Surface of the Earth

Underneath the water that fills the oceans, and the dirt and plants that cover the land, the Earth’s surface layer is made of rock. Long ago, this rocky outer layer of Earth formed a hard crust when lava cooled.

The surface layer is broken into many large plates that move very slowly, much too slowly to see with your eyes. Mountain ranges are pushed up if two plates crash into each other. Other surface features are the result of the moving plates too, including the shape of the continents. About 250 million years ago, most of the land was connected together, and over time it has separated into seven continents as the plates move.

Most of the Earth's surface (70%) is covered with water, and the remaining 30% is taken up by the seven continental landmasses. However, underneath the water that fills the oceans, and the dirt and plants that cover the continents, the Earth’s surface layer is made of rock. This outer layer formed a hard, rocky crust as lava at the surface cooled 4.5 billion years ago.

The crust is broken into many large plates that move slowly relative to each other. Mountain ranges form when two plates collide and their edges are forced up. In addition, many other surface features are the result of the moving plates. The plates move about one inch per year, so millions of years ago the continents and the oceans were in different positions. About 250 million years ago, most of the land was connected together, and over time has separated into seven continents.

Most of the Earth's surface (70%) is covered with water, and the remaining 30% is taken up by the seven continental landmasses. However, underneath the water that fills the oceans, and the dirt and plants that cover the continents, the Earth’s surface layer is made of rock. This outer layer formed a hard, rocky crust as lava at the surface cooled 4.5 billion years ago.

The crust is broken into many large plates that move slowly relative to each other. Mountain ranges form when two plates collide and their edges are forced up. In addition, many other surface features are the result of the moving plates. The plates move about one inch per year, so millions of years ago the continents and the oceans were in different positions. About 250 million years ago, most of the land was connected together, and over time has separated into seven continents.