14 T. W. E. DAVID. 



and banded jaspers strike in a N.W. direction through the 

 King Leopold Range to King's Sound. This belt of meta- 

 morphic rocks is 10 to 30 miles wide and 120 miles in length. 

 The Devonian rocks in the central and eastern part of the 

 Kimberley region have been folded in broad open folds on 

 axes which trend in a N. E. and S. W. direction. The 

 Carboniferous (Permo-Carboniferous Rocks) have not been 

 folded, but merely tilted. 



In regard to the Devonian rocks of the Kimberley district 

 Mr. Hardman estimated their thickness at nearly 11,000 

 feet, and Mr. H. P. Woodward describes these Devonian 

 rocks as striking N.E. and S.W. The question that obvi- 

 ously here suggests itself, is do these fold troughs of the 

 central and eastern part of Kimberley, such as those of the 

 Carr-Boyd Ranges, Saw Ranges and Lubbock Range meet 

 Pre-Oambrian folds of the King Leopold Range in linking 

 or in syntaxis. These trend lines from S.W. to N.E. agree 

 in general direction with the folding of the Devonian Rocks 

 of the Burdekin district as well as with one of the two 

 directions of folding on the Gilbert Gold-field of Queensland. 

 From a letter received from Mr. Gibb Maitland it would 

 appear probable that these two directions of folding at 

 Kimberley in West Australia form part of a syntactic arc, 

 and they may therefore provisionally be grouped as such. 

 At present the evidence as to the folds being symmetrical 

 or asymmetrical in this region is insufficient. One cannot 

 therefore as yet arrive at a definite conclusion as to the 

 sense in which the folding force has operated. 



That we know so much already about the structure lines 

 of West Australia, more probably than we know about 

 those of any of the other States of the Commonwealth, is 

 due chiefly to the enthusiastic and sustained efforts of Mr. 

 A. Gibb Maitland and his colleagues, notably Mr. H. P. 

 Woodward, Mr. E. T. Hardman and others who have toiled 



