1. Mineral Resources

1. 1. Mineral Resources Environmental Studies - Unit 2 Lesson 1

2. Objectives • To know the structure of the Earth • To be able to list minerals that can be extracted from the Earth’s Crust. • To recap the rock cycle

3. The Earth

4. Resources from the Earth • There are a variety of natural resources taken from the Earth’s Crust including. • Fossil Fuels • Metals • Non Metal Materials

7. Rock Cycle

9. Sedimentary Processes

10. Alluvial / Placer Deposit

11. Evaporites

13. Biological Deposits • Chalks and limestone are formed from the Calcium carbonate shells of organims • Fossil fuels are formed from the build up of organic matter, compressed in anerobic conditions.

14. Chemical Precipitation Manganese Nodule Formed by the precipitation of the substance from sea water. This is a very slow process taking millions of years.

15. Metamorphic Rock

16. Intrusive Igneous - Batholiths

18. 2. Mineral Resources Environmental Studies – Unit 2 Lesson 2

19. What do you know about the following??? • Oil • Iron • Aluminium • Diamond

28. Gold Prices

29. Other Metals

30. BHP Share Price

31. Resources, reserves and Exploitation • Minerals are non-renewable resources because the amounts that exist are finite although most are very abundant. • Economically recoverable resources account for a tiny proportion of the total that exists. • The main limitations on mineral availability are the locations, chemical form and purity of the deposits, and the availability of technologies to exploit them. • Their exploitation is economically important but can cause environmental damage.

32. Lead Ore

33. Resources and Reserves • Resources include all the material which is theoretically available for exploitation. • This includes deposits that cannot be exploited now. eg too deep, low grade, unusable chemical form, prohibitive land use conflict • Reserves include that portion of the resource which can be exploited now, economically, using existing technology. The size of a resource is finite but the quantity included in the reserves can change. • eg the reserves will increase if there is an increase in market price or if new extraction technologies are developed. If market prices drop then reserves may decrease.

34. Sources and Demand Factors affecting the viability of exploiting mineral deposits • Extraction costs • Affected by depth, overburden quality, drainage problems, size of deposit. • Processing costs • The cost of extracting a metal depends upon the other elements with which it is combined. • eg aluminium is most abundant in clay but can only be economically extracted from bauxite • Purity • The financial cost, energy required and quantity of ore-bearing rock extracted all increase rapidly as ore purity decreases.

35. Factors affecting the viability of exploiting mineral deposits • Land conflicts Competing land uses may be considered more important or valuable than mining. E.g. urban areas, conservation of landscape or wildlife. Transport costs These are affected by the distance to market, the ease of bulk transport and the presence of a suitable existing transport infrastructure.

36. Factors affecting the viability of exploiting mineral deposits • Market economics The market demand and sale value of the minerals control the economic viability of exploiting a particular mineral deposit. The cut-off ore grade is the lowest ore purity that can be exploited economically.

37. Mineral Resources Environmental Studies – Unit 2 Lesson 3

38. The Environmental Impact of Mineral Exploitation Exploration, extraction and processing all cause significant environmental damage. A range of methods may be used to reduce these. www.goodquarry.com

39. Exploration • Marine seismic surveys affects whales. • Exploration on land causes vegetation loss. http://www.smh.com.au/news/whale-watch/blue-whales-face-seismic-upset-when-feeding/2008/01/08/1199554655598.html

40. Land take Minerals can only be exploited where they are found. This makes land use conflicts more likely as there is a limited choice of locations that can be exploited. Extraction may cause conflicts with existing land uses.

41. Habitat loss • The loss of the species where the mineral is to be extracted is unavoidable. • Removing the wildlife by capturing the animals and transplanting the plants to move them to unthreatened habitats has been attempted but is rarely completely successful. • Habitat restoration when mining has ended is often carried out.

42. Loss of Amenity Mining may cause aesthetic problems for local communities. This may be reduced by landscaping and tree planting.

43. Air Pollution Dust, reduced by water sprays. Noise, reduced by baffle mounds and restricted times for blasting.

44. Water Pollution • Turbid drainage water, reduced by sedimentation lagoons and filtration. • Toxic leachate, reduced by chemical treatment.

45. Spoil Disposal • Spoil instability can cause landslides or erosion. • It can be reduced by drainage, compaction and landscaping.

47. Transport nuisance • Mineral transportation can produce noise, fumes, dust and cause traffic accidents. • These can be reduced by water sprays and careful route choices.

48. Flooding can be caused by drainage water The risk can be reduced by containment in lagoons behind well-constructed dams with carefully timed releases.

49. Subsidence • This is caused by poor spoil compaction or undermining. • It can be reduced by compaction of spoil and leaving support pillars in deep mines

50. Turbid Drainage Water • Drainage water from mines or ore processing can smother aquatic plants and silt up rivers. • This can be reduced by building sedimentation lagoons.