Other formats

    TEI XML file   ePub eBook file  

Connect

    mail icontwitter iconBlogspot iconrss icon

Geology of the Provinces of Canterbury and Westland, New Zealand : a report comprising the results of official explorations

The Ashburton

The Ashburton.

Of the rivers of glacier origin, the last which has its sources and its whole course in the present Province of Canterbury, is the Ashburton, the main source of which is situated on the eastern slopes of Mount Arrowsmith, issuing from the Ashburton glacier, 4832 feet above the sea level. For the first ten miles the river flows in a more or less open channel between the ranges, where it is possible to follow its bed on horseback to within two miles of the glacier. It here receives several tributaries, of which one at the beginning of the Ashburton gorge, draining the eastern slopes of the Potts range, is the most important. It afterwards enters a deep, rocky gorge, where the traveller has to follow the rocky shelves and glacier terraces several hundred feet above the river, emerging, after a course of five miles, upon the Upper page 215Ashburton plains. Here the river expands again, and passing diagonally through them, after flowing another five miles, it re-enters between the ranges, without its valley, however, once assuming the character of a gorge. Several tributaries, mostly furnished by small lakes lying between morainic accumulations, join the Ashburton on these plains. The most important of them is Clearwater creek, the united outlet of Lakes Tripp and Acland, which after a tortuous course of six miles, measured in a straight line, falls into the main river on the right bank, near the beginning of the so-called Lower Gorge. Another stream enters from the opposite side, draining Maori lake, and some other small tarns. The so-called Lower Gorge of the Ashburton is 12 miles long, with well defined terraces on both sides, above which the mountains rise to no considerable altitude. The River Stour is the most important affluent here. It drains the southern slopes of the high and precipitous Mount Somers range. After issuing from amongst the ranges, the river enters the Canterbury plains, where, owing to its lesser size, it forms only low terraces, and after a course of 35 miles reaches the sea, 21 miles south-west of the mouth of the Rakaia. Owing to the peculiar conformation of this portion of the Canterbury plains, the Ashburton is the only glacier river which receives any addition on the plains themselves, being first joined by two smaller affluents, the Bowler's and Taylor's streams, and afterwards, 11 miles from its mouth, by the Northern Ashburton, the most important of its tributaries, being fed by the drainage of the large block of mountains between the Southern Ashburton and Rakaia, and separated from the Southern Alps by the Ashburton plains.