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Development and application of feature engineered geological layers for ranking magmatic,volcanogenic,and orogenic system components in Archean greenstone belts

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Geoscience Frontiers 2024年第2期15卷 251-273页

作者： R.M.Montsion S.Perrouty M.D.Lindsay M.W.Jessell R.Sherlock Mineral Exploration Research Centre Harquail School of Earth SciencesGoodman School of MinesLaurentian UniversitySudburyOntario P3E 2C6Canada Centre for Exploration Targeting School of Earth SciencesThe University of Western Australia35 Stirling HighwayCrawley 6009Australia Commonwealth Scientific and Industrial Research Organization Mineral Resources26 Dick Perry AveKensingtonWA 6151Australia ARC Centre for Data Analytics for Resources and Environments(DARE) Perth and SydneyAustralia

Geologically representative feature engineering is a crucial component in geoscientific applications of machine learning.Many commonly applied feature engineering techniques used to produce input variables for machine learning apply geological knowledge to generic data science techniques,which can lead to ambiguity,geological oversimplification,and/or compounding subjective bias.Workflows that utilize minimally processed input variables attempt to overcome these issues,but often lead to convoluted and uninterpretable results.To address these challenges,new and enhanced feature engineering methods were developed by combining geological knowledge,understanding of data limitations,and a variety of data science techniques.These include non-Euclidean fluid pre-deformation path distance,rheological and chemical contrast,geologically constrained interpolation of characteristic host rock geochemistry,interpolation of mobile element gain/loss,assemblages,magnetic intensity,structural complexity,host rock physical properties.These methods were applied to compiled open-source and new field observations from Archean greenstone terranes in the Abitibi and western Wabigoon sub-provinces of the Superior Province near Timmins and Dryden,Ontario,respectively.Resulting feature maps represent conceptually significant components in magmatic,volcanogenic,and orogenic mineral systems.A comparison of ranked feature importance from random forests to conceptual mineral system models show that the feature maps adequately represent system components,with a few exceptions attributed to biased training data or limited constraint data.The study also highlights the shared importance of several highly ranked features for the three mineral systems,indicating that spatially related mineral systems exploit the same features when available.Comparing feature importance when classifying orogenic Au mineralization in Timmins and Dryden provides insights into the possible cause of contrasting endowment being related to fluid source.The study demonstrat

关键词： Machine learning Random forests Mineral systems Magmatic Ni-Cu-PGE Volcanogenic Massive Sulfide(VMS)Cu-Zn-Pb-Ag(-Au) Orogenic Au Abitibi Wabigoon

Rock support in strainburst-prone ground

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International Journal of Mining Science and Technology 2019年第4期29卷 529-534页

作者： M.Cai MIRARCO Laurentian University Bharti School of Engineering Laurentian University Key Laboratory of Ministry of Education for Safe Mining of Deep Metal Mines Northeastern University

Strainburst is the most frequently encountered type of rockburst in underground mines.Strainburst occurs when the stress near the excavation boundary reaches the peak strength of the rock mass causing it to fail suddenly and violently.To mitigate strainburst damage risk,effective rock support is needed.In strainburst-prone grounds,it is critical to have rock support components to fulfill the role of rock reinforcement first to prevent rock failure.On the other hand,well-retained and reinforced rock masses may be excessively deformed and fail violently.In such a case,yielding elements are needed in the rock support system to absorb the excess strain energy released due to rock failure.The conventional method to support strainburst-prone grounds is to install rock reinforcement system using rebar and mesh first and then install yielding support system using dynamic rockbolts at a later stage.This two-stage rock support installation process is not effective because it can adversely impact mine production schedule.This paper presents a new,patented dynamic rockbolt,which is called superbolt and is developed for rock support in burst-prone grounds.Laboratory testing confirmed that the superbolt has superb capacity to achieve the goal of reinforcing and holding rock masses.The superbolt is characterized by high dynamic energy absorption capacity,consistent performance,and the ability to withstand repeated dynamic loading.The new rockbolt can be used in a one-pass rock support system to facilitate rapid drift development in underground mines and increase mine safety and productivity.

