440 PROCEEDINGS OP SECTION E. 



the upward movement has been accompanied by earth blocks falling 

 in along fracture plains developed during the earth movements which 

 commenced at the close of the Miocene. 



Whether the Australian coast was subsiding at this time does not 

 appear to be known definitely, though it is realised that the eastern 

 coast has been undergoing a downward movement for a long period, 

 superseded by an upward movement now in places. In the earth 

 forms of New Zealand the latest movement that is recorded is an 

 elevation, but of unequal amount, in different parts of the land. This 

 is most clearly seen in the extreme south-west, where on the shore 

 of Foveaux Strait terraces reach to a height of 1,500 ft. above sea 

 level. Hutton has recorded gravel terraces and raised beaches at 

 various points and heights on the coast line extending north to the 

 Thames. Percy Smith noticed others in Auckland Harbour, though 

 only a few feet above sea level. 



Rock shelves are also to be seen in many places. At Ewing 

 Island, in the Auckland group, a veiy recent one is to be seen about 

 15 ft. above the present sea level. The flat granite tops of the Snares 

 Islands are certainly a iomyer level of marine erosion. The islets 

 lying off the north-east coast of Stewart Island also indicate an old 

 sea level from 50 ft. to 100 ft. above the present sea level. At 

 Dunedin there is a shelf 300 ft. above the beach. On the shore of 

 Rangitoto Channel, alongside of Lake Takapuna, near Auckland, a 

 well-formed shelf is to be seen 6 ft. above high water, and Dr. Bell 

 says that at the North Cape there is an indication of a recent upward 

 movement of a few feet. Practically all New Zealand geologists are 

 now agreed that the numerous river terraces on the west of the 

 Canterburj^ Plains are due to movements of elevation. These features 

 are not confined to Canterbury ; they are as clear in Otago and South- 

 land. In Nelson the effect of an upward movement is seen even more 

 clearly, for a rock terrace is distinct on the Wairoa and Roding Rivers 

 20 ft. above the present river bed. The terraces on the Rangitikei 

 and Waikato Rivers are also remarkable. This last movement has, 

 therefore, been widespread in the interior and on the coast, but 

 appears to have been greatest in the south. 



It is well known that within historic times a spasmodic movement 

 of important extent has been recorded in New Zealand. In 1855 the 

 shore of Wellington Harbour rose 5 ft. during a severe earthquake. 

 The effect was more pronounced on the coast line west of Wellington 

 Heads, and it apparently increased in amount westward, for at Cape 

 Palliser the rise was 9 ft. It is said by Lyall that there was a move- 

 ment of an opposite character on the south shore of Cook Strait. The 

 evidence of this is, however, less strong than for the movement near 

 Wellington. 



Volcanic Action. 



Whatever may be the real nature of volcanoes in the scheme of 

 Nature, it is universally agreed that their existence at any spot is an 

 indication of crusted disturbances or instability. It is thei'efore of 

 importance to consider their distribution with reference to the Tonga- 

 Kermadec ridge and trench. In Tonga itself the active volcanoes, 

 Tofua and Kao, with Latte and Falcon shoal are among the western 

 islands of the gi'oup. The eastern are noticeably free from volcanic 



