Geology Lesson 1 – Erosion and Weathering Lesson 2 – Rock Investigations Mrs Breward Monday, 10 May 2021 DO NOW TASK: Rock cycle quiz TASK- Complete the following quiz in your book. Get ready to self-assess with RED and PURPLE pens. 1. Does the rock cycle ever stop? 2. What are the 3 categories of rock? Geology- the study of rocks. No Sedimentary, Igneous, Metamorphic 3. Could a rock go from sedimentary rock to metamorphic rock? Yes 4. Could a metamorphic rock became an igneous rock? Yes 5. Could a rock go through the entire cycle in our lifetime? No 6. Does geology move quickly or slowly compared to our lives? Slowly What is the same? What is different? Did one cause the other? Justify your answer. Erosion and weathering Tuesday, 22 February 2022 Learning objectives Grade 3/4 – Recall how rocks can be damaged over time. Grade 5/6 – Explain why some rocks are more affected by weathering than others. Grade 7/8 – Predict how much rocks will be affected by weathering in a given situation. Rock cycle recap The Earth, and Rocks are always changing… very simply, this is how it works: Sedimentary rock Igneous rock Metamorphic rock Three types of rocks RECAP. Sedimentary rock: Formed by sediment settling over time (e.g. bottom of ocean) Metamorphic rock: Formed from other rocks that have been changed due to heat and pressure Igneous rock: Formed when magma (molten rock) cools and hardens EXTENSION- What do you think the Rock cycle is so far? Write a definition in your books. https://youtu.be/SuNfbEDMOQs 1. What are the 3 types of rock? (1) 2. Describe how fossils are formed in sedimentary rocks. (3) 3. Explain how marble is formed from limestone (2) Answers 1. Igneous, sedimentary and metamorphic. 2. An explanation linking three of the following points: • dead animals / plants (1) • (dead animals / plants) become covered in sediment (1) (Allow covered in sand / rock / limestone) • are {squashed / crushed /compacted / pressured} (as layers of sediment build up on top of one another) (1) • long time period (1) • fossils are caused by skeletons/bones / shells / remains (1) Answers! 3. An explanation linking the following points: (limestone is subject to) • heat(1) • and pressure (1) (from the surrounding earth) Ignore melting / magma / lava Ignore crushed Freeze-Thaw Exfoliation https://yout u.be/qGw1y B10lX0 Weathering Biological Chemical Weathering and erosion What is the difference between weathering and erosion? Weathering BREAKS down the rock into sediment, erosion MOVES the sediment to new places Explaining weathering Read the steps that cause each type of weathering. Put them into the correct order. Explaining weathering Put the steps into the correct order Freeze-thaw Exfoliation 1 Water gets into crack 1 Rock heated by sun and expands 2 Water freezes and expands 2 Rock cools down and contracts 3 Crack is opened up 3 Rock weakened 4 Rock falls to pieces 4 Surface layers of rock peel off Biological weathering Chemical weathering 1 Seeds fall into crack 1 Rainwater contains weak acid 2 Crack provides moisture and shelter 2 Acid attacks rock 3 Roots grow 3 Rock dissolved or weakened 4 Crack widens and rock breaks up 4 Rock worn away or broken up Questions 1) Why are roads in Canada most likely to be affected by freezethaw weathering? 2) Why would a patio be likely to suffer from biological weathering? 3) Why has the Great Sphynx of Egypt suffered from exfoliation? Lesson 2: Becoming a rock detective… https://youtu.be/R5Qz2Zil3dQ Learning objectives Grade 3/4 – Identify some types of rock from samples Grade 5/6 – Evaluate rock structure to determine its type Grade 7/8 – Explain the characteristics of different rock types Crystal structures • Think about the mineral salt. • It is made of cube- shaped crystals. • No matter where you find it, on your table or at the beach, its crystals will be shaped like cubes. • Use your hand lens to study the rock salt. The same mineral can have different colours. This is caused by small amounts of different elements that got into the mineral when it was forming. While the colour of a mineral may vary, its crystal shape is always the same. For example, diamonds can