Kerguelen Islands / Islands of DesolationThe Kerguelen Islands, part of the French Southern and Antarctic Lands, are an overseas territory of France. But their far-off location in the southern Indian Ocean places these islands far closer to Antarctica than to mainland Europe. In fact, the islands are so remote and the landscape so harsh that they have also been called the “Desolation Islands.”
Kerguelen is throughout mountainous, made up of a series of steep-sided valleys separated by ridges and mountain masses, which rise to very considerable heights. Mount Ross, the highest, is 6120 feet in altitude, Mount Richards 4000 feet, Mount Crozier 3250, Mount Wyville Thomson 3160, Mount Hooker 2600, and Mount Moseley 2400. The island thus, when viewed from the sea at a distance, presents a remarkable jagged outline of sharp peaks, which is most striking when observed from the south. The valleys run down everywhere to the sea, broadening out as they approach it. The whole coast is broken up by deep sounds or fjords, which resemble closely in form the fjords of Norway and other parts of the world. They are long channel-like excavations of the coast line, occupied by arms of the sea, often shallower at the mouths than nearer to the upper extremities, and bounded on either hand by perpendicular cliffs.
At the seaward termination of the southern promontory is the well~known arched rock of Christmas Harbour, a roughly rectangular oblong mass, evidently at some former period directly continuous with the rest of the promontory, but now separated from it, except at its very base, by a chasm, and perforated so ast-o form an arch. Above the high cliffs on the'south side of the harbour towers a huge and imposing mass of black~looking rock with perpendicular faces, named Mount Havergal; this overhangs somewhat towards the harbour from the weathering out of soft strata beneath it, and looks as if it might fall and fill the upper part of the harbor. On the north side rises a flat-topped rocky mass 1215 feet in height, called Table Mountain.
At the head of the harbor is a sandy beach and small stretch of flat land, such as exists at the heads of all the fjords, and beyond this the land rises in a series of steps, separated by short cliffs towards the bases of Table Mountain and Mount Havergal. The appearance of the whole is extremely grand, and the marked contrast between the blackness of the rocks and the bright yellow green of the rank vegetation clothing all the lower region of the land, so characteristic of all these so-called Antarctic Islands, renders the general effect in fine weather very beautiful.
The islands were discovered by the French navigator Yves-Joseph de Kerguelen in 1772. M. de Kerguelen, a lieutenant in the French service, had the command of two ships given him, the La Fortune, and Le Gros Ventre. He sailed from the Mauritius about the latter end of 1771. On 13 January 1772, M. de Kerguelen saw land, as it is said, of a considerable height and extent. The first land was sighted upon the 12th of February 1772. Next day a second was discovered, and shortly afterwards a very lofty and extensive cape. The following day at seven o'clock in the morning, the sun having dispelled the clouds, a line of coast extending some twenty-five leagues was clearly seen.
Kerguelen returned to France, but his successful enterprise had guined him many enemies. M. de Kerguelen was afterwards promoted to the command of a 64 gun ship, called the Roland, with the frigate L'Oiseau, were sent out in order to perfect the discovery of this pretended land. The Roland, and the frigate Oiseau, left Brest. On the 5th of January On the 5th of January, Kerguelen sighted the lands he had discovered in his first voyage, and between that date and the 16th he recognized various points, Kerguelen sighted the lands he had discovered in his first voyage, and between that date and the 16th he recognized various points. Once again, the prostrate condition of the crew, the bad quality of the victuals, and the dilapidated state of the vessels, prevented Kerguelen from making a thorough investigation of this desolate archipelago.
