Tesi sul tema "Kalgoorlie"

Because of the peculiar characteristics of the Kalgoorlie goldfield's environment and geology, its metallurgy developed largely independently of other major gold mining centres. Its engineers and metallurgists borrowed ideas from a variety of sources to develop new equipment such as the filter press and the tube mill and new procedures such as the 'Australian method' of treating ores by fine crushing, sliming and filtration. By 1905 Kalgoorlie was the leading centre for gold metallurgical development in the world, and equipment and techniques developed there were adopted with remarkable rapidity around the world. From 1910 the impetus for innovation in Kalgoorlie declined and further improvements were limited to those gained by increased scale of production and rationalisation through company amalgamations. This thesis focuses on the evolution of the metallurgical changes which took place in the very productive mines on the Kalgoorlie Golden Mile during the twenty years from 1895 in response to problems in ore treatment and the need to reduce production costs to enable lower grades of ore to be processed. The principal developments were: the early adoption of the cyanide process; the introduction of the filter press to enable rich slimes to be cyanided; the temporary expedient of treating very rich sulphide ores and concentrates by smelting; the development of the two main processes for treating the sulphotelluride ore, the dry crush and roast process and the bromocyanide or Diehl process; and the introduction of the automatic, continuous flow, vacuum filter. The inter-relationship between international technological transfer and increased local inventiveness, stimulated by the rapid changes in technology, is the main theme explored in the thesis. Others include the opportunities and limitations experienced by Australian metallurgical inventers in the 1900s and the occupational hazards and pollution problems associated with the new technologies. The history of Kalgoorlie metallurgy reflects the difficulties of developing on a rational basis foreign-owned mines that were acquired largely for speculative purposes, and of maintaining a technological lead in an industry which was subjected to long term fluctuations in profitability and hence lack of continuity in process development.

The purpose of this study was to evaluate an instrument designed to assess the influence of the media on opinions regarding the one percent motorcycle clubs in Kalgoorlie-Boulder, establishing whether the media had incited a moral panic towards the clubs. The concept of the moral panic, developed by Stanley Cohen iii ( 1972), is the widespread fear towards a social group by events that are overrepresented and exaggerated. Exploring the concept of a moral panic towards the one percent sub-culture, this study compares the perceptions from two groups of non-members in Kalgoorlie-Boulder. One group of participants had interacted with club members (n =13); the other had no direct contact with club members and identified themselves as basing their opinions towards the clubs on information from the media (n =13). It was hypothesised that the two patticipant groups would differ on their opinions regarding the clubs' autonomy, brotherhood, the righteous biker model, and the perceived image of one percent members. Participants were requested to complete the Perception of the One Percent Motorcycle Sub-culture Questionnaire. Quantitative data were analysed using the nonparametric Mann-Whitney U test. The findings suggest little differences between the groups, indicating a moral panic towards one percent motorcycle clubs has not been identified by the instrument. Recommendations for improvement in the research design for a comprehensive study include modification to sampling techniques, Likert scales and analysis techniques. Further research is required to validate the present findings.

The historiography of Australian racism has principally "blamed" the labour movement for the existence of the White Australia policy and racist responses to the presence of migrant workers. This study argues that the motivations behind ruling class agitation for the White Australia policy have never been satisfactorily analysed. To address this omission, the role of the Returned and Services League of Australia (RSL) in race relations is examined. As an elite-dominated, cross-class organisation with links to every section of society, it is argued that the RSL was a significant agitator for migrant exclusion and white unity in the interwar period. The thesis employs case studies, oral history and qualitative assessment of various written sources, such as newspapers, archival records and secondary material, in order to plot the dynamics of racist ideology in two major mining centres in the interwar period. The results suggest that, although labour organisations were influenced by racist ideas and frequently protested against the presence of migrant workers, it was also true that mining employers had a material interest in sowing racial division in the workplaces they controlled. The study concludes that labour movement responses to migrant labour incorporated a range of different strategies, from demands for racist exclusion to moves towards international solidarity. It also reveals examples of local and migrant workers living, working, playing and striking together in ways that contradict the dominant view of perpetual tension between workers of different nationalities. Lastly, the case studies demonstrate that local employers actively encouraged racial division in the workplace as a bulwark against industrial militancy.

Solar power tower (SPT) plants with thermal energy storage (TES) provide great opportunities on the utility-scale; becoming a viable option for areas with moderate to high direct solar availability. The absence of commercial SPTs in Australia, together with the need to increase renewable energy capacity, raises the importance of proving it viable and beneficial. There is an apparent research gap, specifically, into the feasibility of a grid connected SPT with molten salt storage system for the Goldfields city, which this research explores. In this dissertation, solar power tower with storage systems are reviewed to facilitate the research. The System Advisor Model (SAM) base case 104 MW SPT, with the performance advancement that (14 hours) molten salt storage adds, introduces the capability of replacing conventional power plants, generate reliable base load or demand following electricity into the SWIS power grid and create jobs. Kalgoorlie-Boulder, with its excellent solar resource, infrastructure, local economy and SWIS grid connection enables this solar thermal power system to be considered appropriate. The research methodology presents the procedure and limitations in the modeling of the system, and the sensitivity analysis. The estimated performance of certain SPT with molten salt TES designs (similar to Crescent Dunes SPT plant) show that it could generate all of the city’s electricity demand (excluding the mine sites), and still feed in electricity to the grid. The benefits from grid connection come in the form of capacity credits and renewable energy certificates. These are required to form a PPA, as the estimated LCOE is above the fossil fuel range (although in line with current SPTs with storage). Taking advantage of Government policies and incentives from the gird, together with the system costs (explicitly, heliostat field) predicted reduction, the gap will close, improving economic viability and enhancing its feasibility.

