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rocks and minerals-131013154238-phpapp01.ppt
This document provides information about minerals and rocks. It defines minerals as solid, naturally occurring substances that have a definite chemical composition and internal structure. Minerals can be identified based on their physical properties like color, luster, hardness, cleavage, and crystal shape. Rocks are composed of two or more minerals and form through igneous, sedimentary, and metamorphic processes. Igneous rocks form from the cooling of magma, sedimentary rocks form through the compaction and cementation of sediments, and metamorphic rocks form under heat and pressure.
rocks and minerals-131013154238-phpapp01.ppt
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- 2. Minerals can be identifiedby their chemical and physical properties.
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- 4. What does thatmean?!?!?! --Not a gas or a liquid --Has a definite shape and volume QUESTION? Is oil a mineral?? Answer… No, because it is a liquid.
- 5. What does thatmean?!?!?! --Not man-made
- 6. What does thatmean?!?!?! --Not formed from living things or the remains of living things --NON-LIVING!! EXAMPLES 1. Coal is NOT a mineral because it comes from plants. 2. Amber is NOT a mineral because it comes from tree sap. 3. A pearl is NOT a mineral because it comes from oysters.
- 7. What does thatmean?!?!?! --The elements that make up the minerals are combined in definite proportions --Chemical formula can be found on page 16 of ESRT. EXAMPLES -Gold (Au) -Pyrite (FeS²) -Graphite (C) -Diamond (C)
- 8. What does thatmean?!?!?! --Atoms are arranged in a repeating pattern --Each mineral has a different INTERNAL ARRANGEMENT OF ATOMS that gives it distinct physical and chemical properties
- 9. What does that mean?!?!?! QUESTION Howdoes the mineral graphite, which is soft have the same chemical formula as diamond, which is the hardest mineral in the world? ANSWER Because their internal arrangement of atoms are different
- 10. How are Minerals Identified?? Fill inthe spiders legs as we go!!
- 11. Minerals can be identifiedby their chemical and physical properties.
- 12. How are MineralsIdentified?? --Least useful for identification --One mineral can come in many colors EXAMPLE: --Hematite: Comes in black, red and brown
- 13. How are MineralsIdentified?? 1. Some minerals are always the same color 2. Some minerals can have many colors Smoky Quartz Rose Quartz Quartz Sulfur
- 14. Colors can varyas a result of… A. Chemical Impurities– Cobalt compounds tend to be pink, purple, or blue Manganese—tends to produce pink colors
- 15. Colors can varyas a result of… B. Oxidation—exposure to air and water changing the color of the mineral. Ex. Rust --Iron is the dominant coloring agent in rocks and soils
- 16. How are MineralsIdentified?? --the color of a mineral when it is finely powdered --determined by rubbing the mineral on a piece of tile Hematite has a reddish-brown streak.
- 17. How are MineralsIdentified?? --describes how a mineral appears to reflect light There are 2 categories in which a minerals luster can fall… Metallic OR Non-Metallic
- 18. How are MineralsIdentified?? A. Metallic– reflects light like metal (shiny) Galena Graphite Pyrite
- 19. How are MineralsIdentified?? B. Non-Metallic—any mineral which DOES NOT exhibit shiny metallic characteristics Ex. Quartz
- 20. Metallic or Non-Metallic?? Non-Metallic Mica Pearlyluster Metallic Magnetite
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- 22. How are MineralsIdentified?? --Resistance of a mineral to being scratched --Moh’s Hardness Scale—compares the hardness of the mineral to 10 reference minerals.
- 23. How is HardnessDetermined?? Softest Hardest The scale consists of number 1 through 10; 1 being the softest and 10 being the hardest. Each number represents a different mineral- each harder than the previous. The 10 minerals are to the left.
- 24. How is HardnessDetermined?? Several common household items have a fixed hardness, and can be used to test for hardness. -Fingernail = 2.5 -Copper penny = 3-3.5 -Nail = 4.5 -Knife blade = 5.5 -Glass = 5.5 -Steel file = 6.5 -Streak plate = 7
- 25. What Determines Hardness? --Hardnessis determined by a minerals internal arrangement of atoms. Ex. Diamond vs. Graphite -Diamond has hardness of 10 and graphite is ranked between 1 and 2. Diamond is about 40 times harder than graphite due to the way the atoms are arranged. --Hardness is the best property to use to identify a mineral.
- 26. How are MineralsIdentified?? Cleavage—when a mineral breaks along a flat, smooth surface
- 27. Examples of Mineralsthat show Cleavage Mica exhibits basal cleavage. Galena exhibits cubic cleavage.
