Rocks

Igneous rocks

Think about it, do you know how Igneous rocks form? They are formed when the magma inside a volcano cools down and hardens quickly outside the Earth. There are two type of Igneous rocks that we know of, and they are the...

                                                                                  

Granite

Granite are coarse-grained(big visible grains)

Basalt

Basalt are fine-grained (very small grains)

Sedimentary rocks

Sendimentary rocks are formed when rocks break down into smaller pieces through weathering and erosion such as wind, rain, flowing river water. Small pieces of sediments (rocks+sand+clay+silt) get carried by wind and water into rivers. The sediments are then deposited and pile up in layers ,with the weight of more layers piling up, the sediments cement together and harden. And that is how Sedimentary rocks are formed!



Shale

Shale have distinctive layers and are fine-grained.

Conglomerate

Conglomerate have distinctive layers and are coarse-grained.

Limestone

Limestones are made up of hardened remains of animals and plants.

Metamorphic rocks

Metamorphic rocks are formed when Igneous and Sedimentary rocks comes into contact with intense heat and pressure. When plates move, one plate can slide underneath another plate, Metamorphism occurs; metamorphic rocks are then form inside the Earth. All Metamorphic rocks(Gneiss,Slate, Marble) have bands, foliated texture(minerals aligned in parallel layers) and are fine-grained.
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