The Kalgoorlie Terrane of the Yilgarn Craton, Western Australia, containing about 60% (~11 Mt) of the world’s known komatiite-hosted nickel sulphide resources, is the world’s best studied and economically most important province for this mineral deposit type. Although increasingly mature in terms of nickel exploration, the Kalgoorlie Terrane is believed to contain significant additional undiscovered nickel endowment. Using the data-rich Kalgoorlie Terrane, this thesis develops a benchmark methodology that combines geological knowledge with spatial analysis and mathematical-statistical methods to estimate undiscovered nickel resources.In the proposed methodology, nickel sulphide deposits are considered realisations of stochastic mineralisation processes and are analysed within the following framework. Komatiites in the Kalgoorlie Terrane constitute the full sample space or the permissive tract. Disjoint, naturally bound individual komatiite bodies that make up the sample space are used as the spatial analysis units. Some komatiite bodies within the sample space contain nickel sulphide deposits (mineralised) and others do not (unmineralised). In this study, the most explored mineralised komatiite bodies constitute local control areas against which nickel resources in the less explored komatiite bodies can be assessed. The concept of local control areas is analogous to the concept of global control areas which are well explored parts of permissive areas for particular deposit types worldwide.Spatial point pattern analyses showed that the spatial distribution of mineralised komatiite bodies within the sample space is clustered. In contrast, nickel sulphide deposits in individual komatiite bodies are either randomly distributed or dispersed, and not clustered. This absence of deposit clustering within individual komatiite bodies indicates that the intensity of the deposit pattern of each komatiite body may be adequately expressed as deposit density (number of deposits per km[superscript]2). In global quantitative resource assessments, regression analysis of the well established power law relationship between deposit density and size of global control areas provides a robust method for estimating the number of deposits.In this study a power law relationship reminiscent of that in global models was found between the sizes of control areas and deposit density. In addition, this study establishes another power law relationship between nickel endowment density (nickel metal per km[superscript]2) and the sizes of control areas. Deposit and endowment density regression models based on the two power laws suggested that, respectively, 59 to 210 (mean 114) nickel sulphide deposits and 3.0 to 10.0 Mt (mean 5.5 Mt) nickel metal remained undiscovered in demonstrably mineralised komatiite bodies within the Kalgoorlie Terrane. More emphasis is placed on endowment density which may be more intrinsic to the Kalgoorlie Terrane than deposit density because deposit counts are confounded by definitional ambiguities emanating from orebody complexities. Thus the spatial pattern of mineral deposits may not coincide with the spatial pattern of mineral endowment as demonstrated by spatial centrographic analyses in this study.To estimate the amount of undiscovered nickel metal in the entire Kalgoorlie Terrane and not just in the demonstrably mineralised komatiite bodies, Zipf’s law was applied. According to Zipf’s law, the size of the largest deposit is twice the size of the second, thrice the size of the third, four times the fourth, and so on. Based on the currently known size of Mt. Keith deposit, the largest nickel sulphide deposit in the Kalgoorlie Terrane, Zipf’s law indicates that the terrane is nearly mature in terms of nickel exploration and contains only about 3.0 Mt nickel metal in undiscovered resources. The collective implication of the regression and Zipf’s law estimates is that in the Kalgoorlie Terrane, no significant nickel resources are likely to be contained in the known komatiites that are presently not demonstrably mineralised. However if, as widely speculated, the actual size of Mt. Keith deposit is about twice the currently known size, Zipf’s law predicts 10.0 Mt nickel metal in undiscovered nickel endowment for the Kalgoorlie Terrane. The additional 7.0 Mt undiscovered nickel metal endowment is attributed to opening up of a new exploration search space through deeper resource delineation, within an otherwise nearly mature terrane.

Nontypeable Haemophilus influenzae (NTHi), Streptococcus pneumoniae and Moraxella catarrhalis are common bacterial agents of otitis media which is a major cause of morbidity in young children. Mucosal immune responses are an integral part of the immune defense against middle ear infection and it is known that certain populations, including Australian Aboriginal children, are highly susceptible to disease. The current study focussed on the development of the mucosal immunity to the three bacterial pathogens in Aboriginal and non-Aboriginal children from birth to two years of age, living in the Kalgoorlie-Boulder region of Western Australia. Salivary and breast milk IgA levels were measured by the enzyme Linked immunosorbent assay. The measured IgA levels, combined with socio-economic, demographic and bacteriological data were analyzed statistically to determine the influential factors on the mucosal IgA response in these children over time. This study found that each antigen-specific IgA examined followed a distinct ontogeny pattern and IgA responses differed significantly according to age, indigenous status and feeding type. Indoors smoke exposure, maternal smoking, and sibling day care attendance had some impact on salivary IgA levels in the children. However, household crowding and the presence of older siblings had the most significant impact on salivary IgA levels for children of different age groups. These two factors were correlated to increased nasophayrngeal colonization by H. influenzae, S. pneumoniae and M. catarrhalis and colonization status was also found to influence salivary IgA levels in the children. No correlation between maternal breast milk IgA levels and child salivary IgA levels was observed. The results suggest that the degree of exposure to environmental factors rather than immunological deficit is responsible for the observed differences in salivary IgA responses between Aboriginal and non-Aboriginal children and modifying these factors could lead to a reduction in the burden of otitis media experienced by the children. Further studies correlating specific salivary IgA levels to diseases such as otitis media will reveal the role of specific salivary IgA responses in the prevention of infection by respiratory pathogens.

