Inside Earth:
Chapter 1: Plate Tectonics
Section 1: Earths Interior
Vocabulary:
Geologists: scientists that study the Earth; rock
Rock: the material that forms Earth’s hard surface
Geology: the study of planet Earth
Constructive Forces: forces that build up mountains and landmasses
Destructive Forces: forces that destroy mountains and other features of land
Continents: the seven great landmasses surrounded by oceans (Asia, Europe, North America,
South America, Antarctica, Africa, Australia)
Seismic Waves: vibration that travels through Earth, carrying the energy released during an
earthquake
Pressure: amount of force pushing on a surface (huge amount of pressure on the core)
Important Facts:
 Geologists study the processes that create Earth’s features and search for clues about
Earth’s history
 Geologists have to make predictions about what the Earth’s interior is made of by
making indirect observations of seismic waves
 The Earth has a magnetic force that is caused by the inner core spinning within the
outer
 Earth is made up of 3 main layers
1. Crust: Layer of rock that forms Earth’s outer skin
 Includes soil and water
 5-40km thick
 Oceanic Crust: crust beneath the ocean
o Thin layer of crust
o Made of dense rock such as basalt
o Made of- Basalt: dark dense rock with a fine texture

Continental Crust: crust that forms the continents
o Thicker layer of crust
o Made of less dense rocks such as granite
o Made of- Granite: rock that has larger crystals basalt
and is not as dense; usually light in color
2. Mantle: a layer of hot rock under the Earth’s crust
 Lithosphere: a rigid layer made up of the uppermost part of the
mantle and the crust; about 100km thick- (tectonic plates)
 Under the Lithosphere is a layer of hot rock
 Temperature and pressure in the mantle increase with depth
 Asthenosphere: thick, soft material that flows in the mantle;
about 3,000km thick; moves in a convection current
3. Core: innermost layer of Earth; consists of 2 parts
 Outer Core
o layer of molten metal that surround the inner core
o Behaves like a thick liquid
o Is under enormous pressure
 Inner Core
o Dense ball of solid metal
o Extreme pressure makes it a solid