Transcript Rocks - Ramsgrange Community School

Rocks
Rocks are classified…
…...According to formation
– Igneous – volcanic material
– Sedimentary – compressed remains
– Metamorphic – changed by heat/pressure
Igneous Rocks
• Formed when magma (lava) cools and
solidifies. Most common Igneous rocks
include Granite and Basalt.
Granite
Basalt
Igneous
Granite
• Hard, coarse, multi
coloured
• Cooled magma inside
earth
• Wicklow Mtns
Basalt
• Heavy, black
• Lava cooled on
surface
• Giants Causeway
Granite –
Mount
Rushmore
Basalt –
Giant’s
Causeway
Sedimentary Rocks
• Formed when the remains of dead sea
creatures and plants build up in layers.
They get compressed and cemented
together over time. Most common include
Limestone and Sandstone.
Limestone
Sandstone
Sedimentary
Sandstone
• Coarse, brown, red
• Compressed sand
grains
• Magillicuddy Reeks
Limestone
• White/grey
• Compressed fish
remains/skeletons
• The Burren
Limestone
• Strata (layers)
• Horizontal bedding
planes
• Vertical joints
• Permeable (water
seeps through)
• Easily weathered
• Contains fossils
Metamorphic Rocks
• Formed when either Igneous or
Sedimentary rock is put under great heat
or pressure.
Marble
Quartzite
Metamorphic
Marble
• Hard, crystal
• White, green, red,
black
• Limestone changes to
marble through heat
or pressure
• Connemara
Key Words
• Strata: a horizontal layer in rock or soil,
sometimes called bedding planes.
• Joint: a vertical crack in rock.
• Permeable: allows water to pass through.
• Porous: holds water and allows it to pass
through.
• Fossil: the preserved remains of a plant or
animal.
Extraction industry
• Shaft mining – underground, for lead and
coal
• Offshore drilling – for oil + gas
• Open cast mining + Quarrying – surface,
for stone, sand, gravel and peat