1. WHAT ARE IGNEOUS, METAMORPHIC AND SEDIMENTARY ROCKS?

2. What is magma? (again)  A hot mix of molten rock, gases and minerals  Common Earth elements like O, Si, Al, Fe, Mg, Ca, K and Na are found in magma  SILICA (SiO 2 ) is the most abundant material in magma.  Silica is often found in sand and quartz  Silica content affects the melting temperature of magma. (which influences viscosity)

4. What is magma? (again)  Magma experiences partial melting because of its heterogeneous composition. ( what does this mean? )

5. What is magma? (again)  Fractional Crystallization: Different minerals within magma cool and crystallize under different conditions  Crystallization and partial melting have a reverse relationship.  The first minerals to crystallize are the last minerals to melt

6. 1. Igneous rocks  Igneous rocks form from the crystallization (deposition) of magma  Extrusive igneous rock is typically of a fine grain and is formed during quick cooling  Intrusive igneous rock is typically of a coarse grain and is formed during slow cooling periods

8. Bowen’s Reaction Series  N. L. Bowen, a Canadian geologist modelled a pattern of mineral crystallization  As temperatures begin to cool, some calcium-rich minerals undergo a continuous change over a long temperature interval and become sodium-rich  Some iron-rich minerals undergo discontinuous change. These minerals undergo abrupt changes in crystallization.

9. Bowen’s reaction series: (p. 114) Samples: 35, 33, 34, 30, 32, 22 or 23

10. Bowen’s reaction series: (p. 114)

12. Bowen’s reaction series  As more and more materials crystallize out of cooling magma, the remaining rock becomes concentrated with silica.  Quartz is the last mineral to crystallize out (mainly silica)

15. IF ROCKS CHANGE THEIR CRYSTALLINE STRUCTURE AND CHEMICAL COMPOSITION AS THEY COOL, WHY DOES OLIVINE EXIST FOR US TO SEE? The simple answer is crystal separation

16. Bowen’s reaction series: Figure 5-6 (p. 104)

17. Classifying Igneous Rocks  Mafic rock has low silica content and are rich in iron. They contain plagioclase, biotite, amphibole, pyroxene, and olivine; EX. Gabbro  Felsic rock have high silica content and contain quartz and feldspars  Ultramafic rock contains super-low silica and super high iron. Sample: 38

18. Classifying Igneous Rocks  Differences between similar samples such as size, shape, grain size and texture may be described by cooling rates of magma  Mineral grains, rather than rock shape, are used for identification. (why?)  Porphyritic texture describes well-formed crystals surrounded by fine grained crystals of the same or differing material

21. Igneous Rock for Industry  Interlocking grains give strength  Some mineral crystals are naturally resistant to weathering  Granite composition may be aesthetically pleasing

23. Igneous ‘Veins’  Some metallic elements like gold, silver, lead and copper are not a part of common minerals and behave in a similar way to silica.  They are the last substances to precipitate out of magma during cooling

26. Minerals Veins  Large-grain minerals containing rare elements like lithium and beryllium  Type of ultramafic rock (low silica, high elemental metal)  Diamonds form in kimberlite  MIR MINE PegmatitesKimberlites

28. Read section 5.1 on pages 112-117 and answer questions: 1-6 Read section 5.2 on pages 118 – 123 and answer questions 1-4 Read section 5.1 on pages 112-117 and answer questions: 1-6 Read section 5.2 on pages 118 – 123 and answer questions 1-4

29. 2. Sedimentary Rocks  Sediment refers to material that is broken down through weathering and transported by erosion, ice and gravity  These fragments of material stick together to form sedimentary rock  Materials within sedimentary rock vary in their resistance to weathering which produces clastic rock (‘broken’ rock)

31. Sediments Size Very small particles Very large particles ClaySiltSandGravel PebbleCobbleBoulder

37. Deposition and Lithification  Larger materials deposit first in fluids  Transport by ice does not discriminate between particle sizes

38. Lithification  Pressure from overlying material force sedimentary rock to compact.  Clay and silt do not allow much space for water, but sand and larger particles do.  Water and materials travel through sedimentary rock into the Earth where temperatures increase by 30˚C every kilometer below the surface  At around 4 kilometers below the Earth’s surface cementation may begin to occur

39. Lithification occurs through Cementation 1. Unique minerals like Calcite or iron oxide grow in-between sediment grains 2. Existing mineral grains grow larger as more of the same mineral becomes available

41. Bedding  Bedding refers to the horizontal layering of sedimentary rock through erosion and grain size  Graded-bedding refers to bedding that contains coarse and heavy layers near the bottom layers  Cross-bedding refers to layers of sediment that are inclined and represent sedimentary layers that move horizontally along a surface through the action of wind or water

47. Clastics: Coarse grain  Particles travelling as bed load become rounded and eventually become conglomerate (rounded and coarse grained clastic)  Angular coarse grained clastic is called breccia Sample: 54

54. Clastics: Medium Grain  These rock forms usually come from rivers and streams and form sandstone  Stratification tells scientists the direction of fluid movement  High porosity allows water to move through sandstone and can allow oil, natural gas and groundwater reservoirs to form Sample: 55

55. Clastics: Fine Grain  Very low porosity that does not allow for movement of fluids  Forms shale Sample: 56

57. Sedimentary Rock created through Chemical Process  Chemical  Minerals that precipitate out of solution during evaporation are called evaporites  Examples; Halite (salt), calcite (calcium carbonate aka old chalk) and gypsum (calcium sulfate) Samples: 63, 64

58. Sedimentary Rock created through Biological Process  Organic  Rock formed from the remains of living things  Examples; limestone from organic sea shells and bone Coal from thick layers of plant material

59. Read section 6.1 on pages 134 - 140 and answer questions: 3-6 Read section 6.2 on pages 141 – 144 and answer questions 1-7 Read section 6.1 on pages 134 - 140 and answer questions: 3-6 Read section 6.2 on pages 141 – 144 and answer questions 1-7