The Heart of the Southern Alps, New Zealand Author(S): James Mackintosh Bell Source: the Geographical Journal, Vol
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The Heart of the Southern Alps, New Zealand Author(s): James Mackintosh Bell Source: The Geographical Journal, Vol. 30, No. 2 (Aug., 1907), pp. 181-197 Published by: geographicalj Stable URL: http://www.jstor.org/stable/1776627 Accessed: 25-06-2016 10:17 UTC Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at http://about.jstor.org/terms JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Wiley, The Royal Geographical Society (with the Institute of British Geographers) are collaborating with JSTOR to digitize, preserve and extend access to The Geographical Journal This content downloaded from 132.203.227.62 on Sat, 25 Jun 2016 10:17:08 UTC All use subject to http://about.jstor.org/terms ( 181 ) THE HEART OF THE SOUTHERN ALPS, NEW ZEALAND. By JAMES MACKINTOSH BELL, Director, Geological Survey, N.Z. INTRODUCTION. THE central part of the Southern Alps, which includes the elevated country surrounding the magnificent peak of Mount Cook, presents many features of remarkable interest to the glaciologist and physiographer, and exhibits an area of country of rare charm to the observant alpinist and explorer. This part of the Southern Alps encloses, in addition to Mount Cook, the lofty peaks of Darwin, Malte Brun, Hochstetter Dom, Mount Elie de Beaumont, Mount de la Beche, Mount Haidinger, Mount Lendenfeld, the Silberhorn, Mount Hector, Mount Tasman, Mount Stokes, and Mount Sefton, all over 9800 feet in height, and rising, clad in perpetual snow, amid spacious fields of neve, from which emanate most of the great glaciers of New Zealand. These peaks represent the highest though not the most inaccessible country in New Zealand, and all stand near the island divide. A view obtained from various points of vantage on the divide discloses to the east and west most of the salient physical features of this interesting part of the country. Towards the west is visible the rapid descent of the country towards the Tasman sea; the rugged snow-clad peaks can be seen to be, near at hand, replaced by mountains with snow only on their summits and with their lowest slopes thickly wooded. These give way farther to the westward to wooded hills free from snow which close to the sea pass abruptly into flat or rolling lowlands, covered with dense forest. Towards the east the descent of the country is also rapid, but not nearly so much so as on the western side. The mountains gradually decrease in altitude, and are finally replaced by the rolling treeless stretches of the Mackenzie and Upper Waitaki plains, surmounted by an occasional outlying mountain. The sparseness of forest on the eastern side of the Alps stands in marked contrast to the western side, and only at a few sheltered spots along the lower mountain slopes, near the river courses, are visible the groves of stunted trees. THE GREAT TASMAN SYSTEM. Two sections across the Southern Alps-one by the Tasman river, Hooker glacier, Fitzgerald pass, and the Copland valley, and the other by the Tasman glacier, Graham's saddle, and the Franz Josef glacier- will illustrate some of the most striking features of this interesting glacial area. The longest and widest glacier in New Zealand is the great Tasman glacier, which has a length of 18 miles from its source at the base of the Hochstetter Dom to its terminal face, and a maximum width opposite the No. II. AUGIST, 1907.] o This content downloaded from 132.203.227.62 on Sat, 25 Jun 2016 10:17:08 UTC All use subject to http://about.jstor.org/terms 170" 171' t)kari.to|^) ^ \^-r Sketch Map .. to i'strate WTiad THE GLACIATION roa around Gib MT COOK 0\ Scale .... 111.000.000 .... or llnch o -15-78Stat o iles Gil espie , Bcights t, feet , " //.. ~:g^ ^^ ^ ' !'=^ ^^ \tr:CP- /"i~ ~ -. e- oc-b ,.~,_. ,(NEW ZEALAND ~/ ~ aa stL i~~~~~~~~~~~~~~~~~~~~~?r t " ) aa ( 2 gton Cook rostc ;'* ;[3' n 'dU i s ~~~~~~~9 " .t~~~~~~~~~~~r 44 44 C\I QI ^\w\^/b~~~~~~~~~~~ 45~~~~~~~eJ~ exPyM_0 1a rin . zo hurch 1-1 1r'^^~~~-./ - /' \, ~~~~~~h I~~~~~~~~~~~~~ei j '.C?r,, ? 7, \\ ^""' ^^\ J' f / ^^- / (If 170' 171' This content downloaded from 132.203.227.62 on Sat, 25 Jun 2016 10:17:08 UTC All use subject to http://about.jstor.org/terms THE HEART OF THE SOUTtHEN ALPS, NEW ZEALAND. 