[Truncated abstract] The Neoarchean (2800 to 2600 Ma) Eastern Goldfields Superterrane (EGST) comprises elongated belts of deformed and metamorphosed volcanic and sedimentary rocks intruded by granitoids. The Superterrane is made up of five distinct tectonostratigraphic terranes. From west to east these are the Kalgoorlie, Gindalbie, Kurnalpi, Laverton and Duketon Terranes. The Kalgoorlie Terrane is characterised by 2720 to 2680 Ma marine mafic-ultramafic volcanic successions interlayered with, and overlain by, 2710 to 2660 Ma dominantly trondhjemite-tonalite-dacite (TTD) dacititic volcaniclastic rocks (Black Flag Group). The adjacent Gindalbie and Kurnalpi terranes are characterised by 2720 to 2680 Ma calc-alkaline volcanic successions representing oceanic island arcs. To the west of the EGST, the Youanmi Terrane is characterised by older, dominantly 3000 to 2900 Ma greenstone rocks and complex granitoid batholiths derived from older crustal sources. The southern Kalgoorlie Terrane comprises five elongate NNW-trending tectono-stratigraphic domains. Three principal marine komatiitic to basaltic suites, collectively referred to as the Kambalda Sequence, are present, including the wellpreserved massive to pillowed Lower and Upper Basalt Sequences, separated by the Komatiite Unit, as well as numerous dyke suites. The Lower Basalt Sequence comprises the Woolyeenyer Formation, Lunnon, Wongi, Scotia, Missouri Basalts and Burbanks and Penneshaw Formations, whereas the Upper Basalt Sequence contains the Paringa, Coolgardie, Big Dick, Devon Consols, Bent Tree, and Victorious basalts. ... Instead, the data suggest that discrete PGE-bearing phase (s) fractionated from the basaltic magmas. Such phases could be platinum group minerals (PGM; e.g. laurite) and/or alloys, or discrete PGE-rich nuggets. In summary, data on the three magmatic sequences record decompression melting of three distinct mantle sources: (1) long-term depleted asthenosphere for prevalent depleted tholeiitic and komatiitic basalts, and komatiites; (2) long-term enriched asthenosphere for Paringa Basalts and similarly enriched rocks; and (3) shortterm enriched continental lithospheric mantle (CLM) for HREE and Al-depleted dykes. Some of these rocks were contaminated by TTD-type melts. Taken with the existing geophysical and xenocrystic zircon data, the most straightforward interpretation is eruption of a zoned mantle plume at the margin of rifted continental lithosphere. The Kalgoorlie Terrane extensional basin was subsequently tectonically juxtaposed with the adjacent arc-like Gindalbie and Kurnalpi Terranes at approximately 2660 Ma at the start of orogeny in a Cordilleran-style orogen to form the EGST. Collectively, uncontaminated basalts have Nb/Th of 8-16, compared to 8-12 reported for the Lunnon basalts in a previous study. To a first approximation these asthenosphere melts are complementary to average Archean upper continental crust with Nb/Th =2, consistent with early growth of large volumes of continental crust rather than models of steady progressive growth.

Late in 1996, Kalgoorlie College and the Western Australian School of Mines in Western Australia were merged to form an expanded campus of Curtin University, based in the state capital City of Perth. This event is examined as an episode of organisation change, with a particular focus on the micro-level experience of the various actors and groups involved in the change episode. The merger took place against a background of multi-level social and institutional change: for the Kalgoorlie-Boulder regional economy, in Australian higher educational policy and in national economic and social policy in response to the impacts of globalisation. These macro-level changes significantly impact upon the change processes at the microlevel, though this impact is often masked by the ‘noise' of surface level debate and conflict. The thesis deploys an interdisciplinary methodology within the theoretical framework of reflexive modernisation to analyse the change episode as an instance of the reflexivity that results from the disruptive effects of globalisation and which uses the frame analysis to explore the conceptual and discursive shifts central to the merger. As the complex and messy merger episode process was played out, three important frames, each of which structured the debate for periods of time, are identified: one that emphasised regional social and economic development, another centred on education for industry and a third based on economic rationalism. Frame analysis is also used to explore the social location and interpretations of the merger. The thesis concludes by advocating the adoption of a more frame reflective approach to organisational change that can address micro-politics of self-reflexivity and the macro-challenges of structural and institutional reflexivity in an era of reflexive modernisation.

