This week in year 4...

These mountains are the most common type of mountain. These ranges were formed over millions of years. These mountains are formed when two plates collide head on, and their edges crumbled, much the same way as a piece of paper folds when pushed together.

These mountains form when faults or cracks in the earth's crust force some materials or blocks of rock up and others down. Instead of the earth folding over, the earth's crust fractures (pulls apart). It breaks up into blocks or chunks. Sometimes these blocks of rock move up and down, as they move apart and blocks of rock end up being stacked on one another.

These mountains are the result of a large amount of melted rock(magma) pushing its way up under the earth crust. Without actually erupting onto the surface, the magma pushes up overlaying rock layers. At some point, the magma cools and forms hardened rock. The uplifted area created by rising magma is called a dome because of looking like the top half of a sphere. The rock layers over the hardened magma are warped upward to form a dome like surface.

We have been learning all about the different types of mountains. There are 5 main different types of mountains:-

1.Fold Mountains

2.Fault-Block Mountains

3.Dome Mountains

4.Volcanic Mountains

5.Plateau Mountains

These kind of Mountains are formed when molten rock (magma) deep within the earth, erupts, and piles upon the surface. Magna is called lava when it breaks through the earth's crust. When the ash and lava cools, it builds a cone of rock. Rock and lava pile up, layer on top of layer.

These type of mountains are formed by erosion. As the years pass, streams and rivers erode valleys through the mountains, leaving them standing between the valleys.They have large flat areas that have been pushed above sea level by forces within the Earth, or have been formed by layers of lava. The mountains in New Zealand are good examples of this type of mountain.

Can you work out which one is which?