Cycles of death

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An event of the brevity and magnitude of a great basalt flood is an obvious shock to the surface world. “We don’t know what flood basalts do to the atmosphere,” Morgan remarked one day in i985, showing me a chronology he had been making of the great flood basalts that not only filled every valley “like water” and killed every creature in areas as large as a million square kilometres but also may have spread around the world lethal effects through the sky. Morgan’s time chart of flood basalts matched almost exactly the cycles of death tlrnt are currently prominent in the dialogue of massextinction theorists, including the flood basalts of the Deccan Plateau, which are contemporaneous with the death of the dinosaursthe event that is zakelijke energie known as the Cretaceous Extinction. The perforations made by hot spots may be analogous to the perforations in sheets of postage stamps. Plume tracks might weaken the plates through which they pass, so that tens of millions of years later the plates would break apart along those lines. Madeira, for example, first drew the line where Greenland broke away from Canada. The Kerguelen Hot Spot, in the Indian Ocean, may have helped India break away from Antarctica. The Crozet Hot Spot, also in the Indian Ocean, seems to have helped Madagascar get away from Africa. In the interior of the southern supercontinent of three hundred million years ago, a hot spot punched out the line that is now the north coast of Brazil. The same line is the Gold Coast and Ivory Coast of Africa. The hot spot now stands in the Atlantic as the island St. Helena. The oldest rocks in Iceland are at the eastern and western extremes of the island, because Iceland is a hot spot whose track comes down from the northwest and at present intersects the zakelijke energie vergelijken Mid-Atlantic Ridge where Europe and America diverge. Iceland, for the time being, is spreading with the Atlantic. A hundred million years ago, the Mt. Etna Hot Spot was under the Ukraine, and seems to have cleaned off the Ukrainian Shield. A hot spot has made Ascension Island, on the South American Plate beside the Mid-Atlantic Ridge, fourteen hundred miles east of Brazil. It spent a hundred and ten million years under Africa after starting off from the Bahamas in early Jurassic time, when the transatlantic crossing was instantaneous, because there was no Atlantic.

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