183 mouth of the Murchison river, later to be described, of 2 miles. From the terminal face of the Tasman glacier flows the river of the same name, which enters Lake Pukaki, after a course of about 231 miles. For this distance the stream anastomoses in many channels, through a broad U-shaped valley. The various streams are constantly changing their courses-a condition which, with the many quicksands, renders the river a very difficult one to ford. The river flat through which the various distributaries of the Tasman ramify is about 4 miles wide, on either side of which low morainic hills stretch to the base of the mountains- the broken Leibig range on the north-east, and the rugged slopes of the Ben Ohau range on the west. THE KARANGAMA RIVER. From 4 to 6 miles below the terminal face of the Tasman glacier the Tasman river receives the distributaries of the Hooker river-a wild turbulent stream formed by the union of the water from the Hooker and Mueller glaciers. Lake Pukaki, which has a length from north to south of 8 miles, and a width in the opposite direction of 31 miles, had formerly a much greater northward extension, its basin having been filled by the masses of debris brought down by the Tasman river. The outlet of Lake Pukaki is by the Pukaki river at its extreme south- western corner, where the river flows through thick masses of the terminal moraines deposited by the ancient Tasman glaciers. Lake Pukaki owes its origin to the damming by these moraines of the broad Tasman trough, probably formed by glacial planing along a pre-existing o 2 This content downloaded from 132.203.227.62 on Sat, 25 Jun 2016 10:17:08 UTC All use subject to http://about.jstor.org/terms 184 THE HEART OF THE SOUTHERN ALPS, NEW ZEALAND. river channel. Many phenomena testify to the former great extension of the Tasman glacier-the terminal and lateral moraines spreading far out on to the Mackenzie and Upper Waitaki plains; the ancient glacial terraces deposited on the slopes of the Ben Ohau and Leibig ranges, the highest of these being probably about 1500 feet above Lake Pukaki, but farther north occurring at greater altitudes; and the steep generally smooth lower slopes of the bordering ranges, especially towards the present terminal face of the Tasman glacier. The differences of level between the lateral moraines of the ancient Tasnan glacier is a somewhat remarkable feature. The Tasman Glacier Proper. The Tasman glacier, which is longer than any single glacier in the Swiss Alps, though now vastly inferior in size to its former magnificent proportions, is still a very splendid ice-stream. In its lower reaches it is bordered by the Leibig range on the east, and by lesser peaks of the Mount Cook range on the west. Above the entrance of the Murchison the rugged snow-clad slopes of the Malte Brun range and Mount Darwin on the east, and the stately peaks of the island divide and Mount Cook on the west, surround the great glacier. From the east the most prominent entering stream is the Murchison. The terminal face of the Murchison glacier is about 1- miles above the junction with the Tasman, and most of the water which flows from it continues down along the eastern side of the Tasman ice and enters the river just below the snout of the Tasman glacier. The Darwin glacier flows into the Tasman from the east, between Mount Malte Brun and Mount Darwin. The largest tributary glaciers entering from the west are the Ball, Hochstetter, Haast, and Kron Prinz Rudolf, which flow from spacious snow-fields amid the mighty peaks of the island divide. These glaciers will be described later. Towards the lower part of the Tasman glacier numerous small streams of water descend in abrupt waterfalls from small U-shaped hanging valleys perched high on the mountain-sides. They flow from ice-blocks on the Leibig and Mount Cook ranges, and probably entered the Tasman glacier with an even gradient during the period of its maximum extension. The Hochstetter Dom has a very steep descent to the Whymper glacier, at the head of the Wataroa river, which flows to the west coast, but a comparatively gradual inclination to the Tasman glacier on the eastern side of the Alps. Below the huge bergschrund, which almost completely engirdles the summit of the Hochstetter Dom, the ice of the upper part of the glacier is remarkably smooth for about 4 miles, where crevasses disposed almost at right angles to the course of the glacier first become prominent, and from here thickly seam the ice for 4 or 5 miles. In the lower part of the glacier, where the moraines completely shroud the ice, crevasses are not especially evident, though the surface of the This content downloaded from 132.203.227.62 on Sat, 25 Jun 2016 10:17:08 UTC All use subject to http://about.jstor.org/terms THE HEART OF THE SOUTHERN ALPS, NEW ZEALAND.