5.3  Contour plots for an annular shear strain from 13.4 to 18

Thirteen pictures separated by time steps of 3 minutes were used for analysis of movie 4). 100 markers were digitised for the thirteen pictures. The Rf values increase locally to 1.5 along the shear bands and the microlithons are characterised by unstrained areas, although these areas shrink with the time and the strain gradient increases from the microlithons to the shear bands (C'). On the left side a strain concentration is visible with increasing deformation. The contour plots of Wn show super-simple shear in two directions in the S-C' fabric. At the start of the movie Wn varies along the shear bands. Wn at shear band tips show an anticlockwise rotation and that in the center a clockwise rotation. Values of 1 were localised around the shear bands and with progressive deformation the areas of super-simple shear shrink at the expense of a simple shear.