aggregate as coarse native gold. Both of the processes can elegantly explain ultra high-grade gold zones and are widely applicable to many Au deposits formed throughout Earth’s history
The city as a living museum: reimagining the architecture of industrial monuments through psychogeography and collective memory in Nelson, British Columbia
No full textContemporary development is often
designed within prescribed metrics of cost
and performance ratios - perhaps with some
consideration for the programmatic utility and
outward presentation of the building - though
rarely does it reflect the past history of the
site on which it occupies. It is not common
for a new development to seek to ascertain the
collective subconscious that inhabits the echoing
vestiges of its long-established location, one of
monumental importance to the city it markedly
takes its place within. Albeit a global phenomenon
of modern practice in design, a specificity of
locale, programmatic intent, and architectural
premise are identified within this thesis as an
exemplary study of this proposed rethinking of
development - through Guy Debord’s Dérive.
Any city to undertake this process would require
its own depth and breadth of understanding
critical to its particular genius loci to materialize a
renewed condition of its neglected monuments.
Through a collection of research and
design - influenced by the Situationists (the
Dérive), and urban theorists including Aldo
Rossi, Kevin Lynch, and Christine Boyer - the
city of Nelson, British Columbia will be analyzed
through the frameworks of monumentality,
collective memory, and psychogeography to
revitalize abandoned industrial monuments as
the initial movement for the city to be perceived
and experienced as a ‘living museum’ of historic
sites, and stories. Many heritage buildings have
been preserved (to various degrees) largely
within the downtown core of the city, however
the precursor industrial monuments have not
fared as well against the various conditions of
time in an evolving city. As the catalyst for the founding of Nelson, primary industries and
historic transportation routes long served as the
backbone of all development, yet they are the
least respected in terms of their heritage value on
the immense sites they occupied. This makes the
abandoned industrial monuments of the city the
largest gaps in the urban fabric, and prime areas
for a conception of recovery, and adaptation, to
the contemporary dilemma of land utilization.
A total of five historic ‘monuments’
throughout the city have been examined and
architecturally illustrated anew as the first in
a series of alternate proposals for an episodic
rejuvenation of the urban landscape. Each
of these sites has a long history of industrial
importance in Nelson and have since fallen into
disuse. Establishing them as core community
spaces with programs both reflective of their
collective histories, and of relevant contemporary
use, will serve not just to revitalize the individual
monuments, but further goals to stimulate future
holistic development in neighbouring areas.
While the five locations do not have a unifying
design style or physical linkage (due to the nature
of reflecting their unique origins and memories),
they each have specific histories, including
architectural narratives, and are all connected
via the drifting perceptions of the urban dweller
through the method of the Dérive. By reestablishing influential monuments of the city
into public spaces with a concentrated collective
memory (as well as individual experience), and
connecting them with relevant transportation,
significant historic places will be made accessible
to the community, further revealing the unique
conditions and stories that allowed for the urban
form of Nelson to come into being
Potential drought-driven metal(loid) release in Junction Creek: effects of legacy contamination and the impacts of lime treatment
Get PDFAcid mine drainage (AMD) is a serious environmental problem at legacy and active mine sites
around the world. Climate associated drought and rewetting events can increase the severity of
AMD impacts through oxidation and release of stored metal(loid)s and acidity from
contaminated sediments. The area surrounding Sudbury, Ontario, with its massive mining and
smelting complexes, appears especially vulnerable to such drought-driven effects. I used a paired
subwatershed approach to assess the impact of drought-rewetting cycles in two subwatersheds of
Junction Creek, a heavily contaminated system flowing through the centre of Sudbury. For this
study I chose the Frood tributary which contains a large mine site and waste rock storage area, as
well as the less contaminated Maley tributary as a reference site. Laboratory drying and rewetting experiments with sediment-cores collected from the Nickledale wetland in the Frood
branch surprisingly showed no post-drought re-acidification. However, highest concentrations of
many metal(loid)s were observed in the longest (60-day) drought treatment, suggesting a drought
effect may still occur. Pre-drought lime treatments showed reduced concentrations of many
metal(loid)s in-solution following re-wetting. However, sediment metal(loid) concentrations
suggest that liming applications may cause release of some metal(loid)s through ion exchange
processes. Analysis of available long-term monitoring (2004-2020) data showed annual fluxes in
metal(loid) concentrations in both subwatersheds, but the expected strong seasonality of the
metal export was best observed at the reference Maley site rather than at the industrial Frood site.
