Krakatoa is located in Indonesia, between the islands of Java and Sumatra, in the Sundra Straits. It is surrounded by over 130 other volcanoes that lie along the Indonesian Island Arc.


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Before 1883:

Krakatoa island once contained three volcanoes called Perboewetan, Danan and Rakata.


(This image can be found at http://www.earlham.edu/~bubbmi/krakatoa.htm, along with additional information on the Krakatoa Island before it errupted in 1883.)

After the explosion in 1883:

On 17th of August, in the year 1883, the massive Krakatoa Volcano erupted. The massive eruption caused various parts of the island, once called Rakata, to collapse, and the middle of the island to ascend. It is currently one island called Krakatoa with three islands close to it called Land, Verlaten and Anka Krakatoa, as shown in this image.

(This diagram, displaying the current layout of Krakatoa Island, can be found at http://www.earlham.edu/~bubbmi/krakatoa.htm)

How did Krakatoa Occur:

Krakatoa was formed by the subduction process. This process occurs when two tectonic plates collide, causing one plate, generally the more dense, to subduct under the other. In this case, the European plate was pushed beneath the Indonesian-Australian plate. Throughout this process, friction is caused by the movement of the plates and heat is developed. The heat then increases the temperature and pressure of the mantle, causing it to rise and explode out of the volcano’s crater with intense speed and power. The sound of Krakatoa’s explosion was massive, as it was heard 4500 kilometres away from its destination. The ash and gases formed from the volcano was approximately 11 kilometres above the summit. This volcano's horrific impacts harmed many countries all over the world.