All of the earthquakes recorded around the world in 2016.
When covering plate tectonics, using this layer is a good place to start – even before any ideas of plate tectonics are covered. I will let my students look around the Earth for a while to take note of any patterns that they can discern. Some of things I try to get my students to recognize include:
- The overall distribution of earthquakes across the world are not random or even. Earthquakes are usually clustered into narrow bands [usually denoting plate boundaries]. Some of these boundaries are along the coasts of continents and sometimes they are in the middle of the ocean.
- Earthquakes are not all the same depth – shallow earthquakes are far more common. [usually associated with rifting]
- Shallow earthquakes are often associated with elongate bodies of water. [rift zones such as East Africa rift, the Red Sea]
- When earthquakes vary in depth, there is a pattern that emerges – the shallow earthquakes become deeper in one direction. [caused by the subduction of one plate beneath the other]
- The earthquakes in the middle ocean correlate with patterns in ocean topography (shown in Google Earth). [spreading center / mid oceanic rift]
- Shallow earthquakes are often associated with elongate bodies of water. [rift zones such as East Africa rift, the Red Sea]
- Complex patterns of earthquakes where India meets the rest of Asia. [continental collision, creating Himalayan mountains]
KML file for Google Earth: EQs_2016_4+
Example JPG showing earthquakes in Central America: world earthquakes 1