Henverson.—Post-Tertiary History of New Zealand. 593 
of Banks Peninsula and the peat-beds 600 ft. below sea-level, penetrated by 
bores in the Christchurch area (85, p. 29 ; 88, p. 427 ; 97, p. 385), definitely 
oil-bore gravel occurs to a depth of 1,500 ft., and oxidized sands (88, p, 423) 
and clays to 1,800ft. below sea-level (41, p. 12). According to Speight, 
a submerged forest occurs near the mouth t Pareora River, and valleys 
near Timaru have been depressed below sea-level. All the larger streams 
entering the sea between Oamaru and Dunedin have infilled estuaries at 
their mouths. The drowned valleys of Otago т едм and the numerous 
inlets of this neighbourhood furnish undoubted oe ta of depression. 
The sea once penetrated through the lower Taieri Gorge into an inlet which 
is now occupied by the Taieri Plain, and of which Waihola Lake is a portion 
not yet filled to sea-level. Similarly, Lakes Kaitangata and Tuakitoto are 
infilled portions of an arm of a drowned valley. Between Nugget and 
Waipapa Points are numerous inlets and estuaries, of which Newhaven and 
Waikawa are the chief. The depression of Stewart Island is obvious, and 
on the north side of Foxeaux dein are Bluff, New River, and Aparima 
inlets. aiau River has cut a valley, three miles wide at present sea- 
ae through the deposits laid idi during the 200—300 ft. standstill. 
This it has since filled with gravel, the terraces bordering its flood-plain 
ieu; up to 30 ft. high. 
The West Coast fiords are drowned glacial valleys which are all decidedly 
shallower at or near their mouths than farther inland. The entrance ot 
Sutherland Sound is almost completely blocked with sand and gravel, and 
tidal waters enter only the lower end of Lake McKerrow, which is also a 
depressed glacial valley, with a floor, at its upper end, 450ft. below sea- 
level (3, p. 44). E the exception of Preservation Inlet, which nowhere 
appears i be more than about 300ft. deep, the floors of the fiords are 
from 800 ft. to more than 1,700 ft. below the surface of the sea. That the 
ers overdeepened their valleys to this extent is unlikely, and the bulk 
of the excavation was probably done when the land was about 1,500 ft. 
above its present level. The submarine bars have been explained as 
moraines deposited as the ice retreated, but they may have accumulated as 
coastal drift during ancient periods of standstill, or they may be formed of 
both deposits. There is no mention in the literature of moraine at the 
sea ends of Lake McKerrow and Sutherland Sound, which are thought to 
have been choked during the present period of inconsiderable movement. 
The immense amount of gravel carried to the sea by the peann 
rivers and distributed northward along the shore by the coastal drift h 
filled in the estuaries that at one time no doubt existed along the ibas. 
Ross Flat occupies an embayment, and beneath it gravels, apparently of 
fluviatile origin, have been penetrated by a shaft to a depth of 265ft. 
below sea-level (31, p. 24), and worked for gold to 191ft. Blacksand beach 
leads occurring below sea-level have been sluiced and elevated or dredged at 
several pon in the Okarito, Hokitika, Greymouth, Barrytown, and West- 
rt , and bores near the mouth of Waimangaroa River penetrated 
gravel and sand to a depth of 80 ft, without reaching solid rock (49, p, dli 
Haast (108, p. 112), noted a submerged forest a few miles west of Westport 
Small coves in granitic rocks rear Charleston appear to be drowned valleys, 
as Westhaven Inlet, at the northern end of the Island, is undoubtedly. 
