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What Are Igneous Rocks?

igneous rocks objective to learn about

igneous rocks their types and formation

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the Earth's crust is made up of

different types of rocks the rocks which

make up the maximum volume of the

Earth's crust are called igneous rocks

the word igneous has been derived from

the Latin word Ignace which means fire

these rocks are associated with volcanic

eruptions

let's study more about igneous rocks and

how they are formed the liquid rock

matter that we see coming out from

volcanoes it is called magma

it is a hot liquid made of melted

minerals

when this magma reaches the Earth's

surface it is known as lava

the cooling and the solidification of

lava at the Earth's surface result in

the formation of extrusive igneous rocks

which are also known as volcanic rocks

due to rapid cooling their crystals are

fine-grained however some of the magma

can't come out and settles inside the

surface the magma cools slowly beneath

the Earth's surface as it is completely

surrounded by the soil and rock present

there the cooling and the solidification

of magma at a depth within the Earth's

crust result in the formation of rocks

having large crystals known as intrusive

igneous rocks

so we have learned that igneous rocks

are of two types extrusive igneous rocks

and intrusive igneous rocks it is

interesting to know that igneous rocks

were the first to be formed and are also

known as primary rocks pumice and

obsidian are extrusive igneous rocks

pumice is used in making lightweight

concrete an obsidian is used in

ornaments

granite and diorite are intrusive

igneous rocks both they used as building

material to summarize igneous rocks are

of two types extrusive igneous rocks and

intrusive igneous rocks

the cooling and the solidification of

lava at the Earth's surface result in

the formation of extrusive igneous rocks

they are also known as volcanic rocks

the cooling and the solidification of

magma at a depth within the Earth's

crust result in the formation of

intrusive igneous rocks

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