142 GEOLOGY MAITLAND-BRANXTON DISTRICT, 



land-area during Permo Carboniferous time. This leaves us with 

 two alternatives as to the position of the Lower Marine Sea, and 

 only detailed mapping of the areas mentioned can finally decide 

 which is the correct view. These alternatives are, (1) that a 

 land-mass constituted the north-eastern corner of New South 

 Wales, and this was cut off from the mainland by a long narrow 

 sea, the western coast of which was probably that shown on the 

 map( Plate x.); or (2), that there was a long narrow peninsula, 

 probably joined to the mainland somewhere between the Macleay 

 River and Tnverell, running in a general north-easterly direction 

 to the Tweed River district, and that the Lower Marine rocks of 

 northern New England and Drake were deposited in a large bay 

 connected with the ocean on its northern side. Of these two 

 alternative views, the former seems, to me, to be the more 

 probable. 



Towards the close of Lower Marine time, a slow pushing force 

 began to make itself felt from a direction about E. by N. This 

 may perhaps have been the first expression of the great move- 

 ments which culminated eventually in the extensive granitic 

 intrusions into the Permo-Carboniferous strata of New England. 

 The result of this movement, pushing against the mainland to 

 the west, was to elevate a belt roughly parallel to the old coast- 

 line, and to depress somewhat the belt in between this elevated 

 belt and the mainland.* The effect of this was the production 

 of a land-zone extending in an approximately S. by E. direction 

 from northern New England, and the depression of a zone 

 between this and the mainland. The amount of depression, how- 

 ever, was not sufficient to submerge the old N.N.W. mountain 

 range of Devonian and Carboniferous rocks near Tamworth, and 

 this divided the submerged zone in two. Thus, there were pro- 

 duced relatively long and narrow inland depressions, in which 

 the Greta Coal-Measures were deposited(Plate xi.). The presence 



* This is somewhat the same effect produced by placing a sheet of paper 

 flat ou a table, with one end against a fixed object, and pushing the other 

 end towards the fixed object. The first part of the paper to be elevated 

 is a belt somewhere about the middle of the sheet, and parallel to the edge 

 which is against the fixed object. 