关键词： Rockburst Strainburst Rock support Dynamic failure Energy Capacity

A conceptual framework for characterizing mineralized waste rocks as future resource

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International Journal of Mining Science and Technology 2019年第3期29卷 429-435页

作者： Bright Oppong Afum Dylan Caverson Eugene Ben-Awuah Mining Optimization Laboratory Bharti School of Engineering Laurentian University

Conventional mining practices do not extract all mineralized rocks due to prevailing economics.Improvement in mineral prices and processing recovery(technology)could potentially make mineralized waste rocks profitable.A well-integrated mining strategy that focuses on both economic and physical resource depletion is vital to the management of non-renewable mineral resources.In this paper,a conceptual framework that maximizes the benefits of mining and processing mineralized waste rocks as future resource is proposed.Governmental policy and technical reforms that ensure mining companies incorporate the proposed mineralized waste rocks management framework in their long-term strategic mine plans have been recommended.

关键词： Resource depletion Mineralized waste Conventional mining practices Policy reform Technical reform Future resource

Hydrogen Sulfide Promotes Adipocyte Differentiation, Hyperplasia, and Hypertrophy

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Engineering 2023年第1期20卷 36-48页

作者： Richa Verma Ming Fu Guangdong Yang Lingyun Wu Rui Wang Cardiovascular and Metabolic Research Unit Laurentian UniversitySudburyON P3E 2C6Canada Department of Biology York UniversityTorontoON M3J 1P3Canada

Hydrogen sulfide (H2S) is endogenously produced in adipocytes and fat tissues and stimulates adipogenesis. The integrated pathogenic effects of H2S on the development of obesity and the underlying mechanisms, however, have been unclear. Here, we find that a decreased endogenous H2S level lowered lipid accumulation in mouse adipocytes. Exogenous H2S treatment significantly increased the adipogenesis of primary mouse preadipocytes after six days of adipogenic induction. In the early phase of adipogenesis, H2S increased cell proliferation and prepared cells to go through hyperplasia. After H2S treatment for ten days, preadipocytes exhibited significantly greater cell surface area and diameter, indicating cell hypertrophy. Although it stimulated lipid accumulation and adipogenesis, H2S had no effect on lipolysis. With nutrition overload and high glucose/insulin incubation, H2S further stimulated glucose consumption and deteriorated adipocyte hypertrophy. H2S upregulated hyperplasia genes (CCAAT/enhancer-binding protein (C/EBPβ), cell division cycle 25 (Cdc25), minichromosome maintenance 3 (Mcm3), and cell division cycle 45 (Cdc45)) and cyclin-dependent kinase 2 protein (Cdk2), which regulates cell proliferation. H2S also upregulated the insulin receptor β (Irβ)-activated mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) pathways, leading to adipogenesis. In conclusion, H2S increases adipocyte differentiation, hypertrophy, and hyperplasia, implying that it plays a pathogenic role in obesity disorder.

关键词： Adipogenesis Adipocytes Gasotransmitter Glucose H2S Insulin Lipid Obesity

Diversity of hydrogen sulfide concentration in plant:a little spark to start a prairie fire

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Science Bulletin 2018年第20期63卷 1314-1316页

作者： Zhuping Jin Zhiqing Wang Guangdong Yang Yanxi Pei School of Life Science Shanxi University Department of Chemistry and Biochemistry Laurentian University

The ubiquitous and versatile signal-transduction role of hydrogen sulfide (H2S)has been revealed in mammals and plants in recent years [1-5].It is very important to grasp the physiological concentrations of H2S in vivo because of its toxic characteristics at high concentrations.However,the reported data fail to reach an agreement owing to the use of different methods and technique limitations. In fact,this is a common problem for gasotransmitters.What is the exact boundary between the physiological and toxicological concentration?What is the accurate endogenous content?These problems have been plaguing us even though there are a great number of research papers that explore H2S signals.