M M. de Roches and Poivre, who had contributed so essentially to the success of the first expedition, had been succeeded by M. do Ternay and the Intendant Maillard. They appeared determined to offer every possible obstacle to the execution of Kerguelen's orders. They gave him no fresh victuals, of which the crew had pressing need, and there were no means of replacing masts destroyed by tempest. In lieu of the thirty-four sailors who had to go to the hospital, he was provided only with disgraced or maimed soldiers, of whom he was glad to rid himself. An expedition to the southern seas, so equipped, could only come to a disastrous end; and that was precisely what happened. On his return to France, Kerguelen met with nothing but ill-will and calumny, in return for so much fatigue, so bravely born. The feeling against him was so strong that one of his officers was not ashamed to publish a memoir, in which all the facts were dressed up in the most unfavourable shape, and the failure of the enterprise thrown upon Kerguelen. The verdict of the council of war which deprived him of his rank, and condemned him to detention in the Chateau of Saumur, was most unjust. No doubt the judgment was found to be excessive, and the government discerned more malice than justice in it, for a few months later Kerguelen was restored to liberty.
Kerguelen was peculiarly unfortunate, in having done so little to complete what he had begun. He discovered a new land indeed; but, in two expeditions to it, he could not once bring his ships to an anchor upon any part of its coasts. Captain Cook had either fewer difficulties to struggle with, or was more successful in surmounting them, when he visited in 1776 [not 1779].
From its sterility, it might properly have been called the Island of Desolation: but Captain Cook was unwilling to rob M. Kerguelen of the honor of its bearing his name. Mr. Anderson, who accompanied Captain Cook in this voyage, said that no place hitherto discovered in either hemisphere afforded so scanty a field for the naturalist as this spot. Some verdure indeed appeared, when at a small distance from the shore, which might raise the expectation of meeting with a little herbage; but all this lively appearance was occasioned by one small plant, resembling saxifrage, which grew upon the hills in large spreading tufts, on a kind of rotton turf, which, if dried, might serve for fuel, and was the only thing seen here that could possibly be applied to that purpose.
Until the XXth century, the archipelago was regularly visited by whalers and sealers (mostly British, American and Norwegian) who hunted the resident populations of whales and seals. They introduced populations of rabbits, sheep and reindeer. The Kerguelen whale and seal fishery would appear to have dwindled very considerably since the time of Sir James Ross. At the time of the Challenger’s visit (1874) it employed a barque, two schooners, and a party of twenty-nine men on Heard Island. The barque and schooners belong to New London, Connecticut; the schooners remain at Kerguelen, whilst the barque (the “Roman ”) keeps up the communication with America, bringing out supplies and taking back the season’s oil and seal-skins. The “Roman” arrived at Kerguelen every year in September, and met the two schooners (“RosWell King" and “Emma Jane ”) at Island Harbour, Royal Sound.
They start for Heard Island, and remain in its vicinity until the Elephant Seal season is over — about the middle of December — after which they return to Kerguelen, when the “Roman” left for America, and the schooners hunt for whales until the end of June. The men engaged in the fishery were Americans and Portuguese, the latter from the island of Brava, one of the Cape Verde group. They sign articles for three years, and are relieved, so many annually, by new hands brought out in the “Roman.”
The desolate situation, almost three thousand miles away from any habitable spot; the dreary aspect of an island of rock and lake and bog, without man or beast or tree to break the monotony of its loneliness; and most of all, the fearful approach through mist and storm, with waves the greatest in the world, and winds blowing a gale five days out of every seven—all tended to create a sympathy for those who had the honor of being intrusted with this post.
Situated in the center of the Southern Ocean, and more remote than any other island from a continent, Kerguelen's Land, or the Island of Desolation, is about 100 miles in length and 60 in breadth, and seems to be chiefly composed of trap and other volcanic rocks, which rise into hills from 500 to 2500 feet high. The coast is deeply indented with bays and inlets, and the whole surface is intersected by lakes and watercourses. Owing to the coldness and moisture of the climate, the island is almost totally destitute of vegetation, and is generally spoken of by navigators as one of the bleakest and most desolate spots on the globe.
Grande Terre (French for “large land”) is the most sizeable in the island group. Its steep fjords and peninsulas are ringed by hundreds of smaller islands, which bring the archipelago’s total land area to 7215 square kilometers (2,786 square miles).
