Ch. 5 Rocks

What are ingeous rocks?

Rocks that formed when magma is cooled

What are sedimentary rocks?

Rocks that are formed when sediments are compressed by layers of other sediment and fossils

What are metaphoric rocks?

Rocks that are formed when igneous or sedimentary rock are changed by the heat and pressure of molten lava

How is granite formed? Give a use and a location.

Granite is a grey, speckled igneous rock that forms when magma cools slowly beneath the Earth’s surface, allowing large crystals to develop. It is hard with a rough texture and over 400 million years old in Ireland. Granite is used in buildings, kerbs, and kitchen countertops. It is found in the Wicklow and Mourne Mountains, as well as in Donegal and Connemara.

How is limestone formed? Give a use and a location

Limestone is a sedimentary rock formed 350 million years ago from the remains of sea creatures, sand, and silt that compacted into layers. Fossils are often found in it. It ranges in colour from white to black and can be smooth or rough. Limestone is soft and can be dissolved by weak acid. It is used in road construction and as a building material. Limestone is found across most of Ireland e.g. the Burren, Co. Clare.

How is marble formed? Give a use and an example.

Marble is a metamorphic rock formed when limestone is changed by heat from magma, creating crystals. It is smooth, dense, cold to touch, and hard but brittle. Marble ranges from white to black, often with coloured veins from minerals like iron or manganese. It is used in sculpture, fireplaces, countertops, and floor tiles. Green marble is found in Connemara.

Give 3 points on rock exploitation.

•Oil and gas are extracted by drilling. Oil provides us with fuels and plastics.

• Rocks provide us with building materials, ores that contain metals, and gemstones.
  These are extracted using either opencast mining or shaft mining.

• Coal also is extracted using opencast mining or shaft mining.

Describe the environmental, economic and social impact of rock exploitation.

Rock exploitation provides valuable natural resources used in everyday life. It creates jobs, supports settlements, and brings income to regions. Extracted materials like lead and zinc also support other industries. However, it can damage the landscape, leaving pits or waste heaps, and activities like oil drilling risk harmful spills. Companies are expected to improve methods to reduce environmental impact.