How was the waterfall created?
When a river flows over a layer of hard rock, the softer rocks are more quickly eroded down-stream from the harder rock. The river bed becomes steeper and rapids develop as the water flows quickly over rocks and bolders.
As the softer rock is worn away (eroded) more quickly a steep waterfall begins to form. A steep back-wall is formed. Water starts to fall over the harder rock further eroding the softer rock below. As the softer rock is worn aeay the waterfall creates a plunge pool into which water falls.
If you want to log this cache, you have to complete two tasks:
1) how big is (approximately) water fall?
2) take a picture of you in front of the water fall and upload the image to your log (if you are as courageous as we were, take the picture of you inside the plunge pool :))