Chapter 3 & 5: The Dynamic Earth & Natural Hazards

What are the four environmental spheres?

Lithosphere, biosphere, hydrosphere, and atmosphere.

What is the lithosphere?

The solid outer layer of Earth made of rocks and soil.

What is the biosphere?

All living organisms on Earth.

What is the hydrosphere?

All of Earth's water.

What is the atmosphere?

The layer of gases surrounding Earth.

Why is Earth different from most other planets?

It has liquid water, which makes life possible.

What is plate tectonics?

The theory that Earth's lithosphere is divided into moving tectonic plates.

What does plate tectonics explain?

Continental movement, mountain building, seafloor creation and destruction, volcanoes, and earthquakes.

Who proposed the idea of continental movement?

Alfred Wegener.

How fast do tectonic plates move?

About 0.8–12 inches (2–30 cm) per year.

Where do most earthquakes and volcanoes occur?

Along tectonic plate boundaries.

What causes tectonic plates to move?

Convection currents in Earth's hot, molten mantle.

What are the three types of plate boundaries? (on exam)

Divergent, convergent, and transform.

What happens at a divergent boundary?

Plates move apart and new crust can form.

What happens at a convergent boundary?

Plates move toward each other and collide.

What happens at a transform boundary?

Plates slide past each other.

What is a subduction zone?

An area where one tectonic plate moves beneath another plate.

What is an example of a divergent boundary?

The Mid-Atlantic Ridge.

What is an example of a transform boundary?

The San Andreas Fault.

What happens when two continental plates converge?

They can form large mountain ranges.

What is an example of continental-continental convergence?

The Himalayas.

What can happen when an oceanic plate converges with a continental plate?

The oceanic plate can subduct beneath the continental plate, causing volcanoes and mountains.

What are hot spots?

Areas where heat and magma rise from Earth's interior through a tectonic plate.

What are examples of hot spots?

Hawaii (oceanic) and Yellowstone (continental).

What are minerals?

Inorganic solids with a specific structure and composition.

What are the three major types of rocks?

Igneous, sedimentary, and metamorphic.

What is the rock cycle?

The process through which rocks are formed, broken down, and transformed into different types of rocks.

How does plate tectonics affect the rock cycle?

Plate tectonics drives geological processes that create, destroy, and recycle rocks.

Why are earthquakes and volcanoes considered natural hazards?

They are natural events that can cause damage to humans and the environment.

How can humans reduce the effects of natural hazards?

Through prediction, preparation, and mitigation.