3 TYPES OF ROCKS

WHAT IS A ROCK

• A rock is a combination of one or more minerals of organic matter

TEXTURE AND CLASSIFACATION

• A rock's texture is the size, shape, and positions of the grains that make up a rock
• A rock is classified by mineral composition and by texture

TYPES

• Igneous
• Metamorphic
• Sedimentary

IGNEOUS

• Igneous rocks form from the Earth's mantle, or from lava on the surface of the Earth

TWO KINDS OF IGNEOUS ROCKS

• Intrusive
• They form inside the Earth's mantle (generally coarse-grained) an example is granite
• Extrusive
• They form on Earth's crust and they cool fast (generally fine-grained)an example is obsidian

SEDEMENTARY

• They form by extreme pressure compressing small rocks and minerals down

TYPES OF SEDIMENTARY ROCKS

• Clastic
• They are made up of rock fragments and example is shale
• Chemical
• They are made up from precipitates an example is limestone
• Organic
• They are made up from once living material an example is coal

METAMORPHIC ROCKS

• They form from changed rock; made from preexisting heat, pressure and chemical reactions

TYPES OF METAMORPHIC ROCKS

• Foilated
• They are formed when mineral crystals are arranged in bands an example is schist
• Non-foilated
• These are formed when the minerals are not arranged in bands an example is Quartz