Chapter 3: Earth’s Structure, Earthquakes, Volcanoes, and Rocks

Earth’s Structure

100

 The study of the Earth and its structure. 

GEOLOGY

200

 This is the outermost, solid layer of the Earth where we live.

CRUST

300

This boundary marks the transition between the crust and the mantle.

Moho

400

This specific part of the core is liquid, creating Earth's magnetic field. 

OUTER CORE

500

The Earth’s core is primarily composed of these two metallic elements.

Iron & Nickel

Earthquakes

100

Any trembling or shaking of the earth’s crust. 

Earthquake

200

Scientist who compares the magnitude of earthquakes from different years to understand their impact.

seismologist

300

Scientists use this instrument to detect and record the vibrations of an earthquake.

Seismograph

400

The sudden movement of the Pacific plate under the ocean floor also created monstrous waves

Tsunami

500

This is the point on the Earth's surface directly above where an earthquake starts.

Epicenter

Volcanoes

100

The molten rock that has reached the earth’s surface

Lava

200

This famous "belt" in the Pacific Ocean is where the majority of the world’s active volcanoes are located.

Ring of Fire

300

A hole in a volcanic region from which hot gases and vapors come out

Fumaroles

400

Refers to rock fragments, such as volcanic ash, lapilli, and volcanic bombs, that are formed when lava solidifies instantly

TEPHRA

500

Differentiate: Mountain vs Volcano

• A mountain is formed due to various geological processes like movement and opposition of tectonic plates
• A volcano is formed around a vent that allows magma to reach the surface of the earth. It all has to do with plate tectonics.

Classification of Volcanoes

100

Its eruption is noisy but usually quite mild.

STROMBOLIAN ERUPTION

200

Relatively small, coned-shaped volcanoes formed mostly of tephra and are quickly eroded.

CINDER CONE VOLCANOES

300

Also known as stratovolcanoes, these are tall, cone-shaped mountains composed of alternating layers of lava and ash.

Composite

400

Differentiate active, dormant, and extinct volcano.

1. ACTIVE - one that has erupted recently or is considered likely to erupt in the near future2. DORMANT - a volcano that has erupted many years ago and is now inactive, but which may erupt again
3. EXTINCT - volcanoes that have not erupted in recorded history or are unlikely to erupt again

500

The volcano expels hot clouds of gas and dust high into the atmosphere forming ash clouds

PLINIAN ERUPTION

Rocks

100

These rocks are formed when magma or lava cools and hardens.

Igneous rocks

200

These rocks are formed from pieces of sand, shells, and pebbles that are pressed together over a long time.

Sedimentary rocks

300

This type of rock is formed when existing rocks are subjected to intense heat and pressure without melting.

Metamorphic

400

 Natural acids from the rain or certain plants cause the rock to break apart

Chemical Weathering

500

A process that causes rocks to gradually break and crumble into smaller pieces will result in the formation of soil

WEATHERING