In describing the historical development of these two settlements based on mining, this thesis outlines the ways in which the performing arts played a significant role in the evolving social and cultural development of both centres and that mining, especially in the form of the these two goldrushes, was highly influential in the distinctive development of the performing arts in Australia in the second half of the nineteenth century and beyond.

Geologically-constrained inversion of geophysical data is a powerful method for predicting geology beneath cover. The process seeks 3D physical property models that are consistent with the geology and explain measured geophysical responses. The recovered models can guide mineral explorers to prospective host rocks, structures, alteration and mineralisation. This thesis provides a comprehensive analysis of how the University of British Columbia Geophysical Inversion Facility (UBC–GIF) gravity and magnetic inversions can be applied to subsurface mapping and exploration by demonstrating the necessary approach, data types, and typical results. The non-uniqueness of inversion demands that geological information be included. Commonly available geological data, including structural and physical property measurements, mapping, drilling, and 3D interpretations, can be translated into appropriate inversion constraints using tools developed herein. Surface information provides the greatest improvement in the reliability of recovered models; drilling information enhances resolution at depth. The process used to prepare inversions is as important as the geological constraints themselves. Use of a systematic workflow, as developed in this study, minimises any introduced ambiguity. Key steps include defining the problem, preparing the data, setting inversion parameters and developing geological constraints. Once reliable physical property models are recovered they must be interpreted in a geological context. Where alteration and mineralisation occupy significant volumes, the mineralogy associated with the physical properties can be identified; otherwise a lithological classification of the properties can be applied. This approach is used to develop predictive 3D lithological maps from geologically-constrained gravity and magnetic inversions at several scales in the Agnew-Wiluna greenstone belt in Australia’s Yilgarn Craton. These maps indicate a spatial correlation between thick mafic-ultramafic rock packages and gold deposit locations, suggesting a shared structural control. The maps also identify structural geometries and relationships consistent with the published regional tectonic framework. Geophysical inversion provides a framework into which geological and geophysical data sets can be integrated to produce a holistic prediction of the subsurface. The best possible result is one that cannot be dismissed as inconsistent with some piece of geological knowledge. Such a model can only be recovered by including all available geological knowledge using a consistent workflow process.

An extensive network of valleys filled with a distinctive sequence of Tertiary clastic sediments lies buried beneath a Quaternary cover in the Eastern Goldfields region of southwestern Australia. Apart from being weathered in their upper part, the valley-fill sediments are excellently preserved and constitute the most comprehensive record of Cenozoic depositional and erosional events in the region. Locally containing economic concentrations of gold and uranium and forming important groundwater aquifers, good access to the valleys and their fills is provided by open-cut mines and drill core. Formerly referred to as 'palaeochannels', the buried valleys are herein termed 'inset-valleys' to emphasise their subordinate and entrenched position within the bedrock surface of another system of much broader and subtly defined 'primary-valleys'. Within the Kalgoorlie study area, which encompasses the upper to middle reaches of the Roe inset-valley network, the inset-valleys form a fairly coarse textured, sub-dendritic pattern with up to eight orders of tributaries. The inset-valleys have a width-depth ratio of approximately 15, increasing in dimensions with tributary order to a maximum width and depth of about 1.4 km and 75 m, respectively. Most inset-valleys have a symmetric, open V -shaped transverse form with rare structural benches and unpaired terraces forming small steps in the side-walls. In longitudinal section, the insetvalley network displays a smooth, concave-up profile typical of having been reduced by a stream system graded to base-level. Contrary to most previous interpretations, the inset-valleys are temporally and genetically distinct from the primary-valleys in which they occur. The primary-valleys were largely formed by prolonged fluvial erosion of the Yilgarn Craton during the Mesozoic, which contributed to filling of the evolving Bight rift basin between Australia and Antarctica. The inset-valleys, in contrast, were formed by stream rejuvenation following epeirogenic uplift of the Yilgarn Craton interior well after the primary-valleys were established. The cause for epeirogenic uplift of the Yilgarn Craton remains uncertain, but can be tentatively linked to a change in the horizontal stress field resulting from a major plate tectonic re-organisation in the late Middle Eocene (-43 Ma), Climate change and eustatic sea-level fall appear to be incapable of generating valleys of the dimensions and lateral extent exhibited by the inset-valley networks in the Easten Goldfields. In any case, both of these allogenic variables were poorly disposed to fluvial incision during the early Tertiary - the climate being sufficiently warm and humid to support a thick mesothermal rainforest cover, and the shoreline being restricted to the continental shelf, over 500 km distant from the upper reaches of the Roe inset-valley network. Following formation of the primary-valleys and preceding incision of the inset-valleys, there occurred a period of limited fluvial activity which facilitated widespread deep weathering of the Precambrian granitoid and greenstone basement rocks that constitute the bulk of the eastern Yilgarn Craton. This is evidenced by the weak influence of bedrock lithology and structure on the pattern of inset-valley incision and the chemical maturity of the inset-valley fills. In common to all sections