Archive for the ‘Sterenet Solutions in structural geology’ Category

Stereonet validation of structural measurement in oriented drill core

Stereonet validation of structural measurement in oriented drill core

Summary Measuring the attitude of structures in drill core requires fully oriented core. But the tools for orienting core that are currently available to drillers often fail, especially with small core diameters (NQ or less) and where the rock has fissile surfaces within it. As these failures […]

Read more

Stereonet solution for non-oriented core

Stereonet solution for non-oriented core

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. […]

Read more

A stereonet solution for alpha beta angles in oriented drill core

A stereonet solution for alpha beta angles in oriented drill core

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 […]

Read more

The Three point problem: Calculating strike and dip from multiple DD Holes

The Three point problem: Calculating strike and dip from multiple DD Holes

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 […]

Read more

Measuring Structure in Non-Oriented Drill Core

Measuring Structure in Non-Oriented Drill Core

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 […]

Read more

Six rules for alpha-beta measurements in drill core

Six rules for alpha-beta measurements in drill core

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 […]

Read more

Using Stereonets

Using Stereonets

  Using Stereonets Cheap, versatile, reliable, compact, robust, ultra lightweight and does not need any batteries: there should be a stereonet in every geologist’s field kit. A stereonet is a tool (a type of nomogram[see footnote 1]) that allows the attitude of planes and lines in three-dimensional space […]

Read more

Measuring Structures in Oriented Core

Measuring Structures in Oriented Core

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 […]

Read more