hand, beyond this gully, rises a bold, rocky hill which contains 
half of a huge, broken, anticlinal fold. We may call it Anticline 
Hill. At the foot of this rock face there is a well-chosen look-out, 
from which beautiful views of the gulf and plains may be 
obtained. Somewhere near the foot of the anticline (upfold), 
there must be an east-west fault. The rocks of the anticline are 
a hard quartzite ; wherever quartzite occurs we get rugged hill- 
sides or steep cliffs, quite different in character from the hillsides 
and cliffs in the softer phy Hites. 
Just past the parking place, the bold mural scarp of the 
main Morialta Cliffs comes into view. These consist of almost 
horizontal quartzites, strongly jointed with heavy talus slopes. 
The rock faces are beautifully coloured by lichens. Framed in 
the native vegetation, and varied by the few exotics planted in 
the valley bottom, these cliffs form a striking sight. A footpath 
leads across the creek to the left here, and one may wander away 
up along the tops of the cliffs, and on up to the top of Reids 
Hill (just above the cliffs, 1,375 feet), and so on by winding 
paths to the remote and rarely visited Hikers Hill (1450 feet) 
in the extreme northern part of the reserve. 
Both the quartzites and the phyllites (slates, etc.) belong 
to the Adelaide series of rocks, and were laid down in shallow 
seas in the long-distant past (Cambrian or Upper Pre-Cambrian), 
in the dawn-time of the world of living things. The phyllites 
were made of finer muds, with occasional limestone bands, and 
these have been profoundly altered by pressure and heat exerted 
upon them in crustal movements of the earth during the vast 
period that they have been in existence. No definite fossils have 
been found in such rocks, though it was one of the dreams of the 
late . Sir Edgeworth David that convincing evidence of such 
fossils would be found — a dream that may yet be realized. 
The quartzites were of coarser material, originally sand- 
stones. That is to say, they consisted of grains of sand (quartz). 
In the course of the ages the passage of solutions through these 
rocks has caused all the spaces between the sand-grains to be 
filled by quartz, thus producing a very dense, resistant rock. The 
alternation of the softer phyllites with the harder quartzites gives 
character and variety to this valley — gentle slopes and rounded 
hills where the phyllites occur, rugged slopes and cliffs where the 
quartzites outcrop. 
In places the rocks have been folded ; one anticline (upward 
fold) has been pointed out. Farther upstream there is a syncline 
(downward fold), also in the quartzites, on the southern valley 
wall at the site of the Giant's Cave. The main quartzite band 
gives rise to the First Fall and the Second Fall, while a narrower 
and higher belt of quartzite causes the Third Fall. 
Paoe Nineteen 
