Earthquakes

Another consequence of plate collisions is earthquakes!  As plates move, they don't do so smoothly. Instead, the two blocks of rock are locked together until enough force builds up to overcome the friction in a sudden shift.  It is this sudden movement that causes an earthquake.  Almost anyone who has lived in Alaska very long has felt one.  In fact, Alaska is one of the most seismically active places on Earth.  On average, Alaska experiences 35,000 earthquakes a year, which is over 10% of all the earthquakes in the entire world.  (External link-  See the location, size, and depth of all the earthquakes in Alaska over the last 2 weeks)

Alaska does not just get a lot of earthquakes; it also has big ones!  Three of the six largest earthquakes in recorded history have been in Alaska, including the famous 1964 Good Friday Earthquake, which was the second largest recorded. More recently, in 2016 and 2018, magnitude 7 earthquakes in the Cook Inlet region caused widespread damage to Southcentral Alaska.  On average, Alaska has one "great" earthquake (magnitude 8 or larger) every 13 years.  

A by-product of earthquakes can be tsunamis. When an earthquake happens under the ocean, the sudden movement of the ocean floor can create a tsunami wave.  These tsunami waves can be extremely dangerous.  In the 1964 Good Friday Earthquake, 15 people died directly in the earthquake, but 124 died in the resulting tsunamis (18 of these in California and Oregon).

Interested in learning more about Alaska tectonics and earthquakes, check out this video: https://www.youtube.com/watch?v=hEW0jMW1vbY