关键词： hydrogen sulfide

Rates and processes affecting As speciation and mobility in lake sediments during aging

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Journal of Environmental Sciences 2018年第4期30卷 338-347页

作者： Alan Lock Dirk Wallschlager Nelson Belzile Graeme Spiers Celine Gueguen Environmental and Life Sciences Graduate Program Trent University School of the Environment Department of Chemistry and Water Quality CentreTrent University Department of Chemistry Laurentian University School of the Environment Departments of Earth Sciences and BiologyLaurentian University School of the Environment and Chemistry Department Trent University

Sediments from an arsenic（As） contaminated groundwater vent site were used to investigate As（ Ⅲ） binding, transformation and redistribution in native and iron oxide amended lake sediments using aging spiked batch reactions and a sequential extraction procedure that maintains As（V） and As（ Ⅲ） speciation. In the native sediments, fractionation analysis revealed that 10% of the spiked As（ Ⅲ） remained intact after a 32-day aging experiment and was predominantly adsorbed to the strongly sorbed（NH4H2PO4 extractable） and amorphous Fe oxide bound（H3PO4 extractable） fractions. Kinetic modelling of the experimental results allowed identifying the dominant reaction path for depletion of dissolved As（ Ⅲ） to As（ Ⅲ）absorbed on to the solid phase, followed by oxidation in the solid phase. Arsenite was initially adsorbed primarily to the easily exchangeable fraction（（NH4）2SO4 extractable）, then rapidly transformed into As（V） and redistributed to the strongly sorbed and amorphous Fe oxide bound fractions. Oxidation of As（ Ⅲ） in recalcitrant fractions was less efficient. The iron oxide amendments illustrated the controls that iron oxides can have on As（ Ⅲ） binding and transformation rates. In goethite amended samples As（ Ⅲ） oxidation was faster and primarily occurred in the strongly sorbed and amorphous Fe oxide bound fractions. In these samples,19.3 μg Mn was redistributed（compared to the native sediment） from the easily exchangeable and crystalline Fe oxide bound fractions to the strongly sorbed and amorphous Fe oxide bound fractions, indicating that goethite may act as a catalyst for Mn（Ⅱ） oxidation, thereby producing sorbed Mn（ Ⅲ/Ⅳ ）, which then appears to be involved in rapidly oxidizing As（ Ⅲ）.

关键词： Arsenite Oxidation Fractionation Redistribution Modelling

An Early Cretaceous gold mineralization event in the Triassic West Qinling orogen revealed from U-Pb titanite dating of the Ma'anqiao gold deposit

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Science China Earth Sciences 2023年第2期66卷 316-333页

作者： Chongguo HE Jianwei LI Daniel J.KONTAK Xiaoye JIN Yafei WU Hao HU Bo ZU Xueling YU Shaorui ZHAO Shiguang DU Yunlong ZHU Huan TAO State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan430074China School of Earth Resources China University of GeosciencesWuhan430074China Harquail School of Earth Sciences Laurentian UniversitySudburyOntarioP3E 2C6Canada

The West Qinling orogen in central China,formed from continental collision between the North China and Yangtze cratons in the Late Triassic,hosts numerous gold deposits with a total Au endowment of about 2000 t.Most deposits were emplaced at ca.250-195 Ma and are genetically associated with the Triassic orogenesis.Here in situ U-Pb titanite dating with laser ablation inductively coupled plasma mass spectrometry indicates the Ma’anqiao gold deposit in the northern portion of this orogen has a distinctive age and under a contrasting tectonic regime.This structurally controlled gold deposit is hosted in Late Ordovician to Early Silurian sub-greenschist facies metasedimentary rocks.The gold mineralization is hosted in quartz-pyritepyrrhotite veins and pyrite-pyrrhotite disseminations in hydrothermally altered rocks,which are crosscut by K-feldspar-calcitechlorite±pyrite veins.Titanite,present both in the disseminated sulfide ores and later veins,was used for in situ U-Pb dating.Titanite from three disseminated sulfide ore samples with Th and U averaging 27.46 and 39.31 ppm(1 ppm=1μg g^(-1)),respectively,yielded lower-intercept ages of 121.1±3.1 to 120.7±3.5 Ma(2σ)in the Tera-Wasserburg diagram.Titanite from three later vein samples with much lower Th and U concentrations averaging 2.74 and 16.21 ppm,respectively,yielded overlapping ages of 120.8±3.2 to 120.3±5.8 Ma(2σ).These new titanite U-Pb ages tightly constrain the formation of the Ma’anqiao gold deposit at ca.121-120 Ma and,when combined with independent geological data,indicate it is not related to the Triassic Qinling orogeny.Rather,its formation is attributed to lithospheric thinning and destruction of the North China craton during the Late Jurassic to Early Cretaceous which has generated numerous gold deposits along the southern margin of this craton.This catastrophic event caused extensive magmatism in large areas of the North Qinling terrane and northern edge of the West Qinling orogen immediately to the south of the North China craton.The heat flux and el

