Geology Reference
In-Depth Information
(a)
(b)
Figure 7.9.
(a) Castle koppie at the Devil's Marbles, Northern Territory. (b) Map of locality. Note location
in valley bordered by bevelled quartzite ridges.
slopes (see Chapter 8) up to 5 m high in some of the valleys, and a platform standing 2-3 m above
the present scarp foot bordering the piedmont plains. The conical hills are, it is suggested, due to
intense weathering of fracture-defined blocks, the crests of which were exposed. The crests were
thus protected, but below ground weathering proceeded apace, especially in the near surface zone
