The Earth is covered by water, which occupies 71 percent, and land, which occupies 29 percent of the Earth's surface. The surface is not even, because it has lofty mountains, deep oceans and other landforms. Landforms are classified as first order, second order and third order landforms.
1. Pangea and Panthalasa
- Pangea was the Super Continent, and the sea around it was Panthalasa.
- It was 200 million years ago that these landmasses moved away from each other to gain their present position as continents and oceans.
- What made them move was the internal heat of the Earth.
2. Classification of Landforms
| Order | Landforms | How they are described |
|---|---|---|
| First order | Continents and oceans | Vast land masses (continents) and huge water bodies (oceans) |
| Second order | Mountains, plateaus and plains | Found on the continents |
| Third order | Valleys, beaches and sand dunes | Formed on mountains, plateaus and plains mainly by erosional and depositional activities of rivers, glaciers, winds and waves |