Chile Quake Changed Earth's Rotation ... probably.

From Space.com:  The massive 8.8 earthquake that struck Chile may have changed the entire Earth's rotation and shortened the length of days on our planet, a NASA scientist said Monday. The quake, the seventh strongest earthquake in recorded history, hit Chile Saturday and should have shortened the length of an Earth day by 1.26 milliseconds.  Read this story here.

Tsunami

With the recent earthquake in Chile and subsequent Tsunami alarms across the Pacific Ocean, you may be wondering how a tsunami forms.  There is an excellent and lengthy description here.

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Tsunamis are formed as a result of earthquakes, volcanic eruptions, or landslides that occur under the sea. When these events occur under the water, huge amounts of energy are released as a result of quick upward bottom movement. For example, if a volcanic eruption occurs, the ocean floor may very quickly move upward several hundred feet. When this happens, huge volumes of ocean water are pushed upward and a wave is formed. A large earthquake can lift thousands of square kilometers of sea floor which will cause the formation of huge waves. The Pacific Ocean is especially prone to tsunamis as a result of the large amount of undersea geological activity.

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