Mining and Quarrying
What is mining and quarrying?
Man has been mining since the early development of society e.g. Stone, Bronze and Iron ages. Virtually every manufactured item contains mineral products which have been mined or quarried.
Quarrying is normally associated with the extraction of rock using opencast techniques and leaving large holes in the ground.
1km of motorway requires 125,000 tonnes of crushed stone.
Mining can be opencast but more often involves digging tunnels below ground. Normally topsoil and underlying bedrock is removed (known as overburden) and stacked on spoil heaps nearby. Rock from tunnelling is added to this.
Mined compounds are normally classified into four groups:
- Metals (copper and aluminium)
- Industrial minerals (lime, soda ash)
- Construction materials (sand, gravel)
- Energy materials (coal, uranium)
Global economic aspects
- As the human population grows, there is a greater demand for minerals.
- Since 1900, there has been a thirteen-fold increase in demand.
- In the 70’s there were concerns that certain minerals would run-out.
- Discovery of new resources and an increase in recycling has largely prevented the total depletion of many mineral resources. Some minerals, if recycled, could possibly be thought of as ‘renewable resources’?
- Many countries export minerals and this is an important source of income.
In 1556, Georgius Agricola noted the devastating effects of mining: