474 Transactions. — Geology. 



About seven miles from Wairau Creek there is another 

 outcrop of the breccia. The strata near Deep Creek have a 

 southerly dip, which brings up the volcanic bed at the south 

 head of the bay. At the north head it forms the mass of the 

 cliff, and also a small island 50 yards from the shore, which is 

 completely composed of it. The actual thickness is nowhere 

 seen, as a fault occurs beyond the bay, but the bed must be 

 more than 30 ft. thick. It is rather coarser than at Chelten- 

 ham, and contains numerous Bryozoa. The weathering of the 

 ucper parts is very noticeable. The upper 8 ft. weathers to a 

 rich red earth with concentric markings (Plate XXXVIII. , 

 fig. 3). 



On the north bank of the Okura River there is an outcrop 

 of a coarse volcanic breccia interbedded with shale and sand-- 

 stone. In texture it resembles the Deep Creek bed, but it is 

 not more than 4 ft. in thickness. The dip takes it up above 

 the cliff-line. The Okura Eiver forms a kind of V with the 

 Wade Eiver, the apex being directed seawards. On crossing 

 the Wade Eiver one is at the foot of Whangaparaoa 

 Peninsula. 



Whangaparaoa Peninsula, thirty miles from Auckland, is 

 about thirty miles round. This journey had to be done in 

 a day along a rugged coast, where it was sometimes difficult 

 to get along the rocks, so that I had little time for observa- 

 tions. Unfortunately, too, being pressed for time, I omitted 

 the end of the peninsula from the journey, and this apparently 

 was the locality from which Hochstetter's section was taken. 

 The cliffs on the south are composed of hard sandstones with 

 layers of shale, and at intervals a volcanic breccia resembling 

 in all respects the Okura breccia is interbedded with these. 

 It is perhaps slightly coarser than at Okura, but the thickness 

 is very regular — about 4 ft. The first point at which I ob- 

 served it was in the cliff opposite Kohanui Island. Large 

 blocks have fallen from the breccia, which lies on a shale bed 

 about 30 ft. from the foot of the cliff. No doubt the shale has 

 become slippery, allowing large blocks of the hard breccia 

 to slide away and form an admirable protection at the foot 

 of the cliff. The fragments of lava contained in it are a 

 compact grey rock with feldspar phenocrysts. It is ap- 

 parently an augite-andesite, and resembles fragments from 

 Cheltenham breccia. At Korimai Bay there is a very similar 

 outcrop of the same bed, and there are occasional outcrops 

 of the bed on the northern shore, but part of this coast I 

 examined in twilight. Along the beach I noticed occasional 

 fragments, well water-worn, of augite-andesites. 



Mr. E. Wilson informs me that at Mahurangi Heads, 

 about ten miles to the north of the peninsula, there is an 

 outcrop of a very similar bed ; but it is coarser, lumps of lava 



