Weathering, Erosion, Rocks, and Minerals

Which of the following is an example of erosion?

• Wind beats against a rock causing it to break into pieces

• A plant's roots grow into the cracks in a rock, causing it to break apart

• A river carries bits of rock and soil away from the riverbanks to the ocean

•  Water freezes within a crack in a rock which expands and widens the crack.

Earth has a great variety of surface features that are caused by weathering and erosion.

Which of the following describes a change due only to weathering?

• tree roots breaking rocks into smaller pieces of rock

• wind blowing sand and pebbles off of a sand dune

•  rivers carrying soil and rocks through valleys

• ocean waves washing sand off the beach

Water seeps into a tiny crack in a rock. The water freezes and expands, pushing against the sides of the crack. The rock breaks apart.

What is this an example of?

• weathering

• glaciers

• erosion

• gravity

Natural processes affect rocks and soil. The land is always changing. What is

the main difference between weathering and erosion?

•   Weathering involves breaking down, while erosion involves the movement of material.

•  Weathering only involves wind, while erosion only involves water.

• Weathering involves weather, but erosion does not

• Weathering can involve ice, but erosion does not.

Many rocks contain gaps or cracks. In the diagram below, notice the relationship between rock and the plant.

Which statement describes what will happen to the rock and the plant over time?

• The rock will crush the plant.

• The plant will be buried in the crack.

• The rock will stop the plant from growing bigger.

• The plant will grow, and the cracks will get bigger.

Rocks often show bands of different minerals. What type of rock is formed under extreme pressure and heat?

•   igneous

• volcanic

•  metamorphic

• sedimentary

Josephine found a mineral while hiking. To help identify the mineral she took a small ceramic tile and dragged the mineral across it.

What was she trying to accomplish by dragging the mineral across the tile?

• She wanted to see if the mineral had a shiny luster.

• She wanted to compare the color of the mineral to the color of the tile.

• She wanted to break the mineral so that she could check the cleavage pattern

• She wanted to see the color of the powder that the mineral would make on the tile

Luann's uncle is a geologist. She asked him about the difference between rocks and minerals. Which of the following would be a correct statement to determine the difference between rocks and minerals?

• Rocks are often made of many different minerals mixed together.

• Minerals can no longer be identified once they are part of a rock.

• Minerals are often made of many different rocks mixed together.

•  Rocks are made of only one kind of mineral, such as quartz.

Limestone is a common rock found in Florida. It forms when water erodes clay, silt, and sand. Fossils are often found in limestone. What is limestone?

• an igneous rock

• a sedimentary rock

• a metamorphic rock

• a mineral

Dennis cannot scratch a mineral with his fingernail, but he observes that he can scratch the mineral sample with a piece of metal. Which physical property of the mineral sample is Dennis investigating?

• hardness

• Cleavage

• Streak

•  Luster