Penguin and seal populations are among the wildlife that thrive on Grande Terre. But because of its remoteness — and the severely cold, windy weather — there aren’t many people. Most residents of the island are scientists based in the settlement of Port-aux-Français, where they study everything from geology and biology to weather and climate.
Southern elephant seals (Mirounga Ieonina) have a circumpolar distribution and can be divided into three geographically and genetically isolated stocks in the Southern Ocean: the South Georgia stock in the Atlantic sector, the Macquarie stock in the Pacific sector and the Kerguelen stock in the Indian Ocean sector. They inhabit a variety of subantarctic islands around the Antarctic Convergence and forage widely in the Southern Ocean, feeding primarily on deep, benthic or pelagic prey, mostly squid. Although most of the populations in the southern Atlantic Ocean are increasing, all other populations endured dramatic declines between the 1940s and 1980s.
In 1990, the Iles Kerguelen stock represented about 28% of the total population of elephant seals, and had declined dramatically over the previous 40 years. The Iles Kerguelen stock comprises separate populations breeding at a number of subantarctic islands in the Indian sector of the Southern Ocean; specifically, Marion Island, Iles Crozet (Possession Island), Kerguelen Island and Heard Island.
One area of research involves the myriad bodies of ice. Researchers have shown that between 1963 and 2001, ice-covered areas of the Kerguelen Islands shrank by 21 percent — a phenomenon that’s in-line with what’s happening in Patagonia, South Georgia, and other sub-polar latitudes. Over the same span, the Cook Ice Cap shrank from 501 to 403 square kilometers. And the losses have continued: Subsequent research published in Nature noted that glacier wastage on the islands during the 2000s was “among the most dramatic on Earth.” The main reason was less precipitation and drier air.
But that just scratches the surface of the region’s interesting features. The islands are actually some of highest points on a huge underwater plateau. Given the right nutrients and physical conditions, spectacular blooms of phytoplankton can make an appearance in the waters over the plateau.
About 50 million years ago, Australia and Broken Ridge separated from East Antarctica and the Kerguelen Plateau, and since that time the Indian-Antarctic Ridge and Mid-Indian Ridge have been continuous. Sea-floor magnetic spreading anomalies suggest that Broken Ridge separated from the Kerguelen Plateau, and thus that if one is continental both are. Both the Kerguelen Plateau and Broken Ridge have thick covers of sediments going back at least to the early Late Cretaceous. DSDP drilling shows Broken Ridge to have been continuously at shallow depths since at least middle Late Cretaceous time, and for one interval to have been above sea level, which is highly suggestive of continental crust. Gravity and magnetic studies indicate the Naturaliste Plateau, on strike to the east of Broken Ridge, to be continental.
Of the two DSDP holes on the Naturaliste Plateau, one stopped in shallow-water Lower Cretaceous strata without reaching crystalline rocks, and the other penetrated andesitic to rhyolitic arc volcanic rocks beneath Upper Cretaceous chalk. Continental crystalline basement rocks were dredged from the plateau by Heezen and Tharp (1973). The very large Kerguelen Plateau has been near its present altitude throughout at least much of Cenozoic time, for middle Tertiary lignites contain fossil land plants. The Tertiary trees included podocarps and araucarians, which are the characteristic conifers in the wet-temperate forests of the southern hemisphere continents that were joined in Cretaceous time and which probably cannot cross oceanic gaps.
Alkalic basalts, trachytes, and their intrusive equivalents cover most of the Kerguelen islands, have potassium-argon ages of 1 to 30 m.y., and have compositions that could represent a purely oceanic island, but ratios of 87Sr/86Sr of 0.704 to 0.706 that make contamination by silicic crust likely. Gravity anomalies indicate the Kerguelen Plateau to be in approximate isostatic equilibrium and thus to have a thick crust. Seismic-refraction studies define the acoustic velocity, about 5 km/sec, of only the uppermost part of the crystalline crust beneath the strata capping the Kerguelen Plateau, and hence do not prove whether that crust is of oceanic or continental character.
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