Additionally, it was observed that surface water As concentrations were in fact highest at the
reference site. Overall, this study provides preliminary data demonstrating that the remedial work
at the mine impacted site has reduced the vulnerability of this subwatershed to the climate-driven
impacts.Master of Science (MSc) in Biolog
The development of perceptual-attentional processes of children in the recognition of basic emotional facial expressions: an eye-tracking study
Get PDFThe current study investigated the role of facial areas in the recognition of six basic emotions
(happiness, sadness, fear, anger, surprise and disgust) as well as the perceptual and attentional
development of emotion recognition in school aged children. Participants viewed images of
emotional facial expressions at various intensities and were asked to identify which emotion was
being expressed while their eye movements were being tracked. Happiness was the easiest
emotion to recognize, followed by anger then sadness for all children. The hardest emotions to
recognize were surprise (5-year-olds) and fear (10-year-olds). Surprise was also the only emotion
for which a difference between age groups occurred. All children spent more time looking at the
eye/brow area for all emotions but anger. Only one relationship between recognition accuracy
and time spent on different areas was found. The results of this study highlight the complexity of
emotion recognition in developing children
Evaluating trust levels of virtual assistants utilizing different communication channels
Get PDFThis thesis compares three channels of communication for virtual assistants; text, voice, and
avatar, in terms of trust elicited from users. Participants played through a series of three escape
rooms alongside the virtual assistant before rating their opinions on an array of attributes,
revealing that the channel does not impact a user’s trust in virtual assistants when all else is
equal. Significant differences were found in areas of time spent, difficulty, and usefulness of the
assistant for participants with and without digital escape room experience, and a strong
correlation was found between trust and usefulness of virtual assistants when they are text only.Master of Science (MSc) in Computational Science
Architecture and affordance: a data driven and computational approach to the architectural analysis and design of buildings using affordance as a model of typology
Get PDFISpace syntax has long been
used as a spatial analysis tool to
graphically represent the relationships and connections between spaces. This has been used to promising
effect in the past to compare buildings of a similar typology in order
to better understand them. We can use
the framework of space syntax and
introduce affordances to gain a better understanding of how affordances
of access, natural light, sound, and
activity congregate in building typology. By building a digital sensor
array and conducting an analysis of
a particular building typology, we
can start to find optimal patterns of
affordance which exist within living
buildings. The typology I am looking at
for this thesis is the United Churches of Sudbury. Sacred space is a phenomenologically dense and interesting typology which lends itself to
generating interesting data. United
Churches as a typology also have a
philosophy of shared multi-use space
which lends itself well to this more
generalized approach to understanding program through affordances.
In this thesis, I look at four
different case studies of United Churches, one to understand what
makes a United Church, and three others as examples of typology and subjects for collecting data. The aim of
this work is to use this data to develop a set of computational design
tools that will eventually be used to
suggest a possible design for a United Church on the site of Larchwood
Memorial United Church in Dowling.
Aside from site analysis, there
are two parts to this affordance
based process. Just like how Gibson distinguishes between affordances and the invariant properties of
objects, I take stock of affordances
through a set of affordance graphs
and tables of relevant data from each
of my case studies in Sudbury. I also look at the design solutions such
as furnishings and building openings
which these churches used to satisfy
those affordances and document them
in the from of a pattern language.
