About a billion years after the earth had formed, the first signs of life appeared. Three billion years elapsed before creatures became complex enough to leave fossils their descendants could recognize and learn from. These were shelled creatures called trilobites, followed by jawless fish, the first vertebrates. During the Devonian period, great upheavals occurred in the earth’s crust, resulting in the formation of mountains and in the ebb and flow of oceans. In the aftermath, beds of mud rich in organic matter nourished vegetation, and insects, scorpions, and spiders appeared. Next developed the amphibians, descendants of fish that had crawled out of fresh water.

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“Oil has become the ‘new gold’ – a financial asset in which investors seek refuge as inflation rises and the dollar weakens,” said Daniel Yergin, chairman of CERA and executive vice president of IHS. “The credit crisis has been fueling the flight to oil and other commodities, and that will last until the dollar strengthens or the recession becomes more pronounced.”

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Earthquakes are the most lethal of all natural disasters. What causes them? Geologists explain them in terms of a theory known as plate tectonics. Continents are floating apart from each other; this is referred to as the continental drift. About sixty miles below the surface of the sea, there is a semimolten bed of rock over which plates, or slabs, carry continents and sea floors at a rate of several inches a year. As the plates separate from each other, a new sea floor is formed by the molten matter that was formerly beneath. Volcanic islands and large mountain ranges are created by this type of movement. The collision of plates causes geological instability such as that in California called the San Andreas Fault, located between the Pacific and North American plates. The plates there are constantly pushing and pulling adjacent plates, thereby creating constant tremors and a potential for earthquakes in the area.

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