The camera and the interrogator Speak to exploration geologists and you will find two opposing views about what a geologist should do when observing outcrop or drill core in the field. Some seek merely to be unbiased objective recorders of what they see. Others observe the rock […]
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Look after your drill core: it’s a resource that keeps on giving Diamond drilling is always undertaken for the needs of the moment. But fresh-cut rock, in most cases, will last hundreds, if not thousands, of years. Drill core is a resource which can keep on giving […]
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Stereonet solutions for non oriented drill core Shawn Harvey of Saskatchewan sent me this email earlier this year: Hello again Roger, You previously helped me out with some alpha-beta stereonet solutions which worked great (thanks again!!). I am now looking into a slightly more complex stereonet issue. […]
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Using a stereonet to calculate strike and dip from alpha-beta angles in oriented drill core The attitude of a surface in oriented drill core can be determined by the measuring two internal core angles known as alpha (α) and beta (β). These numbers are then normally entered […]
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Sense of Movement Structures in Fault Zones. Part 3: Identification criteria Within or adjacent to a fault zone, various minor structures can be present that enable the sense of movement across the fault to be determined. These structures are often called kinematic indicators. In Part 1 of […]
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Sense of Movement Structures in Fault Zones : Part 2 – Examples Within or adjacent to fault zones, various minor associated structures can be present that enable the sense of movement across the fault to be determined. These structures are often called kinematic indicators. This is the […]
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Sense of movement structures in fault zones - Part 1, Theory Within or adjacent to fault zones, various minor associated structures can be present that enable the sense of movement across the fault to be determined. These structures are called movement or kinematic indicators. Faults are the host […]
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TARGETING DRILL HOLES It is a truism that ore bodies are rare and hard to locate. If this were not so, they would hardly be worth finding. Explorers search for them by drilling holes into the ground. A single drill hole produces a very small sample […]
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The Three Point Problem In a previous post (see here) I described how quantitative orientation data can be collected from from a single drill hole, even where the core is not oriented. In this post, techniques for collecting orientation data on planes are described when more than one […]
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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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