(a) Boulder or shingle beach at Windmill Bay, Kangaroo Island, South Australia, composed of
released granite corestones. (b) Fitted and polished boulders at Windmill Bay.
domical, but off Cape Wilson, southern Victoria, both nubbins and bornhardts form islands ( Fig.
12.18) . Some are probably upstanding by virtue of their low fracture density, like Remarkable
Rocks on the southwestern coast of Kangaroo Island, but others, like those of Encounter Bay, in
South Australia, are an expression of lithological contrast, for the granite masses forming islands
and headlands are intrusive into schists and gneisses where have been preferentially weathered and
eroded by epigene or marine agencies, or by both. Flutings exposed on granite blocks near Hillock
Point, on southern Yorke Peninsula, South Australia, predate the dune calcarenite from beneath which
they are being exhumed, and may be of epigene provenance. Minor Kluftkarren exposed in the
coastal zone at Point Brown, west coast of Eyre Peninsula, give rise to an assemblage comparable