Geology Reference
In-Depth Information
Table 12.1.
(
Contd
)
Granite
Other lithologies
Minor forms (
Contd
)
Fonts
Catalonia, Galicia, and central Spain; Portugal
Basalt - Falkland/Malvinas islands
Sandstone - Talia, western Eyre Peninsula, SA;
Palmerston, South Island, New Zealand; Cape
Paterson, eastern Vic (all coastal); Colorado
Plateau, Utah
Plinths
Eyre Peninsula, SA; Zimbabwe
Sandstone - Talia, west coast of Eyre Peninsula, SA
Pedestal rocks
Sahara; Appalachians, USA; Sierra de
Basalt - Death Valley, California
Guadarrama, central Spain
Dolomite - Ciudad Encantada, Spain
Sandstone - Kimba, northeastern Eyre Peninsula, SA
A-tents
Eyre Peninsula, SA; WA; Kulgera, NT
Limestone - NSW
Sandstone - Utah, Wyoming, USA
Triangular wedges
Eyre Peninsula, SA; Mariz, Galicia, Spain; Yilgarn
Conglomerate - Baxter Hills, northeastern Eyre
Block, WA
Peninsula, SA
Dacite/rhyolite - Gawler Ranges, SA
Polygonal cracking
Eyre Peninsula, SA; Mt Magnet, WA; Galicia,
Sandstone - Flinders Ranges, SA; Litchfield, NT;
Catalonia, Spain
Fontainebleau, France; Colorado; central Spain
Orthogonal cracking
Mt Magnet, WA; northern Portugal
Schist - Galicia, northwestern Spain
Speleothems
Eyre Peninsula, SA; Kulgera, NT; Mt Magnet, WA;
Conglomerate - Baxter Hills, northeastern Eyre
Galicia, Spain
Peninsula, SA
Limestone - numerous sites
Sandstone - Darwin area, NT; Flinders Ranges, SA
States of Australia: NSW - New South Wales, NT - Northern Territory, Qld - Queensland, SA - South
Australia, Vic - Victoria, WA - Western Australia; USA - United States of America.
mechanism appears to be at work in sandstone terrains, with the development of cliff-foot caves
and shelters, as for example at Ayers Rock (
Fig. 12.4a).
Cupolakarst is similar, and is also con-
verted to towerkarst or turmkarst (Fig. 12.4b) as a result of marginal weathering and steepening.
Some of this solution takes place beneath the soil surface but also finds surface expression in
swamp slots (Fig. 12.4c).
Many, perhaps most, granitic inselbergs appear to be two-stage forms based on massive com-
partments. But some are an expression of lithology (Chapter 6) and many non-granitic residuals
are of this type. They are upstanding by virtue of their development in resistant rock. Thus, The
Pinnacles, near Broken Hill, in western New South Wales
(Fig. 12.5a)
are upstanding by virtue of
the presence of discrete masses of quartzite which confer a measure of resistance on the otherwise
weak schists into which they are injected and in which the adjacent plains are eroded. Some well-
known isolated steep-sided hills, such as the Glasshouse Mountains of southeastern Queensland,
Ship Rock, New Mexico (Mueller and Twidale, 1988), and Wase Rock, northern Nigeria, are vol-
canic plugs (Fig. 12.5b). Again, Curtinye and Barna hills are low quartzitic domes near Kimba on
northeastern Eyre Peninsula, South Australia. Their domical form reflects the development of
rudimentary sheet fractures which cut across a steeply-dipping foliation, but the resistance of these
