214 PROCEEDINGS OF SECTION C. 



to Nelson and its reappearance again in New Caledonia. The 

 prevailing strike of the beds in the far north is, according to Clarke, 

 N.N.W. to S.S.E. — that is, in the direction of the general trend 

 of the peninsula. It is, according to Hector, also the trend of the 

 mineral veins of Cape Brett, to the east of the Bay of Islands. 

 The direction of the main axis of folding in the Coromandel Penin- 

 sula is, however, slightly more to the east. In Bulletin No. 10 

 (Geology of the Thames Subdivision) Fraser notes that the main 

 direction of folding in the pre-jurassic rocks is nearly parallel to the 

 trend of the Hauraki Peninsula, that is with the more northerly 

 of the two main lines of folding which are evident in New Zealand. 

 The quartz lodes of the area are, however, generally parallel to the 

 Ruahine-Southern Alps line of folding with its prevailing N.E. to 

 S.W. direction. In the same Bulletin reference is made to the main 

 faults of the area ; and the author endorses the generally accepted 

 statement that the Firth of Thames is a down-faulted area or 

 " graben," and that other main faults of the locality are connected 

 with it in origin. He also concludes that the rocks of the area have 

 been subjected to a tilting towards the south-east on an axis 

 running north-east. 



Bulletin No. 9 (The Geology of the Whatatutu Subdivision) 

 deals chiefly with the tertiaries on the east coast of the North 

 Island, to the north of Gisborne. The beds here are fairly flat 

 and slightly folded ; the axes of the anticlines that have been 

 recorded run generally north-east and south-west, though with 

 occasional local variations. Reference has been made earlier to 

 the finding of boulders of plutonic and gneissic rocks in a con- 

 glomerate in the locality. 



In Vol. XLII, Trans. N.Z. Inst., 1910, Dr. J. M. Bell again 

 refers to the formation of Wellington Harbour, and shows from 

 physiographical evidence that earth movements have taken place 

 within fairly recent times on a line running north-east up the 

 western side of the harbour, resulting in a differential movement 

 giving a throw of at least 500 feet to the south-east. He has also 

 suggested the probable existence of other faults running in approxi- 

 mately parallel directions ; but the available evidence in support 

 of his hypotheses is at present somewhat uncertain. 



Bulletin No. 11, by E. J. H. Webb, deals with the Mount 

 Radiant sub-division in West Nelson, north of the Buller River. 

 The oldest rocks, which are poorly developed, are of probable 

 Ordovician age, and are folded along a N.W. to S.E. line. They 

 are penetrated by granite intrusions of post-Ordovician and pre- 

 Miocene age, and overlain by Miocene sandstones, breccias, grits 

 and limestones, and later detrital deposits. The present physic- 

 graphical features of the area seem to be determined by a series of 

 faults which have produced sets of high level and low level blocks. 

 The main fault lines follow a N.N.E direction, and the largest fault 

 has a relative downthrow to the west of at least 4,000 feet. The 

 coast line is also probably determined by the presence of another 

 large parallel fault. The effects are, however, compUcatad by a 



