Geology / Earthquakes
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| Earthquake data is not available for this date (at present) |
Data kindly supplied by : U.S. Geological Survey
Notes
1. The time of the earthquake is given in Greenwich Mean Time (GMT) or now known as Universal Co-ordinated Time (UCT). You may need to take into account of local time zone.
2. The magnitude of the earthquake is not a linear scale. Each unit represents that the earthquake is ten times greater - it is a logarithmic scale. This is the most important thing to bear in mind. The difference between magnitude 3.0 and 6.0 is a thousand times, and 9.0 is a million times stronger than 3.0.
| Magnitude | Effects | Occurrences each year |
| less than 2.5 | Not usually felt, detected only by sensitive seismographs | millions |
| 2.5 to 5.4 | Often felt, objects may shake, but only causes minor damage | 40,000 |
| 5.5 to 6.0 | Limited localised damage to buildings close to epicentre | 800 |
| 6.1 to 6.9 | May cause considerable damage in heavily populated areas | 150 |
| 7.0 to 7.9 | A Major earthquake with potentially serious damage | 15 |
| over 8.0 | Devastating at epicentre, felt thousands of miles away | 1 |
3. The epicentre of an earthquake is located vertically above the source. The depth of the earthquake will determine how significant the effects of the quake, shallow ones are normally more destructive.
4. In areas where earthquakes are frequent the infrastructure is designed to cope with all but the very strongest earthquakes. A large earthquake in an area where they rarely occur would have a much greater effect.
5. The size of circle denoting the earthquake is proportional to its magnitude.
6. The color of the circles represents the time in GMT of the quake. Blue ones are early in the day and the circles become progressively redder as the day wears on.