Jour 15/30 du Challenge 📘 Fiche Exercice N°15 : Simulation gaussienne conditionnelle – De la génération de champs aléatoires à la représentation de l’incertitude spatiale ✍️ Ing. NGUEYAP AMBANI AUGUSTIN SERGE (Ingénieur Géologue – Spécialiste) Cette fiche présente : 1. Objectif de l’exercice 2. Rappel mathématique fondamental 3. Mise en contexte géoscientifique 4. Données fournies 5. Questions 6. Corrigé détaillé et commenté 7. Transition vers la géostatistique 8. Application pratique (R / Python) 9. Synthèse 10. Remerciements et perspectives 🙏 Merci à toutes celles et ceux qui aiment 👍, commentent 💬 et partagent 🔄 ce contenu. Votre soutien nous permet de continuer à proposer des formations de qualité. 🤝 Nous restons disponibles pour échanger et collaborer avec toute personne intéressée par ces thématiques.

The top 30 miners are projected to spend $121.6 billion in 2026, a decade high. After the supercycle bust of 2013–14, the sector spent a decade deleveraging. Free cash flow went to balance sheets, not projects. Now capital is moving again, but the character of that spending tells a different story to the headline number. Copper dominates the agenda with BHP, Rio Tinto, Glencore and Freeport-McMoRan all flag it as the priority. But look at where the money is actually going. Brownfield expansions. Debottlenecking. Sustaining capex at mature operations. Resolution, El Pachón, Sakatti are either deferred or still years from first production. Anglo American is cutting capex to the bone ahead of a potential Teck Resources Limited merger. Vale trimmed its 2025 budget by $1 billion. The industry is spending more, but it's spending defensively. Cash-generative incumbents are being sweated harder. New supply isn't being built, it's being studied, postponed, or quietly shelved. This matters because the demand projections driving these investment decisions assume copper, nickel and critical minerals will be needed at scale within the decade. The supply response required to meet that demand isn't in the pipeline at the pace or volume needed. Capex is rising, but the structural gap between what's being built and what will be needed keeps widening. After 2027, spending is forecast to fall again as major projects wind down. The industry will face the same growth dilemma it's been circling for years just with less time to solve it. Rational decisions at the company level. A collective failure at the industry level. For more of my takes on the resource industry sign up to my weekly newsletter www.kamoacap.com Source: S&P Global Market Intelligence, March 2026

In open-pit mining, productivity depends heavily on how efficiently material moves from the pit to the processing plant or waste dumps. At the centre of this movement are haul roads — the pathways that carry thousands of tonnes of material every day. This week, we examine the significance of haul road design and its crucial role in ensuring safety, minimising costs, and enhancing operational efficiency. 🚜 What Are Haul Roads? Haul roads are specially designed roads used by heavy mining trucks to transport ore and waste within a mine. These roads must withstand extremely heavy loads while allowing safe and efficient truck movement. Unlike public roads, haul roads are engineered specifically for large mining equipment and continuous operations. 📏 Key Elements of Haul Road Design 1. Road Width Must accommodate large haul trucks safely, especially on two-way traffic routes. 2. Gradient (Slope) Steeper roads increase fuel consumption, reduce truck speed, and increase wear. 3. Road Surface Quality Proper grading and maintenance reduce tyre damage and improve vehicle stability. 4. Safety Berms Raised edges along the road prevent trucks from accidentally leaving the roadway. ⚙️ Why Haul Roads Matter 🚀 Improves truck productivity and cycle times 💰 Reduces fuel consumption and operating costs 🛠️ Minimises equipment wear and tyre damage 🛡️ Enhances safety for operators and equipment 📉 Reduces downtime due to poor road conditions Well-maintained haul roads can significantly improve overall mine performance. 🎯 The Bigger Picture Haul road design may seem simple, but it directly influences: Truck efficiency Production targets Operating costs Safety performance In many mines, small improvements in haul road quality lead to major gains in productivity. 💬 In your experience or opinion, what affects haul road performance the most — gradient, surface condition, or traffic management? If this added value, like, comment, follow, and repost to keep advancing mining knowledge.

¿Sabías que la sincronización entre taladros determina no solo la fragmentación, sino también la geometría de la pila, las vibraciones y la seguridad de tu operación? Dominar el arte del tiempo en voladura es lo que separa una voladura eficiente de una fuera de control. 🧠 Claves técnicas que debes conocer: ⚡ La Ventana de los 8 Milisegundos Si dos taladros inician con menos de 8 ms de diferencia, actúan como una sola carga. Esto puede amplificar vibraciones y generar sobre rotura. 📏 Alivio de Tiempo (ms/m) Se mide en milisegundos por metro de burden. El intervalo correcto define si la pila será compacta (ideal para palas) o extendida (para cargador frontal o cast blast). 📊 Guía rápida de intervalos: 🔹

