Surface Process - Erosion

What is erosion?

The wearing away of the Earth's landscape.

What feature of river erosion is found in the youthful stage of a river?

A waterfall.

What initiates the formation of a waterfall?

The erosion of rock and soil by water flow.

What factors influence the erosion that leads to waterfall formation?

The force of the water, the type of rock and soil, and the amount of precipitation.

How do harder rocks like granite compare to softer rocks like sandstone in terms of erosion?

Harder rocks are more resistant to erosion than softer rocks.

What is differential erosion?

The process where soft rock erodes faster than hard rock due to hydraulic action.

What is created as a result of differential erosion in waterfall formation?

A notch or dip in the soft rock, leading to the formation of an overhang.

What happens to the back wall of the overhang during waterfall formation?

It is deepened by the splashing of the falling water, eventually causing the overhang to collapse.

What is headward erosion?

The upstream retreat of a waterfall, resulting in the creation of a steep

What is a plunge pool?

An over

How does eddying contribute to the formation of a plunge pool?

It increases the depth of the plunge pool by swirling pebbles trapped in hollows.

What role does climate play in waterfall formation?

High precipitation rates increase water flow and erosion, while low rates decrease them.

What geological processes can lead to waterfall formation besides river erosion?

Glaciation and tectonic uplift of plates.

What is isostasy in relation to waterfall formation?

It can cause a knickpoint or sudden drop in a river's profile, leading to increased vertical erosion.

Give an example of a waterfall formed at a knickpoint.

Kathleen's Falls on the River Erne in Ballyshannon, Co. Donegal.

What is the significance of the type of rock present in waterfall formation?

It affects the shape of the waterfall, with harder rocks creating vertical drops and softer rocks leading to gradual slopes.

What happens to a waterfall as it retreats upstream?

It creates a gorge due to headward erosion.

What is the primary cause of erosion in waterfall formation?

The force of moving water.