416 Transactions. — Geology. 



The moraines of glaciers are also found in the neighbourhood 

 of Lake Eotoiti, and in the Takaka district. 



While we have good reasons for believing that the sur- 

 rounding district was once much more elevated than it is at 

 present, we have abundant evidence to prove that it was once 

 far below the level of the sea. Beneath the glacial deposit to 

 which reference has already been made there lies a series of 

 stratified rocks, which, by their lithological character, and by 

 the fossils which they contain, give unmistakable proof of a 

 deep-sea origin. These rocks consist of sandstones and clays, 

 and many of the fossils found embedded therein are those of 

 species now extinct. Some of the lower members of this series 

 are w^ell developed in the Port Hills. When walking round 

 the rocks one is obliged to tread on the upturned edges of the 

 lower members of this series, known as the Lower Miocene 

 formation ; while in the cliffs above, especially near the basin, 

 the rocks may be seen dipping into the hill at an angle of 

 about 50°. These rocks, when formed, must have been laid 

 down in a horizontal position; hence their- present upturned 

 condition must have been brought about by a considerable 

 amount of upheaval in the earth's crust. Numerous fossils 

 may be found in the above-mentioned rocks, but owing to de- 

 composition it is very difficult to get perfect specimens. A few 

 good ones were found in the tunnel driven by Mr. Brown in 

 his search for coal. 



Passing from the Port Hills to Eichmond another set of 

 rocks is met with, known as the Wairoa series. These rocks 

 extend from the hills about Eichmond to the Wairoa Gorge. 

 They belong to what is known as the Triassic formation, and 

 are older than the Miocene deposits of the Port Hills. Their 

 relation to the rocks of the Port Hills is shown on the sketch, 

 where the rocks of the Wairoa series are seen to dip below 

 those of the Port Hills, while the Port Hills series forms what is 

 known to geologists as a synclinal arrangement. The Wairoa 

 formation is exceedingly rich in fossil remains, some of the 

 hills above the gorge being literally masses of fossils. They 

 may be found in the bed of the river just before entering the 

 gorge, and on the hill-slopes this side of the river, as far north 

 as Eichmond. It is the study of these fossils that has led to 

 the determination of the age of the rocks in which they are 

 embedded. Monotis saUnaria and Mytilus inohlcmaticus are 

 the most common. Mention is made in the " Outline of New 

 Zealand Geology " of teeth having labyrinthodont characters 

 having been found in this formation. This being so, we may 

 well suppose that, while these rocks were being deposited in 

 the shallow seas of that age, amphibious creatures of con- 

 siderable size disported in the lagoons, or basked upon the 

 mud-flats. 



