242 C. T. Trechmann — Glacial Controversy 



seems to carry great conviction, though I am not competent to offer 

 any useful opinion on this matter. 



Other New Zealand geologists appear to adopt an attitude of 

 neutrality, or so far as they have expressed any opinion on the 

 subject seem to lean towards the view that the glaciation was of 

 a localized and not of a regional character. 



The glacial or reputed glacial sections and boulders I have actually 

 seen in New Zealand are comparatively few, but in so far as they 

 affect the questions above-mentioned they are important and critical 

 ones. The evidence of a general nature dealing with the two 

 contending views has been so thoroughly put forward in the papers 

 quoted that to go into it would merely be repeating what has already 

 been written, so I shall confine myself to giving my own interpreta- 

 tion of the sections I visited. 



Taking the question of the North Island first, Professor Park says 

 in his Geology of Neio Zealand?- where he devotes many pages to a 

 detailed description of the various sections, " In the Pangitikei 

 watershed there is a glacial moraine of great extent composed of 

 andesitic blocks torn from the higher slopes of the volcano Puapehu 

 and transported across the Pangitikei divide into the lower Hautapu 

 valley. This conspicuous moraine sheet is spread over the denuded 

 surface of marine clays of Pliocene age." He speaks of this as the 

 Hautapu or older glacial drift and the Hautapu till. 2 



When I was in New Zealand in 1915 I heard that Professor. Park 

 had found one of these andesite boulders bearing striae which placed 

 its glacial origin beyond question. I mentioned this matter to him 

 when I had the pleasure of meeting him, and he kindly gave me 

 instructions as to where I could see the boulder. Professor Park has 

 recently described this boulder in detail, 3 and gives an excellent 

 photograph both of the whole mass and a nearer view showing the 

 scratches on it. 



This boulder bearing the scratches is of prime importance because 

 it seems to me that the question of the glaciation of the North Island 

 practically stands or falls with this boulder. If the scratches are 

 not glacial the boulder is not glacial, and if this boulder is not 

 glacial none of the others are glacial, and the chief evidence for 

 a glaciation in the North Island fails. 



I came away convinced that the scratches on the boulder are not 

 glacial, and that they could have been and were caused by other 

 means. I do not desire in any way to appear to take sides in this 

 controversy, but with due respect to Professor Park's opinion I must 

 say that I differ from him as regards the mode of origin of the 

 striations on this boulder. 



It is situated on the slope of a hill on the south side of the entrance 

 of a railway tunnel south of Mangaweka station, several hundred 

 feet above the deeply cut gorge of the Pangitikei Piver, and 

 about 35 miles south-south-east of the summit of Puapehu. It 

 measures about 14 X 8 x 6 feet, and must weigh about 35 tons. 



1 Geology of Neio Zealand, 1910, p. 183. 



2 Ibid., 1910, p. 205. 



3 Trans. N.Z. Inst., vol. xlviii (N.S.), pp. 135-7, 1915. 



