Geology Reference
In-Depth Information
patterns (Fig. 11.23b). Elsewhere, and more commonly, however, the cracks occur in distinct and
repeated arrangements. Polygonal cracking or weathering consists of a pattern of cracks, some as
much as 5 cm wide developed in a superficial shell or shells of rock: they extend to no more than
a few centimetres beneath the surface of boulders, blocks or platforms. They form orthogonal,
(a)
Figure 11.23.
(a) Hieroglyphs on granite surface at Daadenning Hill, near Merredin, southwest of Western
Australia.
(b)
Figure 11.23.
(b) Radial fractures on boulder at Corrobinnie Hill, northern Eyre Peninsula, South Australia.