Most mineral asset valuations are signed off by practitioners with dangerous gaps in at least one of three critical disciplines: 👉 Resource estimation science 👉 Commodity economics 👉 Financial management The codes permit it. The markets absorb the consequences. It’s time more is demanded from the profession. 🫵 Rigorous, integrated understanding is not optional — it is the baseline of competence. Defensible mineral resource estimation and valuation requires mastery across three distinct but inseparable disciplines: 👉 Geostatistical estimation and its inherent limitations 👉 The distinction between geological confidence, grade continuity, and grade uncertainty 👉 The economics and financial management that underpin mineral asset valuation 🫵 This is not just a technical problem — it is a systemic weakness in the global framework for mineral asset governance. How confidence limits are established, why estimated grade parameters differ from global sample statistics, why classical statistics form the inviolable ceiling of estimation certainty, and why the dangerous conflation of geological confidence with grade estimation uncertainty persists — all of it points to the same conclusion: The separation of mineral resource reporting codes from valuation codes, combined with the absence of formal economic and financial competency requirements, is a risk the profession can no longer afford to ignore. 📄 Full essay below.

As perfuratrizes são equipamentos utilizados para realizar furos em rochas, com o objetivo principal de permitir o desmonte com explosivos, investigação geológica ou instalação de suportes. São fundamentais tanto na mineração a céu aberto quanto na subterrânea. Principais Funções 1 Perfuração para Desmonte Realizam furos no maciço rochoso. Esses furos são carregados com explosivos. Após a detonação, a rocha fragmentada é carregada por escavadeiras. 2 Perfuração para Pesquisa Geológica Coleta de testemunhos (sondagens). Determinação de teor, estrutura e profundidade do minério. 3-Perfuração para Estabilização Instalação de tirantes e chumbadores. Controle geotécnico em taludes e galerias. Tipos de Perfuratrizes na Mineração Perfuratrizes Rotativas Usadas principalmente em minas a céu aberto. Indicadas para furos de grande diâmetro. Muito comuns em minas de ferro. Perfuratrizes DTH (Down-The-Hole) Martelo funciona no fundo do furo. Alta eficiência em rochas duras. Produzem furos mais retos e precisos. Perfuratrizes Top Hammer Martelo hidráulico fica na parte superior. Ideais para furos menores e médios. Jumbo de Perfuração (Subterrânea) Equipamento montado sobre chassis. Muito usado em túneis e minas subterrâneas. Vantagens Alta precisão na perfuração Maior produtividade Redução de custos com explosivos Melhor fragmentação da rocha Segurança operacional. Importância no Ciclo Mineiro A perfuração é a primeira etapa do desmonte de rochas. Se for mal executada, pode causar: - Má fragmentação - Aumento do custo de britagem - Perda de produtividade - Riscos de segurança.

Comparto estudio “The Effect of Stress Damage on Dilution in Narrow Vein Mines” el cual analiza cómo los altos esfuerzos en el macizo rocoso pueden generar mayor dilución en minería subterránea de vetas angostas. El efecto del daño por esfuerzos en la dilución se ha vuelto cada vez más relevante a medida que aumenta la profundidad de la minería. En el caso de la minería de vetas angostas, la extracción progresiva de long-hole rings puede generar una zona de altos esfuerzos que se desplaza hacia el brow del caserón. Esto provoca que el hanging wall (pared colgante) y el footwall (pared yacente) experimenten un aumento significativo en la relación esfuerzo–resistencia cuando el brow avanza. En algunos casos, esta relación puede ser lo suficientemente alta como para producir fracturamiento o daño en el macizo rocoso. El objetivo del estudio descrito en este trabajo fue investigar si el daño por esfuerzos produce un aumento significativo de la dilución. Para ello, se analizó la sobre–excavación (overbreak) en 410 casos de estudio de la mina de oro Kundana en Australia Occidental. El personal de la mina ya había realizado estudios de calibración de los niveles de esfuerzo que generan daño en el macizo rocoso. Esta calibración, junto con modelamiento numérico, mostró que las paredes de caserones afectadas por daño por esfuerzos presentaban en promedio 50% más sobre–excavación que aquellas donde los esfuerzos no superaban el criterio de daño. Para un ancho de minado de diseño de 1,5 metros, y considerando que ambas paredes del caserón están afectadas, esto representa un aumento del 36% en la dilución. Sin embargo, después de ajustar los resultados para posibles fuentes de sesgo, la diferencia se redujo a un promedio de 0,10 metros por pared del caserón, lo que representa aproximadamente 13% de dilución para el ancho de minado considerado. Por lo tanto, el potencial de sobre–excavación asociado al daño por esfuerzos debería ser considerado como parte de cualquier evaluación de dilución en minería de vetas angostas.

Surface Mining: Haul Truck Productivity ‘Ready Reckoners’ are useful for a ‘quick stab’ throughput estimate. Always.