P57, 60, 66

(a)          Using Fig. 7, explain how volcanoes are formed at constructive plate boundaries.	[4]
·        plates diverge/ plates move apart ·         gap/line of weakness created ·         magma emerges through gap ·         lava solidifies to form volcanoes                1m each
(b)         Using Fig. 7, explain how plate movement results in volcanoes being formed at destructive plate boundaries. ·        plates converge/ plates move apart ·         subduction of one plate (oceanic); ·         greater density of oceanic plate; ·         friction/heating; ·         destruction of oceanic plate/turns to magma/melts; ·         build up of magma/pressure; ·         magma rises through lines of weakness; ·         lava solidifies to create volcano                1m each	[4]

Identify the relationship between the lava’s silica content, eruption temperature and resistance to flow. You are to use evidence from Fig. 10 to support your answer.                                                                                    [3]

Suggested Answer: ·        The higher the silica content and the lower the temperature, the higher the viscosity/ the lower the silica content and the higher the temperature, the lower the viscosity. [1m] ·        When the silica content is the lowest at 48 to 52% and the temperature of the lava is the highest at 1160°C, the mobility of the lava is the highest where it can flow over a wide area. [1m] ·        When the silica content is the highest at 68-77% and the temperature is the lowest at 900°C, the mobility of the lava is the lowest, where it solidifies over a short distance. [1m]

With reference to Fig. 2, suggest why Christchurch suffered more damage from the 2011 earthquake.                                                                                                                    [5]

·       In 2011, Christchurch is within the first seismic wave which is very near to the epicenter of the earthquake, while in 2010, Christchurch is at the third seismic wave. ·       In 2011, the earthquake occurred very near to the surface at a focal depth of 5km so the impact is greater. ·       Christchurch is a densely built up area with many buildings and the infrastructure is not built to withstand the stronger vibration felt in 2011. ·       In 2011, earthquake occurred at 12.51pm where many people are still in offices working when buildings collapsed, while in 2010 at 4.35am, when most people are not in high-rise offices. More liquefaction could have occurred in 2011 which makes the infrastructure unstable.

Explain how fold mountains are formed when two continental plates converge.               [4]

·       Sedimentary rocks,that make up part of the Earth's crust are softer and more flexible. ·       As two plates collide, compressional forces put sedimentary rock layers under great pressure. ·       This causes them to bend or fold. ·       As the process continues over time, the folded sedimentary rock layers rise up to great heights, forming fold mountains. SPRINGFIELD SECONDARY PRELIMS 2014 18      Study Fig. 14 which shows information about natural hazards between 1996 and 2005 in MEDCs and LEDCs. Fig. 14 (a)    Using Fig. 14,, compare the differences in the number of deaths and damage caused by natural hazards between MEDCs and LEDCs.                                                                      [4]                                                                                         ·        More killed in LEDCs (316000) /less killed in MEDCs (5700); ·        More damage in MEDCs ($150000)/less damage in LEDCs ($20000) ·        Floods caused the most number of deaths in MEDCs (3471) while drought caused the most number of deaths in LEDCs (220 879). ·        Earthquakes or tsunamis caused the most damage to MEDCs ($62 669) while volcanic eruptions caused the most damage to LEDCs ($7719) Accept other plausible answers 1m each (b)    Suggest reasons why earthquakes caused more financial damage in MEDCs than LEDCs.                                                                                                                                                            [4] ·        More workplaces/factories/offices/commercial buildings in MEDCs than LEDCs ·        Cost of replacing transport infrastructure is greater in MEDC ·        transport infrastructure is more extensive è so when earthquake strikes there will be more damages compared to LEDCs ·        Cost of replacing underground supply of water/gas/electricity is greater in MEDCs/these are more extensive in MEDCs; ·        Many expensive buildings in MEDCs/cost more to repair/higher value buildings as compared to old/flimsy buildings in LEDCs cheaper to replace Accept other plausible answer                 1m each *Study Fig. 2, which shows two earthquakes that happened in Christchurch. Fig. 2 With reference to Fig. 2, suggest why Christchurch suffered more damage from the 2011 earthquake.                                                                                                                    [5]          ·       In 2011, Christchurch is within the first seismic wave which is very near to the epicenter of the earthquake, while in 2010, Christchurch is at the third seismic wave. ·       In 2011, the earthquake occurred very near to the surface at a focal depth of 5km so the impact is greater. ·       Christchurch is a densely built up area with many buildings and the infrastructure is not built to withstand the stronger vibration felt in 2011. ·       In 2011, earthquake occurred at 12.51pm where many people are still in offices working when buildings collapsed, while in 2010 at 4.35am, when most people are not in high-rise offices. More liquefaction could have occurred in 2011 which makes the infrastructure unstable. Explain how fold mountains are formed when two continental plates converge.               [4] ·       Sedimentary rocks,that make up part of the Earth's crust are softer and more flexible. ·       As two plates collide, compressional forces put sedimentary rock layers under great pressure. ·       This causes them to bend or fold. ·       As the process continues over time, the folded sedimentary rock layers rise up to great heights, forming fold mountains.