rocks Flashcards
what are rocks made from?
rocks are made up different minerals and materials
theses are held together by natural cement
there are many types of rocks with different mineral content, hardness and texture
how many types of rocks are there?
3
- Igneous
- Sedimentary
- Metamorphic
Types of igneous rocks
Granite Wicklow Mountain
Basalt Giants Causeway, Co. Antrim
Types of sedimentary rock
Limestone The Burren, Co Clare
Sandstone Galtee Mountains
Coal Arigna, Co Leitrim
Shale Arra Mountains
Types of metamorphic rock
Quartzite Croagh Patrick, Co Mayo Sugarloaf Mountain Co. Mayo
Marble Connemara, Kilkenny
How are igneous basalt rocks formed?
basalt is formed when lava from a volcano cools very quickly on the earths surface
what colour is basalt?
basalt is a black to a dark grey colour
Hoe are igneous granite rocks formed?
Granite is made when magma cools very slowly deep in the earths crust
what colour is granite?
it varies from pink, white, grey, black
What minerals are contained in granite?
Feldspar
Quartz
Mica
How are sedimentary rocks formed?
They are formed from the particles of dead plants and animals.
they were deposited on the sea bed and lakes and built up over time.
How were sedimentary limestone rocks formed?
Limestone is formed from the compression of the skeletons of small sea creatures fish and shells
What are the characteristics of limestone?
limestone is laid down in horizontal lines called strata
the vertical cracks are called joints
limestone is permeable - water can pass through limestone
limestone is easily weathered
fossils can be found in it
how are metamorphic rocks formed
metamorphic rocks are formed when rock that already exists, igneous or sedimentary are changed into new harder rocks by great heat or pressure
how is marble formed
marble is metamorphic rock formed by heat or pressure on limestone
