Earth Science

The natural chemical or physical processes that breaks down rock on Earth's surface.

• weathering
• erosion
• deposition
• jackhammering

The process by which water, ice, wind or gravity moves weathered rock and soil from one place to another.

• weathering
• erosion
• deposition
• dumptruck

What is mechanical weathering?

• Process through which rocks are physically broken into smaller pieces.
• Rocks are broken down through chemical changes.
• Rocks are worn away from acid in plant roots.
• Rocks broken down by machinery.

Rust that forms on rocks or metal because of extended exposure to oxygen is what example of chemical weathering?

• carbon dioxide (carbonic acid)
• acid rain
• oxygen
• living organisms

How does freezing water cause the weathering of rocks?  The freezing water—

• keeps the rocks in place
• makes the rocks last longer
• expands cracks and breaks rocks
• causes rocks to fall in landslides

Weeds growing into the cracks in a sidewalk and the sidewalk begins to crumble is an example of:

• mechanical weathering
• chemical weathering

What is the process that picks up and moves weathered rocks?

• deposition
• landslide
• weathering
• erosion

How are canyons formed?

• Wind blows sand into high piles, which form the canyon walls.
• Rivers erode soil and rock over time, leaving behind canyon walls.
• Gravity causes rocks to fall from mountain sides onto valley floors.
• Ice freezes and thaws in cracks of rocks, and the cracks become canyons.

A cliff formed near the ocean.  Which statement best describes how this cliff formed?

• Warm air melted the rock.
• Sun rays evaporated the rock.
• Ocean waves washed away rock.
• Plant roots pushed away the rock.

Over long periods of time, deposition may change the Earth’s surface by _____.

• forming new land features
• breaking down large rocks into smaller ones
• washing away beaches
• severely draining topsoil