Welcome to GCSE Geography. Where will it take us today?

Transcription

1 Welcome to GCSE Geography Where will it take us today?

2

3 Topic 1.2: global hazards 1.2a: What processes plate boundaries aiii) How the movement of tectonic plates causes volcanoes 06/12/2018

4 Think back.. Name the layers of the Earth Name 4 types of plate boundary Gets its name because land is neither made nor destroyed Push and Pull of the tectonic World P.R.O.F volcano zone Density of oceanic plates Shallow focus earthquake zone Caused the Himalayas Caused the Rift Valley Another term for conservative plates Cause of hotspots Where an earthquake hits the surface How many points can you rack up?

5 Plate Movement & volcanic activity Learning is successful now I can: Explain the cause of volcanoes Suggest reasons for the distribution of volcanic activity Outline the characteristics of shield and composite volcanoes Impressive Vocabulary Keywords Shield Composite Viscous Ash Lava Pyroclastic flow lahar Geography Skills: Scale Conceptual understanding Literacy Skills: Reading for meaning Exam writing Employability Skills: Independent thinking Time management

6 PRESENT NEW INFORMATION LOOK, LISTEN, LEARN

7 Plate Movement & volcanic activity Volcanoes occur at which two of the four plate boundaries? Why is this? [draw some diagrams to help you think this through] True or False volcanoes only occur along plate boundaries?

8 CONSOLIDATION: HOTSPOT VOLCANOES Watch carefully. Don t take notes. Think carefully about how the hotspot volcanoes are formed.

9 We re going to Hawaii!!! You have been given a job at Hawaii Volcanoes National park as a tour guide. You have to explain how the volcanoes are formed in less than 1 minute at the beginning of your tour! End You have 5 minutes planning time!

10 Watch the video again check your work and add anything that you have missed out of your initial plan You have 2 minutes reviewing time! End

11 Alloa!! Welcome to Hawaii Volcanoes National Park. My name is and I ll be your guide today!

12 There are two types of volcano S C _

13 COMPOSITE AND SHIELD A B Besides shape, how else might these two types of volcano be Similar? Different? Discuss your points with nearby neighbours Challenge: Anatomy of a volcano grab yourself a volcano and label its key features

14 The anatomy of a volcano Page 39 Volcanic bomb Secondary vent Magma chamber Old layers of lava crater Ash cloud Old layers of ash Lava flow Fumarole Magma conduit (main vent)

15 Composite vs Shield Destructive Layers of ash and lava Tall cone, narrow base Acidic lava Irregular eruptions with long dormant periods Can be violent explosions Steam, gas & viscous lava are ejected; lahars & pyroclastic flows possible Main vent can become plugged Etna, Vesuvius, Stromboli Italy, Krakatoa - Indonesia Constructive Lava only Wide based cone, gentle slopes Alkaline lava Regular and frequent eruptions Lava pours down sides not violent Main vent never gets plugged Hekla, Surtsey Iceland Mauna Loa, Kilauea - Hawaii

16 Composite Shield

17 Apply what you know 1. What type of volcano will be found at A? [1] 2. What type of volcano will be found at B? [1] 3. Explain your thinking [4]

18 THE ALIENS ARE STAYING A B Final decision time Which one would you choose to live by? Why?

19 Multiple Choice 6/8 Marks Short Short Answer Answer Case Study Describe and explain two features of the global distribution of volcanoes (4)

20 Give yourself a mark our of 4 and add anything you missed in purple pen Feature 1 Most volcanoes are found at plate boundaries Feature 2 Some volcanoes are found in the middle of plates Because this is where plates diverge or converge allowing volcanoes to form Because these are hotspot volcanoes

21 Stock-check Update your keyword list composite shield Viscous magma Lava Pyroclastic flow Lit.Checklist Peer assess, get your work checked. Accuracy Spelling Grammar PLC Checklist Track your coverage and assess your confidence

22 WHAT WOULD AN EXAM QUESTION LOOK LIKE? Explain how the movement of tectonic plates causes different types of volcano [6] 8 mins Steps to Success 1. Box 2. Underline 3. Lingo to include.. 4. Write it! Remember to Glance back 5. Spell- check * Point Explain Evidence Evaluation Link S H E E P Place Specific Detail

23 WHAT WOULD AN EXAM ANSWER LOOK LIKE? Explain how the movement of tectonic plates causes different types of volcano [6] Page 38/39 6 mins peer assess There are two main types of volcano, shield and composite [1?]. Shield volcanoes occur at constructive plate margins, where the plates diverge and the mantle rises to the surface [1]. Eruptions are gentle and lava is runny due to the lower pressure [1], so the volcanoes are flatter in shape [1]. Composite volcanoes occur at destructive plate margins, where plates converge [1]. Semi molten magma contains seawater and trapped gases, which builds pressure [1]. When released, the viscous lava travels slowly, creating a steep sided volcano. Escaping ash adds layers to the volcano [1].

24 Plate Movement & volcanic activity Learning is successful when I can: Explain the cause of volcanoes Suggest reasons for the distribution of volcanic activity Outline the characteristics of shield and composite volcanoes Impressive Vocabulary Keywords Shield Composite Viscous Ash Lava Pyroclastic flow Geography Skills: Scale Conceptual understanding Literacy Skills: Reading for meaning Exam writing Employability Skills: Independent thinking Time management