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RQD: Rock Quality Designation & What Your Core Is Telling You
How to calculate RQD from drill core, what the classifications mean, limitations of the method, and how RQD feeds into rock mass classification systems like RMR and Q-system.
Apparent vs True Dip: Getting the Geometry Right in the Field
Why the dip angle you measure in a cross-section is always less than the true dip, the trigonometry behind the conversion, and when it matters for geological mapping.
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