How Bad 8.9 Magnitude Earthquake that occurred in Japan

8.9 Richter scale earthquake which occurred in Japan have caused a tsunami and wipe out residents housing who live near the beach.

Maybe we want to know what impact the damage that can be generated by an earthquake as powerful as this.

Richter magnitudes
Description
Earthquake effects
Frequency of occurrence

Less than 2.0
Micro
Micro earthquakes, not felt.
About 8,000 per day

2.0–2.9
Minor
Generally not felt, but recorded.
About 1,000 per day

3.0–3.9
Often felt, but rarely causes damage.
49,000 per year (est.)

4.0–4.9
Light
Noticeable shaking of indoor items, rattling noises. Significant damage unlikely.
6,200 per year (est.)

5.0–5.9
Moderate
Can cause major damage to poorly constructed buildings over small regions. At most slight damage to well-designed buildings.
800 per year

6.0–6.9
Strong
Can be destructive in areas up to about 160 kilometres (100 mi) across in populated areas.
120 per year

7.0–7.9
Major
Can cause serious damage over larger areas.
18 per year

8.0–8.9
Great
Can cause serious damage in areas several hundred miles across.
1 per year

9.0–9.9
Devastating in areas several thousand miles across.
1 per 20 years

10.0+
Epic
Never recorded; see below for equivalent seismic energy yield.
Extremely rare (Unknown)

You can see more detail on wikipedia, here is the link http://en.wikipedia.org/wiki/Richter_magnitude_scale

Another reference about earthquake magnitude scale

Earthquake Magnitude Scale

Magnitude
Earthquake Effects
Estimated Number
Each Year

2.5 or less
Usually not felt, but can be recorded by seismograph.
900,000

2.5 to 5.4
Often felt, but only causes minor damage.
30,000

5.5 to 6.0
Slight damage to buildings and other structures.
500

6.1 to 6.9
May cause a lot of damage in very populated areas.
100

7.0 to 7.9
Major earthquake. Serious damage.
20

8.0 or greater
Great earthquake. Can totally destroy communities near the epicenter.
One every 5 to 10 years

Earthquake Magnitude Classes

Earthquakes are also classified in categories ranging from minor to great, depending on their magnitude.

Class
Magnitude

Great
8 or more

Major
7 - 7.9

Strong
6 - 6.9

Moderate
5 - 5.9

Light
4 - 4.9

Minor
3 -3.9

more detail visit this link http://www.geo.mtu.edu/UPSeis/magnitude.html

That picture above can show, how bad the damage caused by the quake 8.9 on the Richter scale and was followed by a 4-meter-high tsunami waves that occurred in Japan 11 March 2011.

I can imagine how big the impact of the damage caused by tsunami waves as high as 60 feet that occurred in Aceh in December 2004.

Note: you can see more picture about 2011 Japan Earthquake on http://www.ndtv.com/album/detail/japan-earthquake-triggers-tsunami-9342/