Rocks Flashcards
Name two igneous rocks
Granite, basalt
Name three types of rock
Igneous, sedimentary, metamorphic.
How is granite formed?
Granite is made when magma forces it’s way into the crust. It cools very slowly over millions of years to form large crystals. The rock comes to the surface when all the rocks above are worn away.
What colour can granite be?
It can be black to greyish colours as well as pink
What is granite used for?
Monuments, countertops
What type of rock is quartzite?
Metamorphic
Name two metamorphic rocks.
Quartzite and marble
How is marble formed?
When molten magma forces it’s way into limestone it becomes under great heat and pressure. This changes the make up of the rock and changes it to marble
What colour is marble? (Pure)
White
What is marble used for?
Fireplaces ornaments gravestones
How is basalt made?
Basalt is formed when lava spreads out across the earths surface and cools very quickly because it is exposed to the air. It can result in tiny crystals forming in the rock that can’t be seen by the naked eye.
What colour is basalt?
Basalt varies in colour from black to light grey.
Name two sedimentary rocks.
Limestone, sandstone
How Is limestone formed?
Limestone is formed on the beds of shallow warm seas from the remains and skeletons of tiny sea creatures, fish and shells. The different particles are cemented together after they pile up over millions of years
What colour is limestone
Limestone varies in colour from white to dark grey
What is limestone used for?
It’s the raw material for cement
Monuments
Is limestone permeable? True/false
True
How is sandstone formed.
Sandstone is formed when sand is deposited on the beds of lakes or seas as well as deserts. The sand builds up over time and is then compressed and cemented together
What colour is sandstone
Brown/red colour
How are igneous rocks formed
Igneous rocks are formed due to volcanic activity. They are formed when lava or magma cools and solidifies either on land or in the crust
How are metamorphic rocks formed
Metamorphic rocks are when other rocks change in some shape or form by great heat and pressure. These rocks are either igneous or sedimentary before they change.
How are sedimentary rocks formed
Sedimentary rocks are formed from the remains of small animals, plants or other rocks. They are made when lots of different pieces fit together and pile up over millions of years on the beds of seas lakes or on land. These particles are then compressed and cemented together.
How is quartzite formed
Quartzite is formed when magma comes into contact with sandstone deep in the earth’s crust.
What colour is quartzite
Grey/white
What can rocks be used for today in our economy
Ground up rock can be used in agriculture as part of fertiliser
Construction requires blocks and cement which is made of rocks, limestone
Making of headstones and ornaments
