LATE PALAEOZOIC FOLDING IN THE HUNTER RIVER DISTRICT. 125 



intense, separated by long periods of peneplanation and 

 sedimentation in geosynclines and epeiric seas. 



R. T. Chamberlin (1) has remarked on tbe possible per- 

 iodicity of these movements and their relation to deform- 

 ative processes in other parts of the world. The close of 

 the Devonian in N.S.W. was marked by a period of pro- 

 nounced diastrophism/ 2 ) and during the epoch following on 

 to the beginning of the Mesozoic important orogenic 

 movements were going on in the North-eastern part of the 

 State. Benson (3) has shown that in late Carboniferous 

 times a strong crustal activity affected New England. The 

 Lower Hunter area does not seem to have participated in 

 this movement, unless the Hunterian disturbance (4> p - 282) can 

 be correlated with it. The work of Andrews^ in the New 

 England area emphasises the importance and magnitude of 

 the crustal upheavals in Permo-Oarboniferous times, and 

 it is possible that there was more than one period of 

 activity. Much of the elucidation of this problem depends 

 on the age of the Drake slates, the palseontological evid- 

 ence seeming to indicate a facies transitional between 

 Kuttung and Lower Marine or between Burindi and Lower 

 Marine, 1 although Walkom (6) has suggested the possibility 

 of continuous sedimentation from Lower to Upper Marine 

 time. It is definite that the diastrophism which affected 

 the New England area decreased in intensity southwards, 

 and as Sussmilch (7) has pointed out, the only expression of 

 corresponding movement in the Hunter River strata is the 

 existence of overlap of some beds on others. During the 

 latter part of the Permo-Oarboniferous period the mountain 

 building forces had a greater effect on the Hunter district, 

 producing a series of anticlines and synclines accompanied 

 by normal faulting. Of this folding the initial portion 

 occurred in pre-Newcastle time, when the Lochinvar anti- 



1 Verbal communication from Professor David. 



