126 PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND, 



Hill area, while the Gre,y Phase occupies one-quarter of 

 the Enoggera area and the whole of the two outcrops at 

 the Kedrou Brook area. Further, the latter phase is usually 

 restricted to the more deeply dissected or more central 

 portions of the Enoggera area, the highest points and 

 peripheral portions being almost invariably occupied by 

 the aplitic, fine-grained and "sandy" granites which form 

 a distinct type of the Pink Phase. The vertical section in 

 the central part of the Enoggera area, obtained by descend- 

 ing into the valley of the Enoggera Creek from the heights 

 lying to the north, gives in descending order the following 

 sequence : — 



Aplitic and "sandv" granites"! p. , p. 

 Typical Pink Phase /""^ ^^''• 



Pink Phase with included fragments of Grey Phase. 

 Typical Grey Phase. 



A similar sequence is often, but not always, found in 

 passing from the periphery towards the centre of the area. 



This arrangement of the dark and light phases seems 

 at first glance to suggest a differentiation into two main 

 types as the result of gravitative separation, but a closer 

 study of the relationship of the phases does not support 

 such an hypothesis. 



The only indications which have been noted M'hich 

 suggest any difference in the time of intrusion of the two 

 phases appear at first sight to be contradictory. 



In some sections the Grey appears to intrude the Pink 

 Phase as dykes, but in many other sections it is definitely 

 surrounded by the Pink Phase and forms irregular inclu- 

 sions or "segregations" of very variable size. While some 

 of the smaller of these are undoubtedly segregations in the 

 fitrict sense of the word, the vast majority of the larger ones 

 appear to be fragments caught up by the enclosing magma. 



There is thus some evidence that part at least of the 

 Grey Phase is later in age than the Pink, but the weight of 

 evidence points to the Pink as being the later phase. These 

 two groups of evidence, though apparently contradictory, 

 may perhaps be reconciled in the following way : — The 

 Pink appears to have broken through the Grey rock, carry- 

 ing fragments of varying size with it. Later the under- 



