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[...]... down the middle ofthe Atlantic Ocean, bisecting Iceland, and separating the Eurasian and African plates in the east from the North and South American plates in the west Here too there are both volcanoes and earthquakes, but the former tend to involve relatively mild eruptions and the latter are small Driven by the mantle convection currents beneath, the plateswaltz endlessly across the surface of the. .. granite rock, as with the Indian Ocean and Eurasian plates, then the result of collision is the growth ofa high mountain range-in this case the Himalayas-and at the same time the generation of major quakes such as thatwhich Page 10 A VERY S H O R T INTRODUCTION T O T H E EARTH obliterated the Indian city of Bhuj in January 2001 O n the other hand, if a n oceanic plate made of dense basalt hits a low-density... has changed today, except perhaps the frequency of global catastrophes, and many on the planet still face a daily threat to life, limb, and livelihood from volcano, quake, flood, and storm The natural perils that have battered our race in the past, and which constitute a growing future threat, have roots that extend back over 4 billion years to the creation ofthe solar system and the formation of the. .. gigantic waves caused by a collapsing Hawaiian volcano mercilessly pounded the entire coastline ofthe Pacific Ocean Barely a thousand years before the birth of Christ, and again during the Dark Ages, much of eastern Europe and the Middle East was battered by an earthquake storm that levelled once great cities over an enormous area There is n o question that such tectonic catastrophes will strike again... Talk to the citizens of Mammoth in California about the threat of their local volcano exploding into life, or to the inhabitants of Memphis, Tennessee, about prospects for their city being levelled by a major quake, and they are likely to shrug and point out that they have far more immediate things to worry about The only explanation is that these people are in denial They are quite aware that Page 3 A. .. old the Earth is, if only to appreciate the notion that just because we have not experienced a particular natural catastrophe before does not mean it has never happened, nor that it will not happen again The Earth has been around just about long enough to ensure that anything nature can conjure u p it already has To give a true impression ofthe great age of our planet compared to that of our race,... perhaps I can fall back on an analogy I have used before Imagine the entirety of Earth's history represented by a team of runners tackling the three and a half laps ofthe 1,500 metres For the first lap our planet would be a barren wasteland of impacting asteroids and exploding volcanoes During the next the planet would begin to cool, allowing the oceans to develop and the simplest life forms to appear... of recent natural disasters Apocalypse, Cassell, 1999 2 The lithosphere Apocalyse, Cassell, 1999 3 A tornado National Oceanic and Atmospheric Administration/ Department of Commerce, Washington 4 Collapsed building, Gujarat quake Peter MacDiarmid/Rex Features 2001 5 Aftermath of the 1998 Sissano tsunami (Papua New Guinea) Brian Cassey/AP Photo 6 Ruins of St Pierre (Martinique) after 1902 eruption Mary... geologically The relative movements ofthe plates themselves, which comprise the crust and the uppermost rigid part ofthe mantle (together known as the lithosphere), are in turn directly related to the principal geological hazards earthquakes and volcanoes, which are concentrated primarily along plate margins Here a number of interactions are possible Two plates may scrape jerkily past one another, accumulating... however, make it dangerous For example, the spectacular volcanoes that in the early history of our planet helped to generate the atmosphere and the oceans have in the last three centuries wiped out a quarter ofa million people and injured countless others At the same time, the rains that feed our rivers and provide us with the potable water that we need to survive have devastated huge tracts ofthe planet . more logical for us to speculate that the human race's great adventure is about to end, rather than persist far into the future and across the vastness of galactic space. Somewhat worryingly,.