You're a petroleum engineer confronting that dreadful question, “Where to drill that next infill well?” Desperation sets in. Production has fallen big time. Management is unhappy. Shareholders are furious. A few months ago, the Wall Street Journal reported that, through 2017, one operator had spaced its wells 330 ft apart, then increased this to 500 ft (see “A Fracking Experiment Fails to Pump as Predicted, B. Olson, July 4, 2019). But the Journal ofPetroleum Technology recently gave different numbers, now “450 ft or 600 ft” (see “Simple Well Spacing Calculations are Inaccurate and Costly,” T. Jacobs, November 2019). Sometime back, the present author recalls a smaller 200 ft. Or something like that. Whatever the specifics, the consensus is clear - too close a spacing may be too bad and too late. <...>

The year 2020 marks the 100-year anniversary of Conrad Schlumberger’s publication on electrical methods, a document that serves as the foundation of modern-day resistivity and induced polarization methods. These methods are now two of the most widely used geophysical techniques for probing the near-surface (upper few hundred metres of the Earth’s crust). Although originally developed for hydrocarbon and mineral exploration, their popularity in near-surface applications grew rapidly from the widespread recognition that subsurface electrical properties are often well correlated to physical and chemical properties of fluids within the pore space (e.g. saturation, salinity) and lithological characteristics (e.g. porosity, clay content) needed to understand a wide range of near-surface properties and processes.

This beautifully presented course manual supporting Snowden Mining Industry Consultants renowned course in Resource Estimation represents the culmination of more than 20 years of course refinements, revisions, improvements and further refinements. No doubt the manual will continue to be improved in the future as new information becomes available and new techniques are introduced. After all a course manual must be a dynamic, living document that remains relevant to the mining industry. <...>

Оценка минеральных ресурсов структурно-сложных и прерывающейся минерализации с применением нелинейной геостатистики: на примере изучения мезотермального золотого оруденения Северной Канады

An estimation of resources of structurally complex gold lodes and stockworks represents a challenging task for geoscientists due to the complex geometry of the lodes and discontinuous grade. In the present case study, the resource of a gold stockwork has been estimated by uniform conditioning after the lode has been subdivided into geostatistically defined domains using the indicator probability model.