Earth Layers
The Earth is composed of _________ layers.
four
The theory that Earth's plates moved in the past and are still moving today is known as _________
continental drift
An opening in the Earth's crust where ________ can escape is known as a volcano.
magma
lava
gasses
A sudden shaking in the Earth's crust is known as an ________
earthquake
The crust is broken up into ___________
plates
The __________ is the layer we live on.
crust
Pangea
Volcanoes that are currently erupting are known as _________ volcanoes.
active
Two plates sliding past each other is known as a _________ boundary.
transverse
S waves can only move through solids, so they stop when they hit the _________
outer core
Oceanic crust is ___________ than continental crust.
thinner
Divergent
_________ volcanoes are not expected to erupt again.
Extinct
The point of the actual rock rupture is known as the _________
focus
The strength of an earthquake is measured with the __________ numbers.
Richter Scale
The crust and upper layer of the mantle make up the ___________
lithosphere
The Atlantic Ocean is getting _______ due to continental drift.
larger
wider
Subduction zone volcanoes are created at the boundaries of two _________
plates
The point on the Earth's surface above the focus is known as the _________
epicenter
The Earth's core is made up of heavy metals such as __________
nickel and iron
The thickest layer of the Earth is the _________
mantle
When molten reaches the surface, it is called _______
lava
Rift zone volcanoes occur where two plates are _________
spreading apart
The first type of seismic waves to arrive on Earth's surface are __________
P waves
Primary waves
The mantle flows because of _____________
convection currents