Geology Reference
In-Depth Information
Fig. 6.4 Artificial twinning
of calcite parallel to plane
ð
0112
Þ
produced by forcing a
knife-edge into a cleavage
rhomb at point a (derived
from the sketch in Fig. 516,
p. 210, from Dana
1932
)
α
Fig. 6.5 Section of strain
ellipsoid for mechanical
twinning. Section is normal to
intermediate principal strain
axis, a direction of no strain.
The plane of the drawing is
known as the ''shear plane''.
K
1
and K
2
are the circular
sections or planes of no
distortion
h
1
g
a
K
2
K
1
h
2