Download this free classroom poster to help your geography students understand how waterfalls are formed.
We’ve created this free waterfalls poster to help your students better understand how these spectacular features of river landscapes are formed.
How are waterfalls formed?
Waterfalls usually form in the upper stages of a river. As the river flows over bands of different rock, the water erodes soft rock more quickly than hard rock.
This undercuts the hard rock and leaves it overhanging. Because it is no longer supported by the soft rock, it eventually collapses.
When the hard rock overhang collapses, it falls into the plunge pool at the bottom of the waterfall. As it breaks up and the fragments swirl around, the rock causes more erosion.
The process is repeated over time and moves the waterfall further and further upstream.
As the waterfall retreats, a steep-sided gorge is formed.
See waterfalls in action!
We offer a number of geography school trips that offer the exciting opportunity to see waterfalls in action. Iceland, in particular, offers the opportunity for some fantastic waterfall experiences.
We have some fantastic videos of the waterfalls in Iceland in our Experience Geography in Action resource.
Skogafoss is one of Iceland’s largest waterfalls, with a width of 25m and a drop of 60m. As you can walk right up to the wall of water, this is a great opportunity to see a waterfall up close.
Even better is nearby Seljalandsfoss, where visitors can walk behind the waterfall itself.
And spectacular Gullfoss is actually made up of two steps – the first cascade has a drop of 11m and the second cascade has a drop of 21m. This gives students an opportunity to see a different type of waterfall.
Need more information?
Please don’t hesitate to contact us for further information or to request a tailor-made quote.