Plate Tectonics and Landform Patterns

In this lesson, students analyze how Earth’s surface has changed over time, powered by energy from the sun and Earth’s interior. They evaluate how the locations of various landforms, including mountains, valleys, and volcanoes, occur in patterns because of how Earth’s interior layers interact and change. 

• Scientists study Earth’s structure to learn about how Earth has changed over time. 
• Like all terrestrial objects, including the terrestrial planets and moons, Earth’s surface is made up of rocks, which are mixtures of minerals.
• Earth is a dynamic planet because Earth’s internal structure causes changes on the surface over time.
• Many of Earth’s surface features and events are caused by the movement of tectonic plates.  
• There is a cause-and-effect relationship between the movement of tectonic plates and the resulting landforms and surface events. This cause-and- effect relationship causes patterns in the locations of those landforms and events.
• Tectonic plates move because they are pushed and pulled by semi-solid magma that makes up Earth’s mantle and flows in currents beneath the crust.
• Earthquakes and volcanoes often occur in similar locations because they are caused by the same forces.

• Why do minerals have different properties?
• How do tectonic plates fit into Earth’s structure?
• What is the relationship between tectonic plates, oceans, and continents?
• What surface events are caused by convergent plate boundaries? What surface events are caused by divergent plate boundaries?
• Why are mountain ranges common along the edges of the continents?
• Why do earthquakes and volcanoes often occur in similar locations?  
  
  

Misconception: Earth’s surface is static and does not change.

Fact: Earth’s surface is constantly changing. Plate tectonics, weathering, and erosion are three processes that change Earth’s surface over time.

Misconception: Earth’s landforms, such as mountains and valleys, occur randomly around the planet.

Fact: Mountains and valleys are formed by interactions of Earth’s tectonic plates, so there are patterns in their locations, which often correspond to plate boundaries.

Convergent boundary: a plate boundary formed when two tectonic plates move toward one another perpendicular to the fault line

Divergent boundary:  a plate boundary formed when two tectonic plates move apart from one another perpendicular to the fault line

Rock cycle: the processes that form, break down, and re-form rock from one category to another

Rocks: mixed mineral matter that makes up the surface of Earth and other terrestrial objects

Sediment:  a collection of particles of rocks, minerals, and the remains of plants and animals

Tectonic plates: drifting slabs of solid rock, called plates, that make up Earth’s surface

Transform boundary: a plate boundary formed when two tectonic plates slide past each other in parallel, grinding along their sides as they move

Weathering: the breakdown of rock into smaller pieces from exposure to wind, water, gravity, changes in temperature, and/or biological forces

The Grand Canyon

The Grand Canyon is one of the deepest and widest canyons in the world. It is so large that it can be seen from space. At its widest, it is 29 kilometers (18 miles) across. It is 446 kilometers (277 miles) long and more than 1.6 kilometers (1 mile) deep.

The canyon holds clues to Earth’s past going back two million years. Like detectives, scientists study the properties of the rocks that make up the Grand Canyon.

These rocks tell a story about how they were formed and what the environment was like when they formed. By studying the rocks, scientists have learned that Earth’s surface is always changing.

Properties of Rocks

The Grand Canyon is made up of many different kinds of rock. Rocks make up the surface of Earth and other terrestrial objects, including planets and moons. They are kinds of matter made up of mixtures of different minerals.

Minerals are naturally occurring. This means they are not made by humans. They would exist on Earth without people.

Minerals are inorganic. This is because they are not the product of something that is living or was once alive. Leaves and shells are organic because they come from something that was once alive.

Minerals also have a definite chemical composition. This means that every mineral is made up of the same kind and number of atoms. Lastly, minerals have an orderly crystal structure. This means their atoms are neatly organized to form a repeating pattern.

When minerals are pressed together by heat and pressure, they can combine to form different kinds of rock.

A Changing Planet

The clues in Earth’s rocks tell scientists that Earth is about 4.5 billion years old. The rocks also provide evidence for how the land has changed many times since then.

Scientists believe the Grand Canyon formed 5.5 million years ago. Before that, nearly 2 billion years ago, mountains rose 10 kilometers (6 miles) above sea level where the Grand Canyon is today. This is as high as the Himalayas are.

Over time, the mountains wore down. The land became flat. Oceans covered it. And then a major disturbance changed the land. This disturbance pushed up the entire seabed to form a plateau. A plateau is an area of land that is relatively flat and significantly higher than the surrounding area.

In this lesson, students simulate the movement of tectonic plates to observe the cause-and-effect relationship between their movement and patterns in Earth’s features. Students use their observations about the cause-and-effect relationship between tectonic plates and Earth’s features to identify and explain patterns in the locations of mountain ranges, volcanoes, and earthquakes.