be clear, yellow, pink, and even blue, but its crystals will always have eight faces (sides). Rock structure Become a geologist • Measure and weigh your rock sample • Identify each sample as either sedimentary, metamorphic or igneous. • Study the structure of grains and crystals, can you see any shapes? • Does the rock feel smooth or rough? • Record your observations Metamorphic Sandstone Marble pressure schist heat sedimentary igneous limestone magma sedimentary igneous etamorphic heat schist chist imestone marble magma pressure Session 2 Volcanoes, earthquakes and tsunamis DO NOW TASK The properties of Igneous Rocks. • Igneous Rocks are very strong and do not erode (wear away) easily. Most mountains are made of Igneous Rock. • They are strong because they contain crystals. • These crystals also make them non-porous. This means that there are no holes in the rock surface and water (or other liquids) will not soak into it. Volcanoes What’s the difference between magma and lava? Igneous rocks form from the solidification of once-molten rock material. When this mushy melt is found underground penetrating other rocks, it's called magma, and the solidified rock is termed intrusive. By contrast, molten material that has erupted onto the Earth's surface is named lava, which cools into what geologists call extrusive (or volcanic) rocks. What type of Igneous Rock will form at A? A Intrusive Igneous Rock What type of Igneous Rock will form at B? B Extrusive Igneous Rock Volcanoes • Some volcanoes explode with the force of an atomic bomb. Others spill rivers of gently flowing lava. • Make notes during the presentation to answer the questions on your worksheet. https://www.amnh.org/explore/ology/earth/volcanoesmagma-rising The Saint-Pierre Volcanic Disaster 1902 1. What is the name given to an eruption of hot gases, ash and rocks? Pyroclastic flow 2. How fast does it travel? 480 kmh / 300 mph 3. On what date did the earthquakes begin? April 23rd 1902 4. What was the first material to affect a nearby town and when did it occur? Ash on May 2nd 1902 5. How high did the column of ash and fumes rise from Mount Pelée? 3km / 2miles 6. What killed 23 people? Mudflow 7. How long did the tsunami take to reach Saint-Pierre? 15 minutes 8. How many people were killed by the pyroclastic flow from Mount Soufrière? 1,565 9. On what two dates did Mount Pierre erupt? May 8th and May 20th 10. What type of rock do you think created the 300m “Needle of Pelée”? Pumice 11. Why do you think it is important to know about historical volcanic eruptions? Volcanic eruptions are one of Earth's most dramatic and violent agents of change. Not only can they drastically alter land and water for miles around a volcano, but tiny liquid droplets of sulfuric acid erupted into the stratosphere can change our planet's climate temporarily. A lava spine can either be formed by viscous lava slowly being pushed out of the vent, or by magma that has solidified within the vent before being pushed out. How acid rain forms The term 'acid rain' refers to rainfall containing strong acids. These can originate from both natural sources and human activity. Volcanic acid rain (pH 2.5-5.0) is dominated by hydrochloric acid (HCl) and sulfuric acid (H2SO4) . Acid rain practical You are going to test some rock samples for the presence of carbonate minerals. How could you increase the rate of the reaction in these tests? Use ONE drop only! GOGGLES AT ALL TIMES! Name of rock Effect of adding acid What causes the fizz? Carbonate minerals are unstable in contact with hydrochloric acid. When acid begins to effervesce (fizz) on a specimen, a reaction similar to the one shown below is taking place. CaCO3 + 2HCl → CO2 + H2O + Ca++ + 2Cl– On the left side of this reaction, the mineral calcite (CaCO3) is in contact with hydrochloric acid (HCl). These react to form carbon dioxide gas (CO2), water (H2O), dissolved calcium (Ca++), and dissolved chlorine (Cl--). The carbon dioxide bubbles that you observe are evidence that the reaction is taking place. When that occurs, calcite or another carbonate mineral is present. Environmental affects of acid rain Lesson 4: Earthquakes