Using the affordance data, I
find common patterns of design and
layout for a given typology. These
patterns of affordance can then be
used with a generative algorithm to
generate a schematic design. In this
thesis, I will present a number of
schematic designs and explore the
range of outcomes, limitations, and
areas for improvement that you can
expect from this approach to generative design.
A final schematic design can
then be matched with examples of vernacular objects and strategies found
and documented through the pattern
language of sacred space. Using data
that I have collected about openings
and furnishings in the case studies,
it becomes possible to automatically populate these schematic designs
with objects to complete the design.
This thesis will detail this process
and the theory behind it
A fluid-flow modeling approach for predictive mapping of orogenic gold mineralization in the Malartic camp, Canada
No full textOrogenic gold deposits are structurally controlled and commonly formed in the transition zone
between brittle and ductile crustal domains. Formation of disseminated or localized gold
mineralization involves structural features (e.g., fault zones, fold hinges), contrasts in physical
properties (e.g., rock competency and permeability, lithostatic and hydrostatic pressure,
temperature) or chemical variability (e.g., rock chemistry, fluid composition). Orogenic gold
deposits form in convergent tectonic settings, at crustal depths of between 3 and 18 km, from
the Paleoarchean to the present. However, the goal of this study is just to investigate the
hydrothermal properties of a model and predict the influence of deformation zones, rock types
and the associated physical parameters on fluid-flow associated with orogenic gold systems,
and subsequently develop new feature-engineered layers for mineral exploration purpose.
Open-source numerical modeling software OpenGeoSys, has been used to reconstruct the major
fault network in the Malartic mining district, in an area 19.7 km long and 7.3 km wide. This
model can compare thermal convection fluid flow with deformation induced fluid flow. Results
of numerical simulations conducted in OpenGeoSys and relative calculations from different
physical parameters along faults or intrusive contacts explain the existence of a spatial
association with the distribution of orogenic gold prospects and mines in the Malartic camp.
Results of Weight of Evidence demonstrate that the incorporation of faults in 3D finite element
models for coupled fluid and heat transport simulations has the potential of indicating favorable
areas for gold mineralization in a 3D space, which can ultimately lead to new mineral
discoveries
Open pit-underground mining options and transitions planning: a mathematical programming framework for optimal resource extraction evaluation
No full textNear-surface mineral deposits that extend to great depths are amenable to both open pit mining and/or underground mining. The strategic planning of such mineral deposits often leads
to several variations of open pit-underground (OP-UG) mining option(s) and transitions including (a) independent open pit (OP) mining, (b) independent underground (UG) mining,
(c) simultaneous open pit and underground (OPUG) mining, (d) sequential OPUG mining,
and (e) combinations of simultaneous and sequential OPUG mining. Notable limitations to
recent developments in the OP-UG mining options and transitions optimization problem includes one or more of the following: a) lack of rigorous mining optimization approach, b)
lack of solution optimality assessment, c) lack of geotechnical consideration for the mining
options and transition zones, d) lack of consideration of exhaustive variables for essential
UG mining complexes, and e) non-comprehensiveness and inefficiency of the implementation models.
The main research objectives are 1) propose an optimization technique for OP-UG mining
options and transitions planning, and 2) develop, implement and verify a theoretical optimization framework based on Mixed Integer Linear Programming (MILP) model to determine:
a) the most suitable mining option(s) to exploit an orebody; b) the position of the required
crown pillar, time and order of development of primary and secondary accesses and main
ventilation opening, and the schedule of geotechnical support of the secondary development
accesses and stopes if UG mining option is considered; and c) the ore and waste extraction
schedules that maximizes the net present value (NPV) of the mining project.
MATLAB programming platform was chosen for the MILP formulation implementation and
a large-scale optimization solver, IBM ILOG CPLEX, was used for this research. The MILP
formulation was tested and implemented with an experimental copper dataset and two real
gold deposit case studies. The first case study verified the appropriateness of the optimization technique and strategies used in the MILP framework for open pit-underground mining options and transitions planning. The second and third case studies are implemented with stockpile management and multiple essential underground infrastructures to enhance practicality and rigor of the MILP model. The third case study was additionally evaluated with industry standard software, Whittle, and the results compared to that from the MILP model.
