Mechanical Weathering - The breaking down of rock into smaller pieces through stress caused by expansion and contraction., How does freeze thaw action happen? - It happens when temperatures regularly go above and below 0 degrees., Where does freeze thaw action occur? - It occurs in cold climates like an Alpine environment., What do you need for it to occur? - In order for it to occur you need a adequate water supply, pre-existing cracks and temperature fluctuations., How does Freeze thaw action work? - Water enters cracks in rocks from rivers/rain. Temperature drops at night below 0 degrees. Water expands when it freezes by approximately 9%, creating pressure inside the crack. Forces the rock to crack and deepen. Repeats for a long period of time and after a while it breaks apart.  , What happens as a result of Freeze Thaw action? - Scree is formed as a result and collects at the bottom of slopes and mountains., Where are some examples that Freeze Thaw action occur? - Croagh Patrick - Mayo and Carrantuohill - Kerry, What is exfoliation? - The process where layers of rock peel away from the surface., How does exfoliation work? - Extreme heating during the day in hot dessert regions. Outer layers expand when the rocks surface heats up much more than the inner layers cooling at night when the temperatures drop dramatically, the outer layers contract. repeated expansion and contraction creates stress between the outer and inner layers. The layers crack and peel away after time, leaving a more rounded rock surface. , Why does it occur? - This is due to the lack of clouds., Example of Exfoliation?  - Garden of gods, Colorado, USA, Two other examples of mechanical weathering? - Pressure release and salt crystallization, What is Chemical Weathering? - The breakdown of rock through Chemical reactions between minerals in the rock and substances in the earths enviroment., How does Carbonation happen? - It happens when rainwater falls through the atmosphere and combines with carbon dioxide gas, creating a weak acid solution., How does Carbonation work? - The acidic rainwater reacts with rocks containing calcium carbonate like limestone. this Carbonic acid transforms the calcium carbonate into calcium bicarbonate, which dissolves easily in water., What is the Chemical equation for carbonic acid? - H20 + CO2 =H2CO3, What is the equation for calcium bicarbonate? - CaCO3 +H2CO3 = Ca(HCO3), What is an example of Carbonation? - The Burren - Clare, 2 other forms of Chemical Weathering - Oxidation and hydration, What does Karst mean? - An area of exposed limestone that has been shaped by the chemical weathering process of carbonation., What is an example of a karst landscape? - The Burren - Clare, How is a limestone pavement formed? - Once glaciers stripped away the overlaying soil and rock, the underlying limestone is exposed to the environment. Carbonation begins, since limestone is naturally jointed and cracked, carbonic acid from rainwater starts to dissolve it. Percalation occurs as carbonic acid flows through the limestone's cracks and joints, dissolving the rock and widening the gaps. Widening and deepeningof the joints forms intersecting lines called grikes. As grikes deepen, the remaining limestone is divided into sections called clints., What is percolation? - Movement of water through pores and holes in rock., What are grikes? - Intersecting lines formed in limestone exposed to carbonation, What are clints? - Blocks of limestone divided by grikes., What are Karrens? - Small hollows that form on clints through carbonation., What is a Swallow Hole? - A narrow, funnel-shaped hole where a river flows and disappears underground., How does a Swallow hole form? - A swallow hole marks the point where a river disappears underground in a limestone region. Once the river flows into the swallow hole, it dissolves a channel underneath the surface. When water lands on Karst surfaces, it quickly disappears underground through grikes. As grikes widen and deepen through carbonation, they join with other grikes, creating a large vertical passage. The river flows into this passage and disappears underground. Eventually the roof of the passage weakens and collapses, opening up the swallow hole.  , What is a Turlough? - The hollows that fill with water on the limestone pavement., What is a Dry Valley? - It is formed downstream as a river is no longer flowing., An example of a Dripstone feature? - Ailwee Cave - Clare, How are Stalactites formed? - They are formed hanging from the roof as more and more calcite is deposited. Drops of water containing dissolved limestone seep down through cracks/fissures in the cave roof., How are Stalagmites formed? - Evaporations lead to calcite water droplets falling to the floor. Drops of water lose carbon dioxide and deposit calcite. Over time leaving to the formation of stalagmites., What are pillars? - They are when stalactites and stalagmites grow into each other and join to form pillars., How are Curtains formed? - Rain water drips from a long crack in a cave roof and forms a continuous stripe of calcite , An Example of a Cave - Ailwee Caves - Clare, How do caves form? - Forms by solution when carbanation occurs making the caves and caverns wider. Hydraulic action when the force of moving water in underground streams. Abrasion happens when streams pick up sediments and material as it goes along. This causes the cave to widen and deepen. , What is a Cave? - Unde3rground passage with underground chambers called caverns. Found below the zone of saturation.,

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