Unit 2: Earth's Processes

Moving pieces of the lithosphere are responsible for ________.

• Sea floor spreading

• Volcanoes

• Earthquakes

Answer explanation

Moving pieces of the lithosphere, or tectonic plates, create stress along faults, leading to earthquakes. While they also contribute to sea floor spreading and volcanoes, the direct result of their movement is most notably earthquakes.

Which of these is a surface wave from an earthquake?

• A

• B

• C

Answer explanation

Surface waves are seismic waves that travel along the Earth's surface. Choice B represents a type of surface wave, while A and C do not. Therefore, B is the correct answer.

A geologist is unable to scratch a mineral with his fingernail or a copper penny, but he can scratch it with a steel nail. Of these choices, the mineral is probably:

• Talc (hardness = 2)

• Fluorite (hardness = 4)

• Feldspar (hardness = 7)

Answer explanation

The mineral cannot be scratched by a fingernail (hardness < 2) or a copper penny (hardness = 3), but can be scratched by a steel nail (hardness = 5). Thus, the mineral is likely Fluorite, with a hardness of 4.

Which of the following is the most likely reason the oxbow lake (in the picture at right) formed?

• The moving water from the meandering river eroded the banks until part of the river was pinched off to form a lake.

• A tornado moved through the area and relocated the riverbank.

• A drought dried the original river; when enough rain came the river was replenished and the lake formed next to it.

Answer explanation

The correct choice explains that the oxbow lake formed due to the erosion of riverbanks by the moving water of a meandering river, which pinched off a section of the river, creating the lake.

What is the relationship between the number of mudslides and the number of deaths in Nepal?

• More landslides = higher death rate

• More landslides = lower death rate

• There is no relationship between the number of landslides and death rate

Answer explanation

In Nepal, an increase in the number of mudslides typically leads to a higher death rate, as more landslides can result in more casualties due to their destructive nature.

Why are mudslides so dangerous?

• The flow is very thick and hard to escape from

• The flow is very fast and can sweep people away quickly

• Landslides tend to contain sharp pieces that can do a lot of damage

Answer explanation

Mudslides are particularly dangerous because their flow is very fast, allowing them to sweep people away quickly before they can react. This rapid movement poses a significant risk to anyone in the vicinity.

According to the graph above, what was the first year when more than 50% of Japanese schools were earthquake resistant?

• 2005

• 2007

• 2009

Answer explanation

The graph indicates that in 2009, the percentage of earthquake-resistant schools in Japan surpassed 50%. Prior years, such as 2005 and 2007, did not reach this threshold, making 2009 the correct answer.

What type of plate boundary is shown in the first diagram?

• Convergent

• Divergent

• Transform

Answer explanation

The first diagram depicts a divergent plate boundary, where tectonic plates move apart, allowing magma to rise and create new crust. This process is characteristic of divergent boundaries, distinguishing it from convergent and transform boundaries.

Would there be volcanoes at a divergent boundary?

• Yes

• No

Answer explanation

Yes, there would be volcanoes at a divergent boundary. This is where tectonic plates move apart, allowing magma to rise and create new crust, often resulting in volcanic activity.

What process can turn a metamorphic rock into an igneous rock?

• Melting and cooling

• Weathering and erosion

• Compaction and cementation

Answer explanation

Metamorphic rocks can transform into igneous rocks through the process of melting and cooling. When metamorphic rocks melt, they form magma, which, upon cooling, solidifies into igneous rock.