ESL Blogs

Yesterday, on Friday March,11th 2011, there was big earthquake happened twice in Japan for about 8.8 and 7.9 ritcher scale, far stronger than the one that devastated Christchurch, New Zealand. And even made a powerful tsunami swept across the large area of North Japan. About more than 300 people died and more than 500 people are missing . Let us pray for them..

So what is earthquake? Why it can be happened and what's it caused by?

As you know,our earth is very complex. Our earth is consists of core (including inner core and outer core), mantle, and crust. Crust is divided into many plates that moving each other. There are two kind of plate, continental plate and ocean plate.. You can look at below picture to see the dividing.

So when one plate that has more density was subducted or moving below another plate, and it has reached it's critical elasticity, it will fracture. The fracture will make earthquake. Like what happened in Japan, Pasific plate moving to west and has subducted below Eurasian plate,finally fracture and made a big earthquake. You can notice the areas in the edges of every plates, they are active tectonic areas, sign by a lot of volcanoes there and so often earthquake happened. It also called as "ring of fire", in the picture above is marked by a lot of red dots. 

My beloved country, Indonesia, also included in "ring of fire", because it's located in the meeting of three plates, Eurasian plate, Indo-Australia plate, and Pasific plate (it's called as "triple junction"). So I can say that earthquake is happened in around of Indonesia everyday. And it also has a lot of active volcanoes because of the subduction.