MP3 4 Weeks Study Guide

Rock can change from one form to each of the other forms. Describe two ways in which igneous rocks can form.

• Metamorphic rock can melt and recrystallize to become igneous rock.

• Igneous rock weathers and lithifies to form sediments.

• Igneous compacts and cements to form magma.

• Sedimentary rock can melt and recrystallize to become igneous rock.

Answer explanation

Igneous rocks can form through magma cooling beneath the Earth's surface, creating intrusive rocks, or through lava cooling on the surface, resulting in extrusive rocks. Both processes involve the solidification of molten material.

Place the processes in the formation of sedimentary rock in the correct order.

• weathering, erosion, deposition, compaction

• erosion, weathering, deposition, compaction

• deposition, weathering, erosion, compaction

• compaction, weathering, erosion, deposition

Answer explanation

The correct order is weathering (breaking down rocks), erosion (transporting sediments), deposition (laying down sediments), and compaction (pressing sediments together). Thus, the right choice is 'weathering, erosion, deposition, compaction'.

Metamorphic rock is formed through _______ and _______.

• heat, pressure

• compaction, cementation

• melting, cooling

• weathering, erosion

Answer explanation

Metamorphic rock is formed through heat and pressure, which alter existing rocks without melting them. This process distinguishes metamorphic rocks from those formed by compaction, cementation, melting, or erosion.

Use the rock cycle diagram to complete the following statements by moving the answers to the correct boxes. Rock A would be identified as a _______ rock because they form by being compacted and cemented together.

Answer explanation

Rock A would be identified as a sedimentary rock because sedimentary rocks form through the processes of compaction and cementation of particles and organic materials.

Use the rock cycle diagram to complete the following statements by moving the answers to the correct boxes. Rock B would be identified as a _______ rock because they are formed when magma from a volcanic eruption cools down.

Answer explanation

Rock B would be identified as an igneous rock because igneous rocks are formed when magma cools and solidifies, typically after a volcanic eruption.

The model of the rock cycle below represents how minerals undergo changes to create different types of rocks. When magma cools down, what type of rock will it become?

• Sedimentary

• Igneous

• Metamorphic

• Sediment

Answer explanation

When magma cools down, it solidifies to form igneous rock. This process is fundamental in the rock cycle, distinguishing igneous rocks from sedimentary and metamorphic types.

A student wanted to make a model of the Earth. The student decided to cut a giant Styrofoam ball in half and paint the layers on it to show their thickness. Which model below best represents the layers of the Earth?

• 
• 
• 
• 

Answer explanation

Model C best represents the layers of the Earth, showing the core, mantle, and crust with appropriate thicknesses. The other options do not accurately depict these layers or their relative sizes.

Models are great ways of representing complex ideas with a simple representation. An example of this is the model below of the layers of the Earth. In the diagram, how is the heat being transferred?

• Convection

• Conduction

• Radiation

• Specific

Answer explanation

Heat is transferred in the Earth's layers primarily through convection, where hot material rises and cooler material sinks, creating a continuous cycle. This process effectively distributes heat within the Earth's interior.

Which of the following layers is labeled as A?

• outer core

• crust

• inner core

• mantle

Answer explanation

The inner core is the innermost layer of the Earth, composed primarily of iron and nickel. It is solid due to the immense pressure, distinguishing it from the outer core, which is liquid.

Which of the following statements is true of the four spheres of Earth?

• The hydrosphere and biosphere are closely linked, but the atmosphere and geosphere are not.

• The four spheres of Earth are very closely connected and a change in one often affects another.

• The geosphere, atmosphere, and hydrosphere are very co-dependent, but the biosphere is unrelated to the others.

• The four spheres of Earth are strictly independent entities and no interactions take place between them.

Answer explanation

The correct statement highlights that the four spheres of Earth—atmosphere, hydrosphere, geosphere, and biosphere—are interconnected. Changes in one sphere can significantly impact the others, demonstrating their interdependence.