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The Earth

Increasingly, the earth science has become more closely related to people’s daily lives. From topics of little more than academic interest, they have developed to provide information of fundamental importance to many human activities  – from agriculture to weather forecasting. Perhaps more important, increasing knowledge has led to a better understanding of the complex interactions between the various earth processes and between human beings and their planet. In particular we have come to realize that, a part from the sun’s radiation all of our fuels and material resources are products of the earth and are, therefore, almost all finite.

The discovery and exploration of natural resources is perhaps the strongest driving force in our attempt to understand the earth. But it is not all. Natural curiosity, which everyone has to some degree, is aroused whenever we look around and contemplate our natural environment and it reflects the inquiring minds of eighteens century geologists.

What makes hills and mountains? When were they formed? Why is our climate so different from that of the Sahara, and has it always been like this? Specu­lation on questions like these stretches back at least as far as the ancient Greeks, long before modern scientific study.

It must be remembered that at the time Columbus’ crew set sail for India in the early 1490’s, many people believed the sheep would sail “over the edge”. Nearly four centuries later, however, little was known about the earth’s composition and geological history. Toward the end of the eighteenth century, Abraham Gottlob Verner, a German geologist, formulated the theory on the origin of the earth that was widely accepted at his time. According to his theory the earth was created with primitive rocks and a primeval ocean.

Through the first half of the nineteenth century his followers (the Neptunists) were opposed by supporters of James Hutton. According to Hutton, the earth’s history consisted of repeated episodes of rock formation followed by periods of destruction or erosion. The same theme was taken up in the mid-nineteenth century by Charles Darwin and his supporters. Lord Kalvin estimated its age to be between twenty and forty million years. Hutton’s theory provided
a paradigm as fundamental to the earth sciences as Newton’s contributions to physics.