Page 189 - Microtectonics

178 6 · Dilatation Sites – Veins, Strain Shadows, Fringes and Boudins

▼
Fig. 6.22.
Theoretical model for the devel-
opment of strain fringes in co-
axial progressive deformation
around cubic and spherical core
objects in the case of face-con-
trolled and displacement con-
trolled fibres. Rigid and deform-
ing fringes are shown. In the case
of cubic core objects, the shape
of the fringe strongly depends on
the original orientation of the
core object with respect to the
opening direction of the fringe

Fig. 6.23. ▼
Natural strain fringe and its
simulation after Köhn et al.
(2001). a Natural strain fringe
with displacement- and face-
controlled fibres, and mixed
fibres. b Simulation of a fringe
that produces a similar pattern.
Face-controlled parts of fibres
(grey) mainly occur next to
a suture line. Scale bar in a is
0.8 mm. (Courtesy Daniel Köhn)