and Tsunamis What do the yellow lines on this map show? What are earthquakes? What are plate margins? DESTRUCTIVE CONSERVATIVE Earthquakes are vibrations caused by earth movements at plate margins and at major fault lines (cracks in the earth’s surface). They can occur at all major plate margins but the most severe earthquakes are normally found at CONSERVATIVE and DESTRUCTIVE margins. Earthquake data Look at today’s data from the USGS and plot the earthquakes on your map. • What do you notice? • Draw a red line around the ‘Ring of Fire’ • What is the size, depth and location of the largest earthquake today? https://earthquake.usgs.gov/earthquakes/map/?cur rentFeatureId=ak0217timl90&extent=-12.03932,201.79688&extent=68.72044,11.95313 What do you think a tsunami is? Tsunami is a Japanese word. It means ‘Harbour Wave’. A tsunami is a giant wave. Was your idea close to the real meaning? • A tsunami is a giant wave caused by a huge earthquake under the ocean. • The earthquake causes a large amount of water to be displaced very quickly. • A series of waves travels through the deep water. • As the waves travel through shallower water near the land, they get bigger. Did you know... before the tall wave hits the land, the water level at the shore will drop? Watch this video which shows how a tsunami is formed. What can you see that looks out of place? What kinds of damage have occurred in the area? If you were in a rescue team who have just arrived at the scene, what kinds of help might you need to give? Photo courtesy of Official US Navy page (@flikr.com) – granted under creative commons licence - attribution What Causes a Tsunami? Approaching tsunamis are sometimes predicted by a sudden rise or fall of coastal waters and are usually accompanied by a loud roar that sounds like a train or aircraft. If you notice these, move inland to high ground straight away. Stay out of danger until an "ALL CLEAR" is issued by the emergency services. Homes and other buildings located in low lying coastal areas are not safe. Do NOT stay in such buildings if there is a tsunami warning. The upper floors of high, multi-story, reinforced concrete hotels can provide safety if there is no time to quickly move inland or to higher ground. Never go down to the beach to watch for a tsunami! A small tsunami at one beach can be a giant a few miles away. Stay tuned to your local radio or television stations during a tsunami emergency. Japan – 2011 At 2:46pm, an 8.9 magnitude earthquake struck the north east coast of Japan. The quake triggered a huge tsunami which swept inland. In places, the tsunami waves reached as far as 10k inland and entire towns virtually disappeared. Japan has the longest recorded history of tsunamis. Sumatra, Indonesia – 2004 This Indian Ocean earthquake and tsunami was the most devastating of its kind in modern times, killing 230,000 people in 14 countries, and bringing waves of up to 30m high. It was the third largest earthquake ever recorded, had the longest duration ever observed (8.3 - 10 minutes), and caused the entire planet to vibrate. Lisbon – 1755 The earthquake and tsunami almost totally destroyed Lisbon and had a death toll in Lisbon alone of between 10,000 and 100,000 people, making it one of the deadliest disasters in history. Italy – 1908 The Messina earthquake and tsunami took about 123,000 lives in Sicily and Calabria, southern Italy. The major cities of Messina and Reggio Calabria were almost completely destroyed. Italy - 1783 The Calabrian earthquakes were a sequence of five strong earthquakes that hit the region of Calabria, the first two of which produced tsunamis. The death toll lies in the range of 32,000 to 50,000 people. https://youtu.be/Wx9vPv-T51I Tsunamis Complete the Tsunami worksheet Session 3 – Could you be a geologist? https://www.geolsoc.org.uk/careerprofiles Exit ticket- Exam questions Have you been inspired to study geology today? • https://youtu.be/O8HNlhVbGzY - Dante’s Peak film trailer 1997 Mark in RED Improve in PURPLE Mark in RED Improve in PURPLE Mark in RED Improve in PURPLE Mark in RED Improve in PURPLE Mark in RED Improve in PURPLE Mark in RED Improve in PURPLE