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This website is designed for Geography lovers everywhere and in particular to those studying Geography. I hope you enjoy the site.

Geography (from Greek γεωγραφία - geografia) is the study of the Earth and its lands, features, inhabitants, and phenomena. A literal translation would be "to describe or write about the Earth". The first person to use the word "geography" was Eratosthenes (276-194 B.C.). Four historical traditions in geographical research are the spatial analysis of natural and human phenomena (geography as a study of distribution), area studies (places and regions), study of man-land relationship, and research in earth sciences. Nonetheless, modern geography is an all-encompassing discipline that foremost seeks to understand the Earth and all of its human and natural complexities-- not merely where objects are, but how they have changed and come to be. As "the bridge between the human and physical sciences," geography is divided into two main branches - human geography and physical geography.

Sunday, February 8, 2009

Plate Tectonics

A theory that the Earth outer shell consists of a series of rigid plates known as the lithosphere. These plates move in response to convection currents within the mantle. The interactions of the plates at their boundaries yield earthquakes, volcanic activity, ocean trenches, island chains, mountain ranges and other features.

Tectonic plates are sections of the Earth's solid crust that “float” on top of the mantle.
The mantle contains hot molten rock (magma) heated by energy from the earth's core
The earth’s crust is made up of seven main tectonic plates and numerous smaller plates.

There are two main types of tectonic plate.
Oceanic plates are relatively thin (about 6-10 km) and contain very heavy (dense) rocks such as basalt.

Continental plates are considerably thicker (35-40 km) but contain lighter (less dense) rocks such as granite.
The plates fit together like pieces of a large jigsaw. Tectonic plates meet along four main types of plate boundaries.

The tectonic plates are in constant motion travelling at a few centimetres per year.
The ocean floors are continually moving, spreading from the centre and sinking at the edges.
Where plates meet, huge forces build up causing earthquakes and volcanoes and the formation of fold mountains and deep-sea trenches.

Have a look at the different plate boundaries in the world and what type of features they create:

The video below shows how the continents have drifted apart over millions of years. This theory is known as Continental Drift.

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