Geology: Mineral, Rock, and Energy Resources

1. Geology 12 Presents Hand out note helper WS 7.2A

3. This is the money!!! $$$$$$$$$$$$$$$ • Number two industry in B.C. • Average mining job >$84,000/year • Future and current resource shortages has created a huge demand for geologists.

4. Mineral, Rock and Energy Resources • Terminology • 1. Reserves: quantity of a given material (i.e. gold) that has been found and can be mined economically with existing technology • 2. Resources: reserves + deposits that are known but can’t be exploited given current prices and technology (i.e. Gold at submerged spreading ridges)

5. 3. Non-renewable Resource: not being produced at present (i.e. iron ore) or is being consumed faster than it is being produced (i.e. oil & gas) • 4. Renewable Resource: can be replenished as fast as it is used (i.e. wood) or is used without actual depletion of supply (i.e. wind)

6. 5. Ore: rock in which valuable metal occurs in sufficient concentration to make it economical to mine. • It is dependent on: • a) price of ore/metal • b) concentration of metal in ore • c) size of deposit • d) geographic location (accessibility, political factor, ownership) • e) environmental threat

7. Economic Geology: • Is where most jobs are for geologists • is usually divided into 2 fields: A: hardrock: metal ore exploration (igneous & metamorphic) and B: softrock: oil, natural gas & coal (sedimentary) Oil & gas = fossil fuels Coal Metals: ex: Copper, lead, zinc, gold, silver, uranium, platinum

11. A: Hardrock = Metals and Minerals • How the metal ores form (4 ways) • 1. Magmatic Deposits: result of magma activity • a) Pegmatites (crystals up to 10m long!) crystalize from residual fluids of solidifying magma leaving many trace rare/trace elements such as Li ( ), B ( ), Be ( ), and U ( ). lithium beryllium boron uranium

12. a) Pegmatites Beryl

13. Boron

14. b) Fractional Crystalization: chromite & magnetite crystals form & settle out. Caused by differences in the density of minerals

15. b)

16. Draw this

18. c) Xenoliths of diamonds in volcanic pipes

19. c) Xenoliths of diamonds

20. Xenolith

26. 2. Hydrothermal Ores (hot water): hot magma fluids escape through pores & cracks in the country rock carrying dissolved gases, salts & metals, PLUS, leaching additional metals from the rocks they pass. Eventually the fluids cool depositing their dissolved minerals. • Water can come from groundwater as well. • Occur at: • a) near intrusions

27. Country rock Qtz & metals fluid Large qtz crystals Draw this veins Cooling magma

28. 2. Hydrothermal Ores

30. Chalcopyrite copper = wiring Uses:

31. Sphalerite zinc= galvanizing

32. Galena lead = car batteries

33. Gold = electronics, jewellery

34. Silver = electronic, jewellery

35. Platinum = catalytic converters on cars

36. Torbernite uranium = nuclear reactors

37. Form: copper, zinc, lead, silver, platinum, uranium, etc. • Often as sulfides such as: • Sphalerite = ZnS = zinc ore • Galena = PbS = lead ore • Chalcopyrite = CuFeS2 = copper ore

38. Occur at: • b) spreading centres (submarine “black smokers”) Cold ocean Hot, sulfide-rich water Draw this Descending sea water Mineral ore High heat flow Hot magma

39. Sinking sea water is warmed, dissolves metals in sea floor rocks, then rises cooling and reacting with unaltered, cold sea water to deposit minerals • Ex: off W. coast of Vancouver Island.

41. Victoria

44. 3. Sedimentary Deposits • a) Chemical Deposits: • i) oxidation: iron oxides precipitated out of sea water when early life produced O2 to form layered beds of iron ore (hematite). • ii) evaporation: during early stages of continental rifting, shallow seas with poor circulation became supper salty causing minerals to precipitate out • Ex: rock salt, gypsum, potash

45. Hematite iron steel

47. Early rift = Death Valley

48. Death Valley salt flats

49. Dead Sea

50. Gypsum gyprock CaSO4 . 2H2O