300 



Pedler's Creek, a distance of nearly two miles. Before this creek is reached, 

 however, there is a small outlier of the newer marine beds on the beach, but 

 above high-water level, which is fossiliferous, and yielded such typical forms as 

 Ostrea arenicola, Tate ; Laganum platymodes, Tate ; and Pecten antiaustralis, 

 Tate. This is the only known occurrence of rocks of this age between the 

 Aldinga cliffs and the area previously described, situated on the northern side 

 of Morphett Vale Creek. 



On the southern side of the sandhills (that occupy the low ground at the 

 mouth of Pedler's Creek) is another small but interesting outlier of the fossili- 

 ferous Miocene beds. It is probable that they have been preserved by a trough 

 fault that has brought them into contact with the broken edges of the Cambrian 

 strata. A small fragment of the underlying freshwater beds is exposed in a 

 washout at the back of the section, and, resting on these, is a very white argil- 

 laceous limestone which bears a close likeness to the Witton Bluff beds, and, 

 like the latter, is no doubt a bleached form of the less altered Aldinga Turritella 

 clays. The fossiliferous beds are about 20 feet in thickness, having a dip of 

 24° to the north-west. They form the main cliff for about 100 yards in length, 

 and pass out of sight on the northern side beneath the newer deposits. About 

 200 yards to the northward of this outcrop the same beds are seen, at low-water 

 level, in several parallel ridges that rise about a foot above the level of the 

 beach. Their slight elevation makes it difficult to estimate their angle of dip, 

 but they appear to have a higher inclination than the beds in the cliff section 

 and the dip is more westerly. One of these outcrops is an exact counterpart of 

 the dark-coloured Turritella clays of Blanche Point. The beds on the beach 

 are more fossiliferous than those in the cliffs and the fossils are better preserved. 

 Turritella aldingae, Tate, is in great numbers (as casts in the cliff beds but 

 with shells preserved in the outcrops on the beach) ; casts of Valuta sp., Cypraea 

 sp., and Dentalium sp. ; Pecten hochstetteri, Zittel ; Magellania sp. (crushed 

 fragment); large masses of Cellepora gambierensis, Ten. Woods; also the 

 imperfectly preserved (?) Retepora and (?) Cladocora contortilis, Ten. Woods, 

 occur, embedded in the clay, as in the Witton Bluff section. Many and various 

 spines of Echini are scattered through the bed, but no echinoid test was seen 

 in situ, although plates of Cidaris were found, and a fine example of Holaster 

 austraUae, Duncan, was picked up on the beach. 



Cambrian Beds in Section D. 



The Cambrian beds abut against the lower marine outlier, just described, 

 on its southern side, and, for about a mile in length, once more make the prin- 

 cipal feature in the sea-cliffs. The beds consist of purple and grey slates inter- 

 bedded with very strong whitish and fine-grained quartzites. The beds roll in 

 flexures up to a dip of 45° and are covered by a retreating cliff of the reddish 

 clays, while the latter are capped by a considerable development of a white, earthy 

 travertine, which is also set back from the face of the cliifs, so that, as a conse- 

 quence of the variable degrees of weathering, the cliffs consist of three distinct 

 faces and two ledges. 



Near the southern limits of the line of cliffs, just described, there is a small 

 cove that has been eroded on the axis of an anticlinal fold in the Cambrian 

 slates. The beds are almost clay-like in their softness, and, as they are excep- 

 tionally highly coloured, the place has been a rendezvous for the aborigines in 

 past times for obtaining red ochre for personal ornamentation and other 

 decorations. 



On the southern side of this little cove the Cambrian rocks make a low 

 point and once more disappear from view and are overlain by the freshwater 

 beds of the lowest member of the Tertiary succession, which, from this point. 



