Earth Science

Erosion

What is Erosion?

  BREAK IT DOWN

Erosion is the process that breaks things down. Erosion is the breakdown of the continents and the land around you. Erosion of landforms is caused by running water, frozen water, and wind. In nature, large things are broken down into smaller things. Boulders become sand. Mountains are rained on, erode and become hills. ErosionErosion causes pieces of the mountain to become smaller pieces and go down

the sides of hills. Erosion always happens in a downhill direction.

You Can Make Erosion Happen! How????? Pretend you are hiking in the mountains. You pull a rock from the side of the mountain, then throw it down into a

canyon. You are now a part of the erosion of that mountain. You have taken a big object (a mountain) and started to make little

objects out of it (a rock). When that rock hit the ground, it could have cracked and made some

tiny pieces of rock (sand).

Mass Wasting

Do you ever wonder where rocks and sand go ? Things don't just disappear. The masses of dirt and rock are moved to

another form and place. The wasting is the loss of matter in one place. Mass wasting can happen two ways: 1) mechanical, similar to breaking a rock with a hammer; and 2) chemical, similar to pouring acid on a rock to dissolve it. Erosion happens at the tops of mountains and under the soil. Water

and chemicals get into the rocks and break them up through those mechanical and chemical forces. Erosion in one area can actually build up lower areas. Think about a mountain range and a river. As the mountain erodes, the river carries sediment downstream towards the ocean. That sediment slowly builds up and creates new wetlands at the mouth of the river.

Mechanical Weathering

Mechanical weathering is the process of breaking big rocks into little ones.

This process usually happens near the surface of the planet. Temperature also affects the land. The cool nights and hot

days always cause things to expand and contract. That movement can cause rocks to crack and break apart.

Roots and plants also push into the rocks and break them apart. They act like wedges and push the rocks apart. Little animals also help by burrowing and digging through the ground.

The Landscape Around Us

VASQUEZ ROCKS IS A SANDSTONE ROCK FORMATION ERODED BY WIND AND WATER. YOU CAN FIND THIS

COLLECTION OF ROCKS BY DRIVING TO AGUA DULCE (WHICH IS VERY CLOSE TO OUR SCHOOL).

Yosemite Valley is a landform created by glaciers. (frozen water)

The glacier’s force is able to gouge out huge chunks of rock and soil from the earth.

As the glacier pushes its way through the mountains it creates U-shaped valleys called moraines.

Half Dome was once a “full dome”-until a glacier made its way through it!!!

The Grand Canyon in Arizona is a landform created by running water erosion

Our World is always changing . Erosion is always taking place.