Earthquakes.......

Earthquakes are sudden movements in the earth’s crust that cause tremor's or vibration's. They, like volcanoes, usually occur along the edges of the plate boundaries; these edges are called fault lines . When the plates collide or rub against one another this will cause and earthquake.Focus is the word used to describe the spot within the earth’s crust where the earthquake begins. The epicentre is the place on the earth’s surface directly above the focus. Shock waves are sent out from the epicentre and focus and they cause the major damage often associated with earthquakes. The nearer to the epicentre themore severe the damage.

A seismograph is the intrument used to record the earthquake and the scale used to measure the strength of an earthquake is called the Richter Scale. This scale ranges from 1-12 and each step.

Volcanos.....

Volcanoes happen when hot magma forces its way to the surface through a channel in the earth’s crust called a vent. These vents are usually found at plate boundaries or where the earth’s crust is very thin. When the hot molten rock reaches the surface it is known as lava . When lava is reaching the earth's surface, it is known as erruption. When these erruptions are reapeted around a vent, it eventually build's up to form a cone-shaped mountain. Volcanoes are classified as being active (erupting regularly), dormant (no eruption for a very long period) and extinct (when they have not erupted in recorded time and probably won't again). The ‘Pacific Ring of Fire' is a region where two thirds of the world's volcanoes are found.

Volcano Diagram:

1. Magma chamber

2. Bedrock

3. Conduit (pipe)

4. Base

5. Sill

6. Branch pipe

7. Layers of ash emitted by the volcano

8. Flank

9. Layers of lava emitted by the volcano

10. Throat

11. Parasitic cone

12. Lava flow

13. Vent

14. Crater

15. Ash cloud

NATURAL DISASTERS!

For my geography blog i have decided to write about all different kinds of natural disaters. These include avalanches, tornadoes, volcanoes, earthquakes, tsunamis, and floods. I'm writing about these because i find natural disasters very interesting and i hope to learn a lot more about them.