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Feat of strength?

Learn about the legend of the Blarney Stone and the geological process of gradation involving weathering, transportation, deposition, and denudation. Discover how physical and chemical weathering shapes landscapes.

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Feat of strength?

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  1. Feat of strength?

  2. THE BLARNEY STONE Derived from the “Scone of Stone” used in coronation ceremonies of Scottish Kings Given as gift by Robert the Bruce – “BRAVEHEART” According to legend, kissing the stone endows the kisser with the gift of gab(great eloquence or skill at flattery).

  3. GRADATION 3 stages? Weathering - Transportation - Deposition

  4. Denundation Breaking down of rock via physical & chemical processes Weathering (in place) Degradation Gradation Erosion(transportation) Aggradation Process that builds up the Earth’s surface through deposition of material Breaking down & removal of rock Resultsin levelling the land to: BASE LEVEL Bill Nye Intro Video Clip

  5. Physical (mechanical) Weathering • More prominent in ___________ regions arid,cold • No change in chemical composition--just …..?

  6. Increases the exposed surface area of rock, making it more vulnerable to further physical and chemical weathering Reduces rock material to smaller fragments that are easier to transport Joint-block separation and granular disintegration are two common forms of bedrock disintegration.

  7. Why do edges weather more quickly?

  8. Rates of weathering Joints _______ in a rock are a pathway for water – they can enhance mechanical weathering

  9. Rock breakdown caused by expansion of ice in cracks and joints is called: Frost wedging

  10. Physical Weathering Ice crystal growth within the joint planes of rock can cause the rock to split apart because ice expands by _____? 10%

  11. Name of feature? Talus or scree slope

  12. Shattered rocks are common in cold and alpine environments where repeated freeze-thaw cycles gradually pry rocks apart.

  13. 2 adjectives to describe the landscape? jagged rough sharp edges shattered

  14. Type of weathering? Crystal growth What happens to the water? Evaporation occurs

  15. Salt Formation Areas • Coastal regions. • Arid regions. • Urban areas. • Along highways.

  16. Physical Weathering Exfoliation (Pressure Release; Unloading) When overlying material is removed, the pressures on underlying layers of rock lessen. = Expansion Consequently, rocks exposed at the surface may break apart Eg. Retreating ice sheets

  17. Exfoliation – Pressure Release

  18. Physical WeatheringExfoliation – Pressure Release This granite outcrop in Yosemite National Park, California, displays sheetlike joints, giving a stepped appearance to the mountain slope.

  19. Weathering due to the extreme range of temperatures (can shatter rocks in desert environments.) is called? Thermal Expansion Repeated swelling and shrinking of minerals with different expansion rates will also shatter rocks. Weathering

  20. Physical Weathering Human, animal, vegetable

  21. Periglacial landscapes (Physical Weathering)

  22. Ice Wedge Formation I

  23. Weathered regolith (freeze-thaw)

  24. blockfields surfaces covered by rock rubble derived largely from weathering of the underlying but largely hidden bedrock

  25. Frost Heaving -heavy dense cold air • Groundwater rises • Freezes & soil expands

  26. Pingo

  27. Palsas

  28. Stone Polygons

  29. Polygons & Pingo

  30. Polygons

  31. Pressure release

  32. Tors

  33. Frost Creep “Soilfluction” (type of mass wastage)

  34. Periglacial: Frailties • Vegetation – easily disturbed • Animal populations – sensitive to change • Low energy – slow decomposition • Thermal Expansion of permafrost: • Soil/Vegetation removed = thaw • Housing = heat • Pipelnes = crack • Drilling = heat • Short Term Economic Gain • Long Term Environmental Destruction

  35. Chemical Physical Type of weathering in forefround? Type of weathering in the background?

  36. Chemical Solution (Dissolution) • Water is the main operator: • Many ionic and organic compounds dissolve in water • Silica, K, Mg • Acid Reactions • Water + carbon dioxide <---> carbonic acid • Water + sulfur <---> sulfuric acid • Effective at breaking down minerals TYPE OF WEATHERING?

  37. Solutionweathering • Water becomes acidic as ________________ dissolves in it to create a weak carbonic acid. • Carbonate rocks such as react with carbonic acid, to create a weaker form that is removed by solution. Carbon dioxide limestone Sinkhole

  38. Spheroidal weathering is caused by chemical weathering of jointed rocks. The jointed rocks weather to form roughly spherical shapes.

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