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Nature is a fantastic sculptor.
The same process that did this, also made these and this.
It's a process called weathering.
Weathering
In desert regions, rocks expand slightly in the day as they are heated by the Sun, and then shrink a little at night as they cool down.
This daily cycle of expansion and contraction weakens the surface of the rock causing it to fragment and break into smaller pieces.
Water can also cause weathering.
It can penetrate tiny cracks in rocks.
If it gets cold enough, the water expands as it turns to ice, causing the rock split apart.
In a similar way, plants can cause weathering too.
When their roots grow into cracks, they force the cracks to widen, causing the rock to break into smaller fragments.
So, weathering is the breakdown of rock into smaller pieces.
weathering
breakdown of rock
into smaller pieces
Rocks broken down by weathering will eventually become part of the soil, unless they are eroded first.
Erosion
Erosion is the removal of weathered rock and soil.
erosion
removal of weathered rock and soil
Erosion can happen in many different ways.
Over time rivers erode riverbeds and banks.
Coastal soils are constantly eroded by waves.
Further inland, the wind can remove weathered rock and soil.
Humans and other animals are also powerful tools of erosion.
So it's weathering that breaks rock down, and erosion that removes weathered rock and soil.
Both are natural processes that can dramatically shape the landscape.
weathering
erosion
Nature is good at making sculptures.
The same process that made this… also made these… and this.
It is a process called weathering.
Weathering
When rocks are heated by the Sun, they get a little bit bigger. We say that the rocks expand. When rocks cool down at night, they get a little bit smaller. We say that the rocks contract.
The rocks expand and contract every day. Over time, this damages the surface of the rock. The rock breaks into smaller pieces.
Water can also cause weathering.
It can get into very small cracks in rocks.
If it gets cold enough, the water turns into ice. It expands and causes the rock to break apart.
Plants cause weathering too.
Their roots grow down into cracks. This makes the cracks bigger. The rock breaks into smaller pieces.
So, weathering breaks rocks into smaller pieces.
weathering
breakdown of rock
into smaller pieces
Rocks that have been broken down by weathering eventually become part of the soil, unless they are eroded first.
Erosion
Erosion is the removal of weathered rock and soil.
erosion
removal of weathered rock and soil
Erosion can happen in many different ways.
Rivers erode riverbeds and banks.
Waves erode the coast.
The wind can remove weathered rock and soil.
Humans and other animals also cause erosion.
So, weathering breaks rocks into smaller pieces. And erosion removes weathered rock and soil.
Weathering and erosion are natural processes. They can dramatically change the landscape.
weathering
erosion