Measuring Structure in Non-Oriented Drill Core My drill core is not oriented. How do I measure structure? Down-hole orientation surveys record the deviation of a drill hole from its initial azimuth and inclination. However, the solid stick of drill core (sometimes, not so solid) recovered from a […]
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The Specific Gravity (SG) of a substance is a measure of its density. It is expressed as the ratio of the weight of a given volume of the substance compared to the weight of an equal volume of a reference substance – usually water [1] . An […]
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Six rules for alpha beta measurements in drill core It is always better to know the orientation of planar structures at the time of logging rather than at some later date when the structure that was measured is long forgotten and the core returned to its stack in […]
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This post, the third part of a series (for parts 1 and 2 see here and here), is about the appearance of common geological structures on the surface of diamond drill core. Visualising complex objects in three dimensions isn’t easy, although geologists are better at this than most. Two dimensional […]
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MAKING SENSE OF 2D DATA – PART 2: FOLDS This post is the second of three parts (for parts 1 and 3, see here and here) and describes the different appearances which folds can have depending on the orientation of the surface on which they are exposed. […]
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Diamond drilling of a prospect typically goes through two phases. The required geological inputs for the two phases are different. The first phase comprises initial exploration drilling ‑ the target generation and target drilling exploration stages. In these stages drilling is aimed primarily at a geological understanding […]
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The camera and the interrogator How odd it is that anyone should not see that all observations must be for or against some view if it is to be of any service. Charles Darwin, 1870 Speak to exploration geologists and you will find two views about what a […]
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Vergences and fractals Field geologists have long known that the style and relationships of structures seen in a hand specimen, outcrop or drill core can mimic the style and relationships of much larger structures that formed during the same deformation but occur at the scale of a geological […]
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There are many, many times more prospectors and geologists exploring for mineral deposits than there are ore bodies to be found. It is entirely feasible for a competent explorationist to go through a career and never be able to claim sole credit for an economic mineral discovery. It […]
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There are two ways of measuring structures in oriented diamond drill core. The first is to set up the core in a core frame (often called a “rocket launcher”) so that it lies in the same orientation as it did when it was in the ground; the […]
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