Geology / Earthquakes
Earthquakes are the most widely spread evidence that the Earth is still active. It has been active since it was first formed billions of years ago. Just one billion years ago the Earth had somewhat settled down, there were areas of land (continental crust) surrounded by oceans with their thinner, denser oceanic crust deep beneath the waves. The earth's surface became divided into stable areas of crust with mobile unstable margins. As the oceanic crust cooled it became denser and fell back into the semi-liquid (on a geological time scale) vast volume of the Earth's mantle. This thick mantle is itself driven by convection currents that are continually transporting heat energy from the still hot Core to the cold crust.
One of the main causes of earthquakes are the jerky but remoreseful movements of the plates as they slide, crush or descend past each other. These events cause the really big earthquakes. Alternatively the ascent of the hot magma from the mantle can cause earthquakes, but these tend to be not as strong and not as deep. An eruption of a large volcano can cause local earthquakes as the magma rises and stresses the shallow rocks. Human activity can create small earthquakes too, this often happens when a rivers are dammed and the huge weight of the water building up in the lake causes stresses in the underlying rocks.
This site has an archive of earthquakes in recent times both as a list of events and as an animation. Looking at the pattern of earthquakes over the last few months quickly demonstrates the location of the active plate margins around the world.
If you'd like to look at recent earthquakes, we have generated some pages using data supplied by :
U.S. Geological Survey
| Date and Time | Strength, Location | Latitude | Longtitude |
| July 28, 2010 22:51:35 GMT | M 5.1, Rota region, Northern Mariana Islands | 14.8916 | 146.9575 |
| July 28, 2010 22:37:01 GMT | M 3.3, Northern California | 38.8162 | -122.7917 |
| July 28, 2010 20:20:16 GMT | M 4.1, Andreanof Islands, Aleutian Islands, Alaska | 52.6895 | -172.1530 |
| July 28, 2010 20:03:50 GMT | M 2.7, Southern Alaska | 59.9463 | -153.1791 |
| July 28, 2010 19:49:25 GMT | M 3.9, Fox Islands, Aleutian Islands, Alaska | 52.7065 | -169.5297 |
| July 28, 2010 18:21:15 GMT | M 5.3, Santa Cruz Islands | -12.2519 | 165.4551 |
| July 28, 2010 16:58:56 GMT | M 4.1, Fox Islands, Aleutian Islands, Alaska | 52.7898 | -169.3824 |
| July 28, 2010 16:12:05 GMT | M 5.2, off the coast of Oregon | 43.7568 | -125.7982 |
| July 28, 2010 14:28:37 GMT | M 3.0, Baja California, Mexico | 32.1693 | -115.2475 |
| July 28, 2010 13:32:12 GMT | M 4.1, Fox Islands, Aleutian Islands, Alaska | 52.6375 | -169.3359 |
| July 28, 2010 12:35:21 GMT | M 4.1, Fox Islands, Aleutian Islands, Alaska | 52.7407 | -169.1982 |
| July 28, 2010 12:22:25 GMT | M 4.5, south of Panama | 4.7723 | -82.5467 |
| July 28, 2010 12:07:47 GMT | M 5.0, Fox Islands, Aleutian Islands, Alaska | 52.7657 | -169.3983 |
| July 28, 2010 12:07:11 GMT | M 2.6, Fox Islands, Aleutian Islands, Alaska | 52.5980 | -169.0277 |
| July 28, 2010 11:44:39 GMT | M 2.8, Baja California, Mexico | 32.0315 | -115.2153 |
| July 28, 2010 11:37:46 GMT | M 4.0, Fox Islands, Aleutian Islands, Alaska | 52.6457 | -169.3506 |
| July 28, 2010 11:37:34 GMT | M 2.6, Northern California | 38.3793 | -121.5147 |
| July 28, 2010 11:31:50 GMT | M 5.5, Fox Islands, Aleutian Islands, Alaska | 52.6833 | -169.3087 |
| July 28, 2010 11:30:29 GMT | M 4.6, Fox Islands, Aleutian Islands, Alaska | 52.7524 | -169.3781 |
| July 28, 2010 11:15:28 GMT | M 2.5, Baja California, Mexico | 32.5407 | -115.7315 |
| July 28, 2010 10:09:25 GMT | M 4.8, Kepulauan Mentawai region, Indonesia | -3.0457 | 100.8069 |
| July 28, 2010 08:07:09 GMT | M 4.8, Mindanao, Philippines | 6.9611 | 126.6253 |
| July 28, 2010 07:22:35 GMT | M 3.0, Baja California, Mexico | 32.0638 | -115.2315 |
| July 28, 2010 07:21:58 GMT | M 3.4, Baja California, Mexico | 32.0750 | -115.2065 |
| July 28, 2010 04:07:54 GMT | M 4.4, Fox Islands, Aleutian Islands, Alaska | 52.6854 | -169.5368 |
| July 28, 2010 02:39:31 GMT | M 2.8, offshore Northern California | 40.5603 | -124.7305 |
| July 28, 2010 02:36:04 GMT | M 2.6, Central California | 37.4128 | -118.6012 |
| July 28, 2010 01:44:52 GMT | M 2.7, Andreanof Islands, Aleutian Islands, Alaska | 53.5330 | -174.4262 |