Tsunamis are caused by energy originating underwater from a volcanic eruption, a submarine landslide, or, most commonly, an earthquake on the ocean floor.

1. For example, the tectonic plates of the Earth’s surface slip, releasing a massive amount of energy into the water. 2. This energy travels up to the surface, displacing water and raising it above the normal sea level.

3. Gravity pulls that energy back down.

4. As a result, the energy ripples outwards horizontally. Thus, the tsunami is born, moving at over 500 miles per hour.  

From the TED-Ed Lesson How tsunamis work - Alex Gendler

Animation by Augenblick Studios


the silfra canyon of the mid atlantic ridge in iceland’s thingvellir national park has on one side the north american plate and on the other side the eurasian plate. the two plates are moving apart, widening the size of the atlantic ocean by about an inch a year. 

the water’s clarity, it bears noting, is the result of melted glacier water from langjoekull, which is filtered through underground lava rocks.

photos by chad copeland, magnus lundgren and alexander mustard

This image shows Earth’s tectonic plates, and the location of earthquakes and volcanic activity along the plate boundaries. 

What causes earthquakes, and why are they so unpredictable? Seismic waves that pass through the planet hold the answer to these questions. Their patterns can reveal hidden dynamics—hotspots, deep-diving rock, melting mantle—in Earth’s interior. 

Watch a video featuring the group that is installing seismometers across the United States, and check out our SeismoDome event, happening tonight in the Hayden Planetarium.

This was over before it started.
The fault lines should have warned us,
but we stepped around them.
Do you understand Pangaea now?
How land masses that fit so perfectly
can float away until they are different continents
with different languages?
You probably don’t remember that this
almost worked out.
But it just had to happen this way.
Tell me,
do you believe in poetry yet?
Is it because you are tasting it in someone else’s mouth?
Don’t answer that.
I am sending this message in a bottle,
and I don’t want it to reach you.
It wouldn’t be fair
to let you think you can still choose.
This is just for me,
so I can know how horrible this
all sounds out loud.
For the record, it’s not good.
But the parts of me that held on to you
will erode away soon,
and I will stop reaching for them.
Some earthquakes will still remind me
of all that was lost,
but I am willing to shake my bones if it means
getting you out of my blood.
—  Y.Z, Tectonic plates

The last 600 million years of Earth’s continental evolution in 10 images:

  1. 600 Ma: Ediacaran
  2. 500 Ma: Cambrian
  3. 400 Ma: Devonian
  4. 300 Ma: Carboniferous
  5. 220 Ma: Triassic
  6. 150 Ma: Jurassic
  7. 90 Ma: Cretaceous
  8. 50 Ma: Palaeogene
  9. 20 Ma: Neogene
  10. Present: Quaternary

Source + more

This is a picture I took with my phone at the Naturalis Biodiversity Center in Leiden, Netherlands. It is a scale showing how 1L (liter) of granite is lighter than 1L of basalt. This helps us visualize why plate tectonics never results in continents sinking underneath the ocean. Because continental crust is made of granite and oceanic crust is made of basalt, continents will never sink under the ocean because continents are always lighter than the ocean floor.

The pen is there for scale.