How have megaquakes shaped our planet?

When compared to the events in Week 1, even the largest megaquakes seem insignificant.

But their impact on the planet hasn’t been insignificant. Earthquakes are the mechanism by which tectonic plates move across the Earth’s surface.

The gradual stop and go motion of earthquakes moves plates at speeds of 2 to 5 centimeters per year. About the same rate as your fingernails grow. This means that over the average human lifetime, plates will have moved several metres only.

Megaquakes over geological timescales

On geological timescales of millions to hundreds of millions of years, the plates will have moved thousands of kilometers. About 250 million years ago all the continents we know today were attached together and formed a single supercontinent, called Pangaea.

Diagrams that show the supercontinent Pangaea on a world map during the Permian geological time period 250 million years ago, next showing a further break up of the continent during the Triassic geological time period 200 million years ago, next showing a further break up of the continent during the Jurassic geological time period 145 million years ago, next showing a further break up of the continents during the Cretaceous geological time period 65 million years ago, finally showing the position of the continents on a world map at present day

Continental drift by USGS, Public Domain

Over geological timescales the constant activity of earthquakes and more significantly megaquakes, brings continents together and tears others apart. This has an immense influence on the evolution of life.

Continents that are isolated for long periods of time such as Australia or Oceania develop entirely different fauna and flora than in other places.


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Extreme Geological Events

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