279 



A GEOLOGICAL SKETCH-SECTION OF THE SEA-CLIFFS ON THE 



EASTERN SIDE OF GULF ST. VINCENT, FROM BRIGHTON TO 



SELLICK'S HILL, WITH DESCRIPTIONS. 



By Professor Walter Howchin, F.G.S. 



[Read September 13, 1923.] 



Plates XXII. to XXVI. 



CONTENTS. 



Page 



Section A. Brighton (Bore) to Black Point 280 



„ B. Black Point to Rocky Point 284 



„ C. Rocky Point to the Mouth of the Onkaparinga River . . . . 293 



„ D. From the Mouth of the Onkaparinga River to the Red Ochre Cove 299 



„ E. Red Ochre Cove to Snapper Point . . . . . . . . . . 301 



„ F. From a little South of Snapper Point to Sellick's Hill Beach Road 307 

 „ G. From Sellick's Hill Beach Road to the end of the Fossiliferous 



Tertiary Beds . . . . . . . . . . . . . . . . 307 



General Remarks .. .. .. .. .. .... .. .. .. 311 



Bibliographical References . . . . . . .... . . . . . . . . 313 



A few places of special geological interest and of easy access, on the eastern 

 margin of Gulf St. Vincent, have been carefully examined, especially for fossils, 

 and a considerable literature exists in relation to the same ; but, hitherto, there 

 has been no attempt to give a consecutive and complete section of what must be 

 regarded as one of the most interesting combinations of geological features to be 

 found in the southern portions of the State. 



The geological systems that appear in this line of section include the Cam- 

 brian, Permo-Carboniferous (glacial), various Tertiary horizons (both fresh- 

 water and marine), Pleistocene and Recent. 



With respect to the nomenclature of the Tertiary systems of South Aus- 

 tralia, the late Professor Tate classed the older marine series ["Aldingan," etc., 

 Victoria=:"Janjukian"] as of Eocene age; and the newer marine series, as of 

 Miocene age. Mr. F. Chapman and Professor J. W. Gregory, following the late 

 Professor McCoy, consider Tate's Eocene to be of Miocene age, and Tate's 

 Miocene to be Lower Pliocene (Chapman, F., 1914). This revised classification 

 has been followed in the present paper. 



To the northward of Marino (near Brighton) no beds older than Recent 

 are exposed along the coast. The shores are low and fringed by sandhills and 

 mangrove swamps which continue to the head of the Gulf, giving evidence of 

 recent elevation of the shoreline to the extent of about 16 feet. 



