Geography and geology

Introduction

For thousands of years scientists from different countries have been contributing important discoveries and ideas that shaped a modern science. This chapter looks at some important discoveries in the field of geography and geology.

Where did it all begin?

Geography is the study of the Earth's surface, its features, climate and population. Geology is the study of the Earth's structure and its chemical composition. Geology and geography are closely connected.

The foundations of geography can be traced back to prehistoric times. The first 'geographical map' was probably drawn in the sand with a stick by a prehistoric man, who tried to explain to his friend how to get to the forest where he could find the best mushrooms and berries.

Much later, the Ancient Greeks drew the first recorded geographical maps. In those days people still believed that the Earth was a flat disk. People did not travel long distances as durable transport had not yet been invented, therefore they had a limited knowledge of places beyond their immediate environment.

Eratosthenes, a third century BC chief librarian at the famous Library of Alexandria (a city in Egypt), was the first person to use the word geography and to calculate the circumference of the Earth. The Ancient Greek scientist Hipparchus developed the system of latitude and longitude lines. Latitude lines are imaginary lines that cross the surface of the Earth parallel to the equator. Longitude lines are imaginary lines that cross the surface of the Earth, running from north to south. The Ancient Greek scientist Ptolemy was the first to draw detailed atlases. 

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An eleventh century scientist from China, Shen Kua, came up with the idea that land forms were created by erosion (the wearing away of the surface of the land by wind, water and ice) and by soil and sand deposits. A seventeenth century scientist, Nicolaus Steno, came up with the statement that the deepest rocks are the oldest. This statement now is referred to as the law of superposition.

The sixteenth and seventeenth centuries are often referred to as The Age of Discovery. During this time, European ships were travelling around the world looking for new, more efficient, trading routes. In the process, they mapped many lands which were previously unknown to them.

Christopher Columbus was a fifteenth century explorer who discovered America. Vasco da Gama was a Portuguese explorer was the first person to sail directly from Europe to India. Ferdinand Magellan was another Portuguese explorer who became the first person to lead an expedition sailing from Europe to Asia and crossed the Pacific Ocean. Captain James Cook was an English explorer and cartographer (a person who makes maps). Cook made three trips to the Pacific Ocean, reaching the eastern coastline of Australia. He also was the first European to discover the Hawaiian Islands and mapped Newfoundland (an island in the north Atlantic) and New Zealand.

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An eighteenth century scientist, William Smith, drew some of the first geological maps and began the process of organising rock strata (layers) by examining the fossils contained in them. Sir Charles Lyell first came up with the theory stating that slow geological processes have been happening since the formation of our planet. During the eighteenth and nineteenth centuries, geography became a compulsory subject at many European universities.

The theory of plate tectonics was first formulated by the scientist Alfred Wegener at the beginning of the twentieth century, however it did not become widelu accepted until the 1960s. According to this theory, the Earth's crust is divided into approximately 28 large, slowly moving plates, called tectonic plates. The movement of these tectonic plates is called plate tectonics. All continents, oceans and islands sit on tectonic plates.

Today, geography and geology are divided into many different branches that specialise in different fields of research. Computers, computer programs and aerial photography (pictures taken from an aircraft or satellite) help people to study and better understand our environment.

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