of the inset-valley fills examined are three unconformities, the lowermost of which is the inset-valley form. These provide a convenient framework for subdividing the inset-valley fills into two alloformations and an overlying sequence of 'primary-valley fill'. The basal alloformation (AFl), comprises an assemblage of dominantly coarse-grained, fluvially deposited lithofacies whose composition and architecture depend strongly on position within the inset-valley network, and for 'tributary' (~5th-order) inset-valleys, also on the type of underlying bedrock. This allows for the definition of three AFl 'fill-styles'- fill styles I and 2 incorporating the fill of tributary inset-valleys developed over weathered granite and mafic-ultramafic rocks, respectively; and fill-style 3 comprising the fill of trunk inset-valleys. All three fill styles clearly reflect derivation from deeply weathered basement and were deposited in high gradient, low sinuosity bedload channels that occupied the full width of the inset-valley floor, or migrated repeatedly across it destroying all evidence of overbank sedimentation. Channel fills of regularly alternating coarse- and fine-grained strata indicate that stream discharge was strongly cyclic. Alloformation 2 (AF2) by contrast, is dominantly composed of clay-rich lithofacies deposited in a hydrologically fluctuating, wetland environment. Lenses of ferruginous gravel, sourced from both within and outside the 'basin' of deposition, reflect the episodic establishment of fluvial conditions. Weathering and diagenetic overprints are typically extensive, assuming the form of dolomite pods, opaline silica lenses, and abundant ferruginous nodule and mottle structures. Deposition of AFl occurred rapidly in response to an excess of sediment supply affected by a change to a markedly seasonal climate during the middle-late Middle Eocene. Subsequent marine transgressions during the late Middle-Late Eocene invaded the lower reaches of the Eastern Goldfields inset- and primary-valley networks, but did not penetrate for far inland because sediment supply was able to keep pace with the generation of accommodation space. Instead, within the middle,-upper reaches of the inset-valley networks, fluvial deposition continued with the influence of a rising baselevel being transferred upstream as changes in fluvial style. Closely following the Late Eocene sea~level maximum there occurred a major marine regression resulting from the first Cenozoic continental-scale glaciation of Antarctica (Terminal Eocene Event). This rapidly brought the shoreline back to the continental shelf causing widespread erosion within the inset-valleys and removal of any evidence of the marine transgressions from the middle-upper reaches of the Roe inset-valley network. Low sea-levels and a marked cooling of global climate following the Terminal Eocene Event saw the development of cool. dry conditions onshore, transforming the inset-valley floors into a series of wetlands. Deposition of AF2 commenced at a very slow rate in the Early Oligocene and may have continued through to the Early Miocene. Deposition of allofonnations 1 and 2 within the middle-upper reaches of the Roe insetvalley network was, therefore, dominantly controlled by climate and did not result from distant rises in sea-level, as is generally thought to be the case. A second phase of epeirogenic uplift of the Yilgarn Craton occurred in the Middle Miocene bringing the inset-valley fills to their current elevations. However, owing to further reductions in rainfall and fluvial activity, erosion associated with this phase of uplift was slight. Arid to semi-arid conditions prevailed during the Late Miocene-Holocene, resulting in deposition of the primary-valley fill and completion of the Cenozoic succession.

This study investigates two sites within the Roe Palaeodrainage system in the Kalgoorlie Region of Western Australia. Both are located over southward draining tributary palaeochannels that have incised into already deeply weathered Archaean lithologies. The pre-palaeochannel regolith is only partly preserved at Gindalbie due to the site's proximity to the main trunk palaeoriver. However at Kurnalpi, there is extensive preservation of the pre-existing laterite profile beneath the palaeochannel sediments and permits an estimation of the maximum depth of palaeochannel incision: That is 25-30 metres at Kurnalpi; 40-50 metres at Gindalbie; 60-70 metres in the trunk channel. The palaeochannel sediments comprise a basal sand facies that is generally confined to the palaeoriver bed, and a conformable upper clay facies that blankets the entire palaeodrainage valley. The sediments have also been lateritized, resulting in an extensive ferruginization of the upper profile (Fe-induration, Fe-nodules and pisoliths, and mega-mottles), and at least at Gindalbie, a prominent redox front at 18-20 metres depth below which reducing conditions prevail. The sand facies has been palynologically dated by others as Middle to Late Eocene in age, thus constraining the lateritization events to pre and post-Eocene. At Kurnalpi, colluvial/alluvial incision has extensively truncated the upper profile of both the transported and in-situ regolith. This event has occurred after post-Eocene lateritization and appears to be confined to the mid and upper slopes of the catchment area. At both sites gold mineralization is extensive but is confined to the environs of the palaeochannels. At Gindalbie gold is almost exclusively distributed as discrete horizontal horizons within the palaeochannel sediments below the main redox front, with the highest grades located directly above the palaeochannel thalweg. No bedrock mineralization was encountered; and gold distribution appears to be controlled by groundwater regimes/chemistry and host lithology mineralogy. At Kurnalpi Archaean lode-style gold mineralization is spatially associated with supergene gold within both the palaeochannel sediments and the in-situ regolith. The highest gold grades from both regolith profiles are distributed about a vertical plane through the channel thalweg, with placer gold located at the base of the palaeochannel sand facies. All gold mineralization appears to be derived initially from basement lodes and distribution patterns reflect local controls such as bedrock structure, basement lithology, channel morphology and groundwater movement.

