Earth's Structure and Plate Tectonics

Lina is studying different isotopes. She drew the diagram below to show a relationship between carbon-14 and nitrogen-14.

What is the correct process shown above?

• absolute decay

• radioactive decay

• relative dating

• unconformity

The figure shows part of what scientists think is happening in Earth’s mantle.

What process does the figure show occurring in the mantle?

• Hot rock expands, becomes less dense, and rises toward the surface of Earth.

• Hot rock expands, becomes more dense, and rises toward the surface of Earth.

• Hot rock becomes less dense and moves towards the outer core.

• Hot rock becomes more dense and moves towards the lithosphere.

The motion of tectonic plates can cause both slow and rapid changes in Earth’s surface. Which is an example of a rapid change?

• earthquake

• seafloor spreading

• mountain range formation

• formation of an ocean trench

It might seem that, since the surface of the Earth is a fairly moderate temperature, Earth's core would also be of a fairly moderate temperature. Using creative logic, scientists have determined that material below the surface of the Earth is liquid and very hot. Which event on the surface of the Earth would support that conclusion?

• an earthquake

• an erupting volcano

• the temperature of the ocean water

• high surface temperature in the deserts

Earth’s temperature increases with depth. Which of the following is a result of the motion of materials caused by high temperatures in Earth’s mantle?

• earthquakes and volcanoes

• radioactive atoms in minerals

• ocean tides

• erosion and deposition

Basalt forms when lava cools on Earth’s surface. Granite forms when magma cools within the Earth. Which of these statements correctly classifies both basalt and granite?

• Basalt and granite are both igneous rocks.

• Basalt and granite are both metamorphic rocks.

• Basalt is igneous rock, and granite is metamorphic rock.

• Basalt is metamorphic rock, and granite is igneous rock.

Earth’s surface features slowly change over time. For example, sharp, jagged mountain ranges become lower and more rounded over time. What factor(s) is responsible for this change in their shape?

• weathering and erosion

• depostion

• movement of continents

• collisions between continental plates

Mr. Forester’s classroom has a thermometer in the window. At 1 p.m., Rina, Pedro, and Meenu read the thermometer and record the temperatures on a chart. After a week, Mr. Forester puts the students’ findings into another chart. See table for the results:

Which of these variables might account for the differences in the recorded temperatures?

• time of day

• changing weather

• amount of sunlight

• ability to read the thermometer

Evelyn is making a model of Earth to show how the physical layers correspond to the compositional

layers. Which of the following should Evelyn show in her model?

• The physical layers exactly match the compositional layers.

• The crust is the only compositional layer not included in the physical layers.

• The physical layers of the inner core and outer core form a single compositional layer.

• The physical layer of the asthenosphere includes the compositional layer of the crust.

A geologist is studying three layers of sedimentary rock in an area. The layers have not shifted from their original positions. The geologist records the relative ages of the rocks. The bottom layer is listed as the oldest. The top layer is listed as the youngest. What did the geologist use to determine the relative ages of the rocks?

• mineral content

• radioactive decay

• the law of superposition

• the principle of unconformity