Oriented drillcore: measurement, conversion, and QA/QC procedures for structural and exploration geologists / Ориентированное бурение: процедуры измерения, преобразования и контроля качества для структурных геологов и геологоразведчиков

During core drilling, runs of core up to about three metres long are extracted from the core barrel. The extraction process rotates the core randomly, so that once the core is laid out in core boxes its original orientation is lost, although the orientation of the core axis is generally known. Various down-hole surveying techniques are available for this, and the common usage of 3-D modelling software has lead to holes being generally very well surveyed. <...>