The remarkably prodigious gold endowment of the Neoarchaean was controlled by specific characters of the stratigraphy, structural geology, and geochemistry of greenstone belts. This study attempts to synthesise stratigraphic, structural and geochronological data to understand the geology of the Kalgoorlie greenstones, and by representing those data on maps to assess the controls on major gold deposits. Voluminous, previously unavailable regional - scale data sets from exploration and mining provide new insights into the controls on gold deposits in the north Kalgoorlie district of the Eastern Goldfields Province (EGP) in Western Australia. The end of mafic volcanism is constrained by a new U-Pb SHRIMP age determination for the Golden Mile Dolerite at 2685±4 Ma (host to the largest Archaean greenstone gold deposit). This new age determination indicates a possible three million year time gap between the intrusion of the Golden Mile Dolerite (>2681 Ma) and overlying Lakewood dacite volcanics (<2678 Ma), allowing for the possibility that the Golden Mile dolerite was a high-level intrusion at the Upper Basalt / Black Flag Group interface. The stratigraphy of post Upper Basalt rocks, including three newly defined formations, is separated on the basis of this work into four units from oldest to youngest: 'Talbot formation'; White Flag Formation; 'Gibson-Honman formation' (~2675 Ma); and 'Gidji Lake formation' (~2660 Ma). Gibson-Honman formation includes felsic volcanic rocks at Gibson-Honman Rock, Lakewood dacitic volcanics, and Perkolilli rhyolitic volcanics. Gidji Lake formation includes felsic volcaniclastic rocks at Gidji, Binduli Porphyry Conglomerate and Grave Dam Grit at Kanowna. The stratigraphy includes unconformities between White Flag Formation and Talbot formation (locally), and between Gibson-Honman and Gidji Lake formations. The Panglo member in the Kanowna district is interpreted as a correlative of the Kurrawang Formation, and represents a major change to the district stratigraphy that identifies late, unconformable clastic sequences in the vicinity of the Kanowna Belle gold deposit. Five major deformation events are separated into pre-Kurrawang and post-Kurrawang deformation episodes, which record a change from early extension to bulk contraction, with the latter including syn-orogenic clastic sedimentation. Major map scale F1 folds are located at Kanowna and the Golden Mile in a restricted distribution that may reflect typically poor preservation of D1 fabrics. Localised syn-orogenic extension resulted in the deposition of linear fault-controlled, late clastic sedimentary sequences at <2650 Ma (Kurrawang, Panglo), unconformably overlying F2 folded rocks. The deposition of those sequences marks the onset of penetrative deformation over a relatively short time interval (~2650 – 2639 Ma). A regionally pervasive S3 foliation transects F1 and F2 fold axial planes. The S3 foliation trends uniformly over the district, and is axial planar to F3 folds with inclined axial planes in the late clastic sequences. The maximum age of the regional S3 foliation is constrained by the <2650 Ma rocks that are folded and foliated by it, and a minimum age at 2639±3 Ma from Lode-Au veins that were synchronous with and overprinting the regional foliation. The Zuleika Shear Zone marks a domain boundary that juxtaposes crustal blocks with minor stratigraphic differences and thickness of sequences, yet the blocks do not have significantly different deformation intensity or metamorphic grade. Fault bounded domains in the Kalgoorlie Terrane were therefore not diverse crustal blocks amalgamated by strike slip or accretion, but were more likely subjacent depocentres, possibly half-grabens, bounded by early extensional faults such as the Zuleika Shear Zone and Bardoc Tectonic Zone. Geological sequences of the Yindarlgooda Dome show no major differences in lithotectonic assemblages, stratigraphic sequence, or age, from sequences in the adjacent Boorara Domain. On this basis, the allocation of 'terrane boundary' status to the Mount Monger Fault as separating a western back-arc (Kalgoorlie Terrane) from an eastern accreted volcanic arc (Gindalbie Terrane) is suspect, and casts doubt on the application of subduction / arc-accretion models to greenstones of the southern EGP. Models that propose rifting of a pre- ~2700 Ma greenstone basement may be better analogues for the tectonic setting of the Kalgoorlie greenstones. At a regional scale, major gold districts in the EGP have spatial and temporal relationships with unconformable, late clastic sedimentary sequences that mark areas of thick greenstone preservation. There is diversity of mineralisation styles and settings in the largest gold deposits, including early syn-volcanic hydrothermal alteration and mineralisation systems, and late-tectonic, vein hosted lode-Au deposits. High-level mineralisation styles were developed early in the formation of the greenstone belts with spatially coincident, late-tectonic mineralisation, indicating persistent mineral systems at fixed locations throughout several uplift and deformation cycles. That persistence suggests fundamental structural controls. Structural controls on the different mineralisation styles include early-formed disseminated sulphide replacement mineralisation (e.g. Binduli) deformed and cut by late, syn-tectonic lode-Au vein style mineralisation (e.g. Binduli; Kundana). The Binduli district is spatially associated with the ~2664 Ma Binduli Porphyry Conglomerate unconformity that is interpreted to separate the Gibson-Honman and Gidji Lake formations. Kanowna Belle gold deposit is hosted in hypabyssal porphyritic rocks that have a spatial association with a ~2660 Ma unconformity at the base of the Grave Dam sequence (Gidji Lake formation). Unconformable sedimentary and volcaniclastic rocks of the Gidji Lake formation (~2660 Ma) are present in the vicinity of the eastern margin of the world class Mount Charlotte / Fimiston gold camp. This spatial association of major gold deposits with rocks located above an unconformity internal to the Black Flag Formation is a new understanding of the critical controls on Neoarchaean gold deposits and is a key criterion for area selection in exploration.

