What caused the Indonesia tsunami and earthquake? Scientists still aren't sure

Emergency relief measures are still ongoing in Indonesia, where a magnitude 7.5 earthquake and ensuing tsunami has caused massive damage on the island of Sulawesi. Read about why scientists are still unsure about the ultimate cause of the catastrophic event in this piece by the BBC.

You may also read more about the process of liquefaction (where the ground suddenly behaves like a liquid instead of a solid) here.

We have also compiled videos about the science of tsunamis and earthquakes that will help explain these natural disasters in visual terms.