Earth Science SLO (Weathering and Erosion)

David, Luna, and Arjun are exploring rocks on a chilly morning. They notice that after a cold night, water that had seeped into small cracks in a rock has frozen. What do you think happens to the rock when the water freezes? The freezing water—

• keeps the rocks in place

• makes the rocks last longer

• expands cracks and breaks rocks

• causes rocks to fall in landslides

Answer explanation

Freezing water expands in cracks of rocks, exerting pressure that can cause the rocks to break apart. This process, known as frost wedging, is a key mechanism in the weathering of rocks.

Grace and Nora are exploring Nora's backyard when they notice that some rocks have started to weaken and break down. They discover that this is happening because of chemical changes in the rocks. The type of weathering Grace and Nora are observing is (a)  

• mechanical weathering
• chemical weathering
• erosions weathering
• deposition

Answer explanation

Chemical weathering occurs when rocks undergo chemical changes that weaken and break them down, making it the correct choice. In contrast, mechanical weathering involves physical breakdown without altering composition.

Ava, Henry, and Harper are helping their teacher in a science class by sorting different types of soil particles. They come across sand, clay, loam, and silt. Can you help them figure out which one is not a soil particle?

• sand

• clay

• loam

• silt

Answer explanation

Loam is not a soil particle; it is a mixture of sand, silt, and clay. Sand, clay, and silt are individual soil particles, while loam represents a combination of these particles.

While hiking with Aria and Jackson, Kai notices that pieces of rock along the trail have broken down into smaller fragments, but their chemical composition stays the same. What type of weathering are they all observing?

• mechanical weathering

• chemical weathering

• erosions weathering

• deposition

Answer explanation

Mechanical weathering is the process where rocks are physically broken down into smaller pieces without changing their chemical composition, making it the correct choice for this type of weathering.

Benjamin, Ava, and Rohan are planning an adventurous hiking trip and want to explore mysterious caves formed by the dissolution of rocks. Which type of rock should they look for if they want to discover amazing Karst topography?

• Limestone

• Sandstone

• Granite

• Coal

Answer explanation

Limestone is the most susceptible rock type to karst topography due to its solubility in acidic water, leading to features like caves and sinkholes. Other rocks like sandstone, granite, and coal do not exhibit this characteristic.

Daniel, Grace, and James are helping Benjamin design a garden path. They want to make sure water drains well, so they're picking the best soil for the base. Which of the following materials would have the lowest porosity, making it the worst choice for water drainage?

• Clay

• Silt

• Gravel

• Sand

Answer explanation

Clay has the lowest porosity among the options because its fine particles pack closely together, leaving less space for air or water compared to silt, sand, and gravel, which have larger particles and more voids.

Match each process with its correct description related to how rocks change in the environment.

• The process where outer layers of rock peel away due to temperature changes.

• Weathering

• The process by which sediments are laid down in new locations.

• Exfoliation

• The process where rocks are broken down and changed by rain and wind.

• Transportation

• The movement of rock particles from one place to another.

• Deposition

Answer explanation

The correct answer is Weathering, which refers to the process of breaking down and changing rocks at or near Earth's surface due to various factors like wind, water, and temperature changes.

Aria, Ethan, and Lily are on a rock-hunting adventure! As they explore different places, they notice that some rocks crumble and break down much faster than others. They wonder: what is usually the main reason that rocks weather at different rates in different areas?

• Topography

• Volume

• Climate

• Biological organisms

Answer explanation

Climate is the primary factor affecting weathering rates, as it influences temperature, precipitation, and humidity, which in turn affect chemical and physical weathering processes.

Maya, Michael, and Daniel are investigating what makes rocks in their backyard weather faster or slower. (a)   does not affect how quickly rocks weather.

• Rock type
• Rock composition
• Climate
• Fossils

Answer explanation

Fossils do not contribute to the rate of weathering. Weathering is influenced by rock type, composition, and climate, which affect how rocks break down over time.

Aria, Evelyn, and Arjun are hiking together on a steep mountain trail when they suddenly see rocks and soil sliding down the slope! The group wonders: what is the powerful force behind all forms of mass movements like this?

• Friction

• Gravity

• Magnetism

• The Coriolis Effect

Answer explanation

Gravity is the fundamental force that pulls objects toward each other, causing all forms of mass movement, such as landslides and avalanches. It is the primary driver behind these processes, unlike friction, magnetism, or the Coriolis Effect.