Earth’s Spooky Layers
Which is the thinnest layer of Earth that we live on?
The Crust
Which Extrusive igneous rock forms when lava cools quickly and has a glassy appearance?
Obsidian
What determines the size of crystals in igneous rocks?
The cooling rate of magma or lava
Is granite an intrusive or extrusive rock?
Intrusive
What happens to temperature and pressure as you go deeper into Earth's layers?
Both temperature and pressure increase.
What layer is made of hot, molten rock that flows slowly?
The Mantle
What is the difference between magma and lava?
Magma is below Earth's surface; lava is above Earth's surface.
True or False: Faster cooling of lava results in larger crystals.
False
What do we call rocks that form from lava cooling quickly on Earth’s surface?
Extrusive igneous rocks
What is the rigid outer layer of Earth that includes the crust and upper mantle?
The Lithosphere
Which layer of Earth is the hottest and composed mostly of iron and nickel?
The Inner Core
Which dark, fine-grained Extrusive rock forms from lava cooling at the surface?
Basalt
Which type of igneous rock typically has small crystals due to fast cooling?
Extrusive igneous rock
What type of igneous rock is oceanic crust made of?
Basalt
What layer lies directly beneath the lithosphere and is semi-solid?
The Asthenosphere
Where do convection currents that move tectonic plates occur?
In the lower mantle
What type of igneous rock has large crystals because it cools slowly?
Intrusive igneous rock
Which example of intrusive igneous rock has larger crystals due to slow cooling below Earth's surface?
Granite
Which type of igneous rock is more likely to have a coarse-grained texture, intrusive or extrusive?
Intrusive
What causes Earth’s magnetic field?
The movement of molten iron in the outer core
The Earth is divided into layers based on their densities. What are the compositional layers?
Crust, Mantle, Core
Do igneous rocks react with hydrochloric acid?
No
Name one possible indication that a rock is igneous.
Presence of crystals
What type of igneous rock is continental crust made of?
Granite
What causes the movement of tectonic plates?
Convection currents in the lower mantle