Banded iron formations (BIF) are predominantly Precambrian sedimentary rocks composed of alternating layers of iron-rich minerals (commonly hematite and magnetite, but also siderite, chlorite, and grunerite) and silica-rich minerals (e.g., quartz or chert) in which the Fe content of the entire rock is at least 15 wt. %. Although typically thought of as strictly Fe resources, such as in the worldclass Archean-Proterozoic Pilbara Craton of NW Australia, some BIF are associated with non-Fe ore resources, including (but not limited to) gold deposits in greenstone terranes. Due to fluctuations in ocean and atmospheric chemistry, BIF are commonly interbedded with pyritic black shales, which are regarded as waste material in Fe deposits but nonetheless are of great scientific interest (as are BIF) and potentially play a role in the creation of some gold resources (recent research has suggested that black shales are a source of Au and As in sediment-hosted gold deposits). The source of gold in these BIF, or more accurately, in BIF that host gold deposits, is a contentious issue in historical and modern economic geology. Over the past 40 years, debate in the economic geology community has revolved around whether the gold now in such deposits was an original part of the iron formation, or if it was introduced from an external, distant source. Less attention has been paid to the sources of As, Ag, and Te in these deposits, but as they commonly co-exist with gold in ore zones, determining their provenance is of relevance in assessing the origin of sediment-hosted and greenstone-hosted gold deposits. In this thesis, black shales are investigated as the source of gold, arsenic, and tellurium at two BIF-hosted gold districts, Randalls (Australia) and Homestake (USA). The primary tools used in this investigation were petrography, textural analysis, whole-rock XRF, optical and scanning electron microscopy, and laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS). In particular, sulfides associated with the BIF-gold ores (e.g., pyrite, pyrrhotite, and arsenopyrite) and ‘background’ sulfides in non-BIF rocks a short distance from the ore zones were analyzed using laser ablation imaging and spot methods to determine their trace element contents and zonation (especially their Au, As, Ag, and Te concentrations). Special attention was paid to fine-grained, carbonaceous and sulfidic (meta) sedimentary rocks, or black shales, as these are widely acknowledged to be excellent source material for sediment-hosted gold, nickel, and copper deposits. The Archean Randalls district (including Lucky Bay) is located in the southern Eastern Goldfields Superterrane, one of several crustal fragments that make up the Archean-Proterozoic Yilgarn Craton. The Yilgarn is one of the most gold-rich areas in the world, containing an estimated 9500 t (270 million ounces [Moz]) of Au. The Randalls district is located in the Belches Basin, one of several so-called ‘Late-Stage Basins’ in the Eastern Goldfields, and contains three BIF-hosted gold deposits (Cock-Eyed Bob, Maxwells, and Santa-Craze). Other styles of gold mineralization do occur in the area, such as the Daisy Milano deposit (quartz-vein lodes in altered basalts) and the Imperial-Majestic deposits (possible intrusion-related gold systems). The >40 Moz (1300 t Au) Paleoproterozoic Homestake BIF-hosted deposit (the largest of its kind in the world) is located in the Black Hills dome of western South Dakota, which consists of an Archean- Proterozoic metasedimentary/metaigneous core flanked by Phanerozoic sediments; the current geologic architecture of the Black Hills was created during the 80–40 Ma Laramide orogeny, which formed the Rocky Mountains. Numerous felsic and alkalic intrusions were emplaced in all Precambrian and Phanerozoic units during this time, some of which are present in the Homestake mine area. These are commonly pyrite-bearing. At Randalls, the ore host BIF is enveloped by km-thick quartz- and feldspar-rich turbidites, with very little shale (and virtually no carbonaceous black shale). However, 10 km west of Cock-Eyed Bob is the Lucky Bay prospect, which contains abundant carbonaceous, fine-grained, and sulfidic (meta) black shale. This unit contains several types of pyrite, including pyrite nodules that are orders-of-magnitude more enriched in Au (0.1–2 ppm), As (500–10,000 ppm), Ag (1–100 ppm), and Te (0.5–50 ppm) than average crustal background levels. Other elements enriched in the Lucky Bay nodules are Co (500–1000 ppm), Ni (500–1000 ppm), Cu (100–500 ppm), Zn (50 ppm), Se (10–50 ppm), Mo (1–5 ppm), Sb (100–200 ppm), Hg (1000–2000 counts per second), Tl (0.5–10 ppm), Pb (500–1000 ppm), and Bi (20-50 ppm). Structural relationships observed in drill core and under the microscope suggest that these nodules are pre-metamorphic and pre-deformation, as evidenced by the ‘wrapping’ of bedding around the nodules. Pressure shadows containing quartz, mica, and a second generation of pyrite (plus sphalerite and chalcopyrite) also point to pre-deformational (likely syn-sedimentary or early diagenetic) growth. Likewise, fine-grained (<0.5 mm diameter) anhedral pyrite and larger (up to 5 mm), partially recrystallized pyrite nodules in etamorphosed black shale at Homestake also have high amounts of Au (up to 0.5 ppm, average 0.3 ppm), As (up to 10,000 ppm), Ag (~10 ppm), Te (~10 ppm), and the