Stereonet Vizualization in Gocad

in: Proc. 29th Gocad Meeting. Nancy

Abstract

Stereonets are used to visualize the orientation of lines and planes in 3D by projecting them onto the planar image of the lower (or upper) hemisphere. Absolute positions of the lines and planes are not considered, but only their directions given by dip and dip direction for lines, and dip and azimuth for planes. Three types of diagrams are classically used: equal-area projection for the Schmidt stereonet, equal-angle projection for the Wulff stereonet, azimuthal and dip distributions for the Rose histograms. This paper describes the representation of lines and planes on the different diagrams, with the following features: selection of families of lines and planes to generate regions on points, lines, surfaces, visualization of densities of orientation data (represented by points on the diagrams), computation of a mean direction and dip of a group of lines or planes, computation of a mean plane passing by a group of lines. This work could be useful to both mineralogists working on crystal faces orientation, and structural geologists working on structural model building or fractures networks.

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    BibTeX Reference

    @INPROCEEDINGS{Merland2009a,
        author = { Merland, Romain and Caumon, Guillaume },
         title = { Stereonet Vizualization in Gocad },
     booktitle = { Proc. 29th Gocad Meeting. Nancy },
        volume = { 29 },
          year = { 2009 },
      abstract = { Stereonets are used to visualize the orientation of lines and planes in 3D by projecting them onto the planar image of the lower (or upper) hemisphere. Absolute positions of the lines and planes are not considered, but only their directions given by dip and dip direction for lines, and dip and azimuth for planes. Three types of diagrams are classically used: equal-area projection for the Schmidt stereonet, equal-angle projection for the Wulff stereonet, azimuthal and dip distributions for the Rose histograms. This paper describes the representation of lines and planes on the different diagrams, with the following features: selection of families of lines and planes to generate regions on points, lines, surfaces, visualization of densities of orientation data (represented by points on the diagrams), computation of a mean direction and dip of a group of lines or planes, computation of a mean plane passing by a group of lines. This work could be useful to both mineralogists working on crystal faces orientation, and structural geologists working on structural model building or fractures networks. }
    }