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.R.T.Chamberlin says: "Some of these hugeice sheets advanced even into the tropics, where their deposits of glacier-borne debris,hundreds of feet in thickness, amaze the geologists who see them.No satisfactory explanationhas yet been offered for the extent and location of these extraordinary glaciers.Glaciers,almost unbelievable because of their location and size, certainly did not form in deserts." ®GreGnlsndGreenland is the contemporary example of what, according to the Ice Age theory, happened to alarge part of the world in times past.Greenland belongs to the great archipelago that crownsnortheastern Canada, though it is sometimes regarded as a part of Europe.It is the largestisland in the world, if we consider Antarctica and Australia as continents.Xhe island is 1660miles long, largely within the Arctic Circle, reaching the northern latitude of 83°39/.Of its840,000 square miles of surface, over 700,000 are covered with an immense mountain of icethat leaves free only the coastal fringes.Xhe thickness of the ice is measured by listening to theecho that comes from the bedrock when a detonation is set off on top of the ice.It is found to beover six thousand feet thick."For a long time it was the belief of many that a large region in the interior of Greenland was freefrom ice, and was perhaps inhabited.It was in part to solve this problem that Baron [N.A.E.]Nordenskjold set out upon his expedition of 1883." 1 He ascended the icecap from Disko Bay(latitude 69°) and went eastward for eighteen days across the ice field."Rivers were flowing inchannels upon the surface like those cut on land.only that the pure blue of the ice-walls was,by comparison, infinitely more beautiful.Xhese rivers were not, however, perfectly continuous.After flowing for a distance in channels on the surface, they, one and all, plunged with deafeningroar into some yawning crevasse, to find their way to the sea through sub-glacial channels.Numerous lakes with shores of ice were also encountered."1 Wright, The Ice Age in North America, p.75."On bending down the ear to the ice," wrote the explorer, "we could hear on every side apeculiar subterranean hum, proceeding from rivers flowing within the ice; and occasionally aloud single report like that of a cannon gave notice of the formation of a new glacier-cleft.Inthe afternoon we saw at some distance from us a well-defined pillar of mist which, when weapproached it, appeared to rise from a bottomless abyss, into which a mighty glacier-river fell.The vast roaring water-mass had bored for itself a vertical hole, probably down to the rock,certainly more than 2000 feet beneath, on which the glacier rested." aThe Ice Age survived in Greenland.This arctic island reveals how vast continental areas lookedin the past.However, it does not explain how ice could have covered British Guiana orMadagascar in the tropics.And what is no less surprising, the northern part of Greenland,according to the concerted opinion of glaciologists, was never glaciated."Probably, then as now,an exception was the northernmost part of Greenland; for it seems a rule that the most northerlylands are not, and never were, glaciated, writes the polar explorer Vilhjalmur Stefans-son.3 "Theislands of the Arctic Archipelago," writes another scientist, "were never glaciated.Neither wasthe interior of Alaska." * "It is a remarkable fact that no ice mass covered the low lands ofnorthern Siberia any more than those of Alaska," wrote James D.Dana, the leading Americangeologist of the last century.5 In northern Siberia and on polar islands in the Arctic Ocean spiresof rock were observed that would certainly have been broken off if an ice cover had moved overthose parts.6Bones of Greenland reindeer have been found in southern New Jersey and southern France,and bones of Lapland reindeer in the Crimea.This was explained as due to the invasion of iceand the retreat of northern animals to the south.The hippopotamus was found in France andEngland and the lion in Alaska.To explain similar occurrences, an interglacial period wasintroduced into the scheme: the land was warmed up and the southern animals visited northernlatitudes.And since the change from one fauna to another took place repeatedly, four glacialperiods with three interglacial were generally counted, though the number of periods is notconsistent with all lands or with all investigators.2 Ibid.8 V.Stefansson, Greenland (1942), p.4.4R.F.Griggs, Science, XCV (1942), 2473.5 Dana, Manual of Geology (4th ed.), p.977.6 Whitley, Journal of the Philosophical Society of Great Britain, XII, 55.But why the polar lands were not glaciated during the[ce Age was never explained.Greenland presents still another enigma in the precedingformations, those of the Tertiary Age.In the 1860s, O.Heer of Zurich published his classicalwork on the fossil plants of the Arctic; he identified the plant remains of the northern parts ofGreenland as magnolia and fig trees, among other species.7 Forests of exotic trees and grovesof juicy subtropical plants grew in the land that lies deep in the cold Arctic and is immersedyearly in a continuous polar night of six months' duration.Cordis of the Polar ReyionsSpitsbergen in the Arctic Ocean is as far north from Oslo in Norway as Oslo is from Naples.Heer identified 136 species of fossil plants from Spitsbergen (78°56' north latitude), which heascribed to the Tertiary Age.Among the plants were pines, firs, spruces, and cypresses, alsoelms, hazels, and water lilies.At the northernmost tip of Spitsbergen Archipelago, a bed of black and lustrous coal twenty-fiveto thirty feet thick was found; it is covered with black shale and sandstone incrusted withfossilized land plants."When we remember that this vegetation grew luxuriantly within 8° 15' ofthe North Pole, in a region which is in darkness for half of the year and is now almostcontinuously buried under snow and ice, we can realize the difficulty of the problem in thedistribution of climate which these facts present to the geologist.1T O.Heer, Flora Arctlca Fossllis: Die fossile Flora der Polarlander (1868).l Archibaid Gcikie, Text-Book of Geology (1882), p.869.There must have been great forests on Spitsbergen to produce a bed of coal thirty feet thick.And even if Spitsbergen, almost one thousand miles inside the Arctic Circle, for some unknownreason had the warm climate of the French Riviera on the Mediterranean, still these thick forestscould not have grown there, because the place is six months in continuous night.The rest of theyear the sun stands low over the horizon.Not only fossil trees and coal but corals, too, were found there.Corals grow only in tropical water.In the Mediterranean, in the climate of Egypt or Morocco, it is too cold for them.But they grew inSpitsbergen.Today large formations of coral covered with snow can be seen [ Pobierz caÅ‚ość w formacie PDF ]