The MILP model scheduled the deposit with combined sequential and simultaneous OPUG
mining over 8 years mine life while Whittle scheduled the deposit for OP mining over a mine
life of 20 years. The NPV generated by the MILP model was 2.31 billion, representing about 42.4%
loss in financial benefits. The stripping ratio from Whittle OP mining was 2.79 compared to
0.34 from MILP model for the OPUG mining. Analysis of the results showed that, the MILP
model significantly avoids the mining of excessive waste to uncover mineralized material
by switching from OP to UG mining option. This MILP framework implementation for extraction of deep-seated near-surface deposits demonstrate potential value to a mining project at the prefeasibility stage when the global mining options decisions are guided by a rigorous optimization process. The MILP framework do not evaluate the impact of varying crown pillar dimensions on the mining options.Doctor of Philosophy (Ph.D.) in Natural Resources Engineerin
Post apocalypse of the future: architectural potentiality in a changing world
No full textDue to the looming Climate Change threat of anthropogenic origins, the prospects of
humanity’s place in the world are uncertain. Conceiving an architectural response that
would serve as the basis for humanity’s survival under these new climatic conditions
becomes a question of adaptability and potentiality. As wrought out by Climate Change’s
effect on an environment and its people over time, the immense gamut of possibilities
implies that the potential conditions a society might find itself in are undoubtedly vast.
Therefore, it is insufficient to conceive an architectural response that satisfies only one of
those conditions. This thesis creates a framework that may generate potential architectural
responses in dialogue with Climate Change. It maps out potentiality onto a site and
discovers the architectural responses embedded within without being prophetic. To do so,
criteria are first established.
1 - Developing an understanding of the temporal aspect of Climate Change and how
something might need to respond.
2 - Involve a certain degree of speculation, so as to allow room for change and response.
3 - Outline an understanding of the milieu as an extension of the idea of site.
4 - As an extension of speculation, the inclusion of filmic apocalyptic science fiction films
provide a sense of the current thought regarding Climate Change and its impacts on society
and the world.
Combining the aforementioned criteria, this thesis explores the potential of Climate
Change to drastically change the world, and subsequently, a milieu, over time. This project
seeks to examine the many modes of transition that occur during an apocalyptic process
and how a subject might respond. It is more or less impossible to quantify a “good” or
“bad” response. One would be remiss to imply that a set solution can be generated. Even
simply using the word ‘solution’ would suggest an idea of finality, binarity, right or wrong,
or up or down. Instead, it is essential that a flexible range of architectural responses, in
response to a flexible gamut of points of perturbations, times, responses, lines, fields, etc.,
is developed during the mapping of potentiality that this project entails. Whatever this
means is indeed left to interpretation
A new model for an old camp: the enigmatic Ag-Co-Ni-As-Bi mineralization of Cobalt, Ontario
No full textThe recent emergence of Co as a critical metal used in a variety of high-technology
industries has refocused exploration at Cobalt, Ontario. This district represents an unusual ore
deposit-type termed the five-element (Ag-Ni-Co-As-Bi) assemblage and was important
historically as Canada’s former premier Ag producer at over 460 Moz (1904-1989). This study
applies a sophisticated analytical protocol consisting of whole rock analysis, petrography, and insitu mineral analyses (SEM-EDS, LA-ICP-MS) to a sample suite with spatial coverage across the
district. These methods constrain geological controls on regional metal distribution, the sequence
of alteration and mineralization, and the physiochemical evolution of the system. An updated
genetic model for the mineralization involves the veins representing a district-scale
homogeneous hydrothermal-metal melt system driven by contact metamorphism and partial
melting of pre-existing sulfides in underlying Archean basement rocks. This model enhances
understanding of deposit formation and offers refined geochemical vectors to aid ongoing
exploration efforts