NOTES on the GEOLOGY of KING ISLAND, BASS 



STRAITS. 



By F. Debenham, b.a., Deas-Thomson Scholar in Geology, 



University of Sydney. 



[Communicated by W. G. Woolnough, d.sc, f.g.s.] 



[Read before the Royal Society of N. S. Wales, November 2, 1910.] 



Contents. 



Introduction and Previous Literature. 



Physiography. 



Geology— The Sedimentary Rocks. The Eruptive Rocks. 



Economic aspects of the Geology. 



Petrological Notes. 

 Introduction.-King Island is situated at the western 

 end of Bass Strait, and is midway between the mainland 

 and Tasmania, its distance from either being about 55 miles. 

 The island is roughly trapezoidal in outline with its longer 

 axis in a meridional direction, its extreme length is 40 miles, 

 extreme breadth 16 miles, and area approximately 400 

 square miles. It is therefore, with the exception of Flinders 

 Island, the largest island in the Straits, and a rough idea 

 of its size may be gathered from the fact that, looking at 

 Bass Strait from due west, King Island blocks up rather 

 more than a quarter of its western entrance. 



: relationships to bee 



nsidered 



later, it is necessary to draw attention to the fact that the 

 island is to the north-west of Tasmania, and that if we 

 produce the line of the west coast of Tasmania it will pass 

 through King Island and reach the Victorian coast a little 

 to the west of Cape Otway. The island possesses a remark- 

 ably equable climate, but it is subject to heavy westerly 