other ore-associated elements noted above for pyrite nodules at Lucky Bay, though not quite at the same level as those nodules. This is likely due to the greater intensity of metamorphism (lower-middle amphibolite facies) experienced by lithologies at the Homestake deposit and surrounds, which recrystallized and partially converted the pyrite to pyrrhotite; pyrite at Lucky Bay (lower-middle greenschist facies) was spared this same fate. Furthermore, whole-rock analyses of the pyrite-bearing lithologies at Homestake show that the unit contains levels of V, Ag, Mo, Cu, and Zn on par with anomalous carbonaceous black shale (as published in the literature). Lead isotopes of the pyrite nodules and the diagenetic pyrites from both localities appear to reinforce the claim that these pyrites did indeed form early in the history of the sedimentary units that host them. However, whereas Pb-Pb model ages of the Lucky Bay nodules are within error of the U-Pb depositional age, those from Homestake are hundreds of millions of years younger than the established intrusive, crystallization and depositional ages for all Proterozoic rock types in the Black Hills, suggesting that Pb loss and isotopic resetting had a major effect on minerals and rocks in and around Homestake. Futhermore, Pb isotope systematics of the eastern Yilgarn Craton are complex, such that two pyrites of otherwise different generations (i.e., sedimentary vs. ore-stage pyrite) can have Pb isotope compositions within error of each other. These aspects of the pyrite Pb isotope data from Lucky Bay and Homestake are here presented as caveats, not insurmountable obstacles, to the study and understanding of Pb isotope systematics in sulfides. The sulfides within ore zones at both deposits do not contain the same high levels of trace elements, nor (with rare exceptions) do the amounts of the trace elements they have rival the levels of concentration seen in the various sedimentary pyrites outside the ore zone. At Randalls, pyrrhotite and arsenopyrite (the two major ore sulfides) are enriched in Co (up to 2000 ppm), Ni (up to 250 ppm), Se (up to 60 ppm), Mo (up to 50 ppm), Ag (up to 15 ppm), Sb (up to 200 ppm), and Te (up to 500 ppm). Certain elements, such as Mo and Te, are enriched only in arsenopyrite, while the rest are enriched at similar levels in both sulfides (furthermore, Te and Mo are more highly enriched in ore-stage arsenopyrite at Randalls than any other sulfide studied in this work). Arsenopyrite and pyrrhotite from Homestake (again the dominant ore zone sulfides) contain Co (50–1000 ppm), Ni (50–500 ppm), Se (100–200 ppm), Mo (10–100 ppm), Sb (50–500 ppm), Pb (1–100 ppm), and Bi (0.1–100 ppm). Many of the trace elements in the Randalls sulfides are strongly zoned, whereas the Homestake sulfide trace elements are more (but not completely) homogenized; as with the sedimentary pyrite above, this is interpreted to reflect higher metamorphic conditions attained at Homestake (lower-middle amphibolite facies) compared to Randalls (upper greenschist facies), which would lead to the expulsion of most trace impurities, or at least the erasure of original zonation. This work demonstrates that certain trace elements, including those most commonly associated with sediment-hosted and greenstone-hosted gold deposits, were concentrated in upper-crustal siliciclastics during sedimentation or early diagenesis (that is, prior to later events that gave rise to sediment-hosted and greenstone-hosted gold deposits), and particularly in syn-sedimentary to early diagenetic pyrite. This research also has the potential to address metal source issues in some very large orogenic gold resources around the world: for example, an extension of the work completed here was conducted at the world-class, ~60 Moz dolerite-hosted Golden Mile Au district in Kalgoorlie, ~60 km NW of Lucky Bay and Randalls. Despite the overwhelming abundance of basalt, komatiite, and dolerite, three separate black shale layers are present in the district as interflow sediments between the mafic/ultramafic volcanic flows. All three units (Kapai Slate, Oroya Shale, and Black Flag Group shale) contain pyrite nodules with very similar internal and external textures to those at Lucky Bay. The likenesses between these nodules’ textures and the Lucky Bay nodules’ (including deformed bedding around the nodules) indicate that those at the Golden Mile are diagenetic, not hydrothermal. LA-ICP-MS geochemical studies of the Golden Mile pyrite nodules reveals differences between the nodules from each formation, but also consistent characteristics. One of these, the Oroya Shale, contains diagenetic pyrite nodules with very similar textures to those from Lucky Bay, but the amount of Au and other trace elements contained in these nodules is significantly higher (e.g., up to 10 ppm Au dissolved in the pyrite structure). Given the abundance of this trace element-enriched pyrite in black shales (~5–10 vol. %), and the thickness and extent of this rock type at Lucky Bay (~7 km3), Homestake (~12 km3), and the Golden Mile (~3 km3), it is at least conceivable that a portion of the gold ore (plus As, Ag, and Te, in their various forms) now in the banded iron formations (and, by extension, the Golden Mile Dolerite) was sourced from the black shale units within the same succession (i.e., the stratigraphic footwall or hangingwall to the ore host).