OCT 2 1901 



Suggestions on the Origin of the Salt 

 Lagoons of Southern Yorke Penin- 

 sula. 



By Walter Howchin, i'.G.S. 



[Read December 4, 1900.] 



Introductory. 



The physical features of the country forming the "ioot," 

 or southern portions of Yorke Peninsula, are very singular 

 and interesting. Taking the latitude of Stansbury as a 

 northern limit, the district includes the Hundreds of 

 Dalrymple, Melville, Moorowie, Parawurlie, Coonarie, 

 Carribie, and Warrenben, extending about forty miles by 

 twenty miles, or an area of 800 square miles. Throughout 

 this considerable extent of country there are no rivers or 

 running streams, and, consequently, the drainage of the land 

 finds no outlet to the sea. Under such conditions it follows, 

 as a matter of course, that the inland centres of drainage 

 become the repositories of saline deposits from the concen- 

 trated mineral substances in the waters, but there are special 

 features pertaining to the physiography and geology of ths 

 country which makes the origin of the lagoons a subject of 

 considerable interest. 



The unusual feature of hundreds of saucer-shaped de- 

 pressions, irregularly scattered over most of the country 

 named, have to be accounted for. The official maps, on a 

 scale of one inch to the mile, record no less than 200 within 

 the district, but the maps do not include a vast number of 

 minor depressions which are frequently met with in travelling 

 through the country, and which may or may not contain 

 saline deposits. In a recent visit to the locality I observed 

 many such areas, which do not rank as lagoons ; they receive 

 but little drainage, ,and the bottom, instead of being a lake, 

 support a saliferous flora. Wliatever may have caused these 

 remarkable supei^cial depressions, it is evident they have 

 had a common origin, and the agency that has produced these 

 results must have operated over a wide extent of country. 



T'he Salt Lagoons not of Marine Origin. 



It would be an easy solution of the difficulty if we could 

 explain these scattered saline areas as the remnants of a re- 

 treating sea, and some of the phenomena under observation are 



