Question: What is the most unusual way the ground beneath a train has behaved?

Natalie Wride answered on 13 Jun 2016:

Hi Elllxox!

This is a great question – a lot of people think the ground can only behave in one way but it all depends on the type of soil and the amount of water in it!

I think the most unusual way (and it’s the most interesting to watch happen!) is called Liquefaction. This is a super long word which means the soil turns to a liquid. It sounds really weird – and it is! You might have heard of this in your Geography lessons when you study earthquakes? The same thing can happen under lots of vibrations from the train passing over the ground.

You can see a couple of (extreme!) pictures of damage due to liquefaction from earthquakes in Japan below:

https://upload.wikimedia.org/wikipedia/commons/4/42/Liquefaction_at_Niigata.JPG
Can you see all the blocks of flats tilting because the soil underneath them has turned soft?!

Here’s a video of an earthquake in Japan – you can see the ground moving and it looks really scary! I don’t think I’d of liked being there. You can see all the water pumping up through the ground when the ground turns all slushy!

You can do your own experiment to see it happen at home if you want! If you fill a water bottle or a tray with some soil and a bit of water and shake it up or stir it to mix it all together. Then leave it to stand on a table. Then give the table a shake again, you see the soil becomes really ‘slushy’ – this is liquefaction!

Hope this answers your question! Let me know if you have any more – and if you give the experiment a go 🙂