关键词： Titanite U-Pb dating Early Cretaceous Orogenic gold deposit Ma’anqiao West Qinling orogen

Wavelet Denoising Applied to Hardware Redundant Systems for Rolling Element Bearing Fault Detection

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Journal of Dynamics, Monitoring and Diagnostics 2023年第2期2卷 133-143页

作者： Dustin Helm Markus Timusk Bharti School of Engineering laurentian university SudburyOntarioCanada

This work presents a novel wavelet-based denoising technique for improving the signal-to-noise ratio(SNR)of nonsteady vibration signals in hardware redundant systems.The proposed method utilizes the relationship between redundant hardware components to effectively separate fault-related components from the vibration signature,thus enhancing fault detection accuracy.The study evaluates the proposed technique on two mechanically identical subsystems that are simultaneously controlled under the same speed and load inputs,with and without the proposed denoising step.The results demonstrate an increase in detection accuracy when incorporating the proposed denoising method into a fault detection system designed for hardware redundant machinery.This work is original in its application of a new method for improving performance when using residual analysis for fault detection in hardware redundant machinery configurations.Moreover,the proposed methodology is applicable to nonstationary equipment that experiences changes in both speed and load.

关键词： fault detection hardware redundancy vibration wavelet denoising

A Single Hypoxic Event Ameliorates Pilocarpine Induced Hyperkinetic Movements in Planaria

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Natural Science 2022年第4期14卷 149-156页

作者： Teagan Neufeld Trevor N. Carniello Blake T. Dotta Behavioural Neuroscience School of Natural Sciences Laurentian University Sudbury ON Canada

Intermittent hypoxia or hypoxia therapy is exposing an individual to oxygenation conditions that are below atmospheric levels in a planned or acute timeframe. Hypoxia therapy is a potentially novel therapeutic strategy for a variety of pathologies including: mitochondrial disorders, exercise training, and mild cognitive impairments. Mitochondrial dysfunction, hyperkinetic movements, and cognitive impairments are hallmarks of seizures and status epilepticus (SE). A seizure can be considered uncontrolled electrical activity in the brain and SE is a seizure lasting more than 30 minutes, or multiple seizures without regaining consciousness in between. We examined the possibility of using the Pilocarpine model for seizure like activity on brown planaria (Dugesia tigrine). Pilocarpine is a muscarinic acetylcholine receptor agonist capable of creating seizure related brain damage. We utilized 5 mM dosages of pilocarpine and then measured open field behaviour for 3 minutes. Mobility and aversive hyperkinetic movements were observed throughout the measurement phase. After exposure to 5 mM pilocarpine, the planaria displayed behaviours consistent with seizures (e.g. aversive hyperkinetic movements and decreased mobility). Additionally, we measured the effects of an acute hypoxic event on Planaria behaviour. We used 25% carbonated water to create a hypoxic environment for the planaria and then measured mobility and hyperkinetic movements for 3 minutes. We noted that exposure to the hypoxic en-vironment produced no changes in behaviour. However, the aversive hyperkinetic move-ments produced with pilocarpine administration were completely absent when a brief (3 minutes) hypoxic episode followed the pilocarpine exposure (p < 0.05). Aversive behav-iours remained present when the ordering of pilocarpine and hypoxia were counterbal-anced. This ordering effect was consistent across 40 trials. Further evaluation of the pilo-carpine seizure model and intermittent hypoxia on planarian behaviour is warranted.

关键词： Hypoxia Pilocarpine Planaria Hyperkinetic Movements Seizure Model