- 29. What Determines Cleavageand Hardness? A minerals internal arrangement of atoms!!
- 30. How are MineralsIdentified?? Fracture—When a mineral breaks along irregular rough surfaces. EX. Quartz
- 31. How are MineralsIdentified?? --The amount of matter in a given space (mass/volume) Depends on… -kind of atoms which make up the mineral -how the atoms are arranged in the crystal lattice
- 32. How are MineralsIdentified?? Crystal Shape --Minerals have a characteristic crystal shape resulting from the atomic packing of the atoms when the mineral is forming
- 33. How are MineralsIdentified?? -Magnetism (Magnetite) -Glowing under ultraviolet light (Fluorite) -Salty taste (Halite) -Smell (Sulfur) -Reaction to HCl (Calcite)
- 34. Rocks Parent Material for allRock?? Magma!!
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- 36. How are rocks formed? Rocksare classified by their process of formation.
- 37. The Rock Cycle •The Rock Cycle describes the continually changing structure of rocks. Sedimentary Rocks Igneous Rocks Metamorphic Rocks Magma Sediments
- 38. Texture and GrainSize • Texture is described based on grain size, grain shape, and grain pattern. • Most rocks are made up of tiny particles of minerals or other rocks, which are called grains. • A rock’s grains give it its texture
- 39. Distribution of Rocksin the U.S.
- 40. Rocks Made oftwo or more different minerals that have been: • cemented together (Sedimentary) • squeezed and heated together (Metamorphic) • melted and cooled together (Igneous)
- 41. Igneous Sedimentary Metamorphic sediments and minerals arecompacted and cemented With dissolved minerals Clastic – pieces of other rocks Cemented into rock Chemical – Evaporites From seawater Organic/Bioclastic Remains of plants Or animals which Are transformed Into rock ROCKS
- 42. Igneous Rock • Igneousrock forms when magma or lava COOLS Solidifies Crystallizes hardens
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- 44. TEXTURE Intrusive or Plutonic Extrusive or Volcanic CoarseGrained large crystals Non-Vesicular (no gas bubbles) Magma Underground Slow cooling Fine Grained (small crystals) Glassy Gas Pockets (vesicular) LAVA Above ground FAST cooling
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- 46. Igneous Rock Mineral Composition FELSIC Lowdensity MAFIC High Density Rich in Aluminum Rich in IRON & Magnesium Light Colored Rocks Called Dark Colored Rocks Called
- 47. Sedimentary Rocks Form when Minerals Clastic And Arecemented together The 3 types of sedimentary rock are SEDIMENTS Chemical Organic
- 48. •Through the processof , rock is loosened and carried away with wind and water by . The sediment then settles out of the wind and water during deposition. The sediment begins to settle out and form . Origins of Sedimentary Rock – Draw an arrow from “CLASTIC” weathering erosion layers compaction Cementation As the layers stack up, they become heavier until the weight squeezes the layers together during . Dissolved minerals act as glue in a process known as .
- 49. • This isa sample of sandstone, a sedimentary rock that formed from sand grains.
- 50. Chemical • Formed whenminerals dissolved in water, precipitate out and form crystals on the sea floor – Includes evaporites.
- 52. Organic (bioclastic) –rocks formed from the remains of plants and/or animals that undergoes a transformation into rock.
- 53. • This isa sample of limestone, a sedimentary rock made of calcium carbonate that formed under water indirectly from the remains of tiny marine organisms.
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- 55. Metamorphic Rocks Conditions thatcause rocks to undergo metamorphism include: • Deep burial and pressure or hot contact zones • Metamorphic rocks are often found in mountainous regions You’ll have to add this to your notes on page 8
- 56. Heat Pressure Chemical due to Contact Metamorphicrocks are characterized by: • Increased DENSITY • NEW Minerals • BANDING Metamorphic Rocks – formed when a rock is changed by
- 57. Metamorphic Rocks are classifiedby the arrangement of their: MINERALS
- 58. Into two typesof metamorphic rocks called: Non - Foliated Foliated and Where the minerals grains are Where the minerals grains are Not aligned and appear MASSIVE Squeezed and curved or folded
- 59. Foliated (think FOLD) Mica Schist Gneiss IncreasedHEAT and PRESSURE
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- 62. • Increasing metamorphicchange occurs with increasing temperatures and pressures. • If the melting point is reached, the change is no longer metamorphic, and igneous rocks are formed AGAIN.