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Edexcel GCSE Geography A-Unit 2 Section A Topic 4: Tectonic LandscapesSome questions will be from 4.1 and some from 4.2.

4.1 Location and characteristics of tectonic activity.

(I) World distribution of earthquakes and volcanoes To be able to describe the distribution of earthquakes and volcanic eruptions on a global scale(II) The reasons why earthquakes and volcanoes occur where they do, through an explanation of plate tectonics and hotspots. To understand the processes that cause plate movement in relation to earthquakes and volcanoes. To understand how hotspots form.(III) The characteristic features of convergent, divergent and conservative plate boundaries. To be able to draw cross-section diagrams annotated with the features of each plate boundary.(IV) The measurement of earthquake magnitude (the Mercalli and Richter scales). Diagrams showing the characteristics of focus and epicentre. To be able to recognise and know the difference between the Mercalli and Richter scales, and the characteristics of the epicentre and focus of earthquakes.Questions from sample and past papers

(i) Describe the landforms A and B shown on Figure 4a. (4)

A = Ocean trench (1), deep (1), narrow (1).

B= Subduction zone (1), area of crustal melting (1),

Correct identification 1 mark for each. 1 mark for any relevant descriptive point.(ii) Landform C shown on Figure 4a is an area of fold mountains. Explain how they are formed. You may use a diagram to help your answer. (4)Explanation to include four points given from:

Formation when plates collide (1), buckling of continental plate (1), leading to long band (1), of highly crumpled crust (1).(b) The plate boundary illustrated in Figure 4a is a destructive one. Some plate boundaries are known as constructive.

(i) Explain the processes that take place at constructive plate boundaries. (4)Explanation to include four points given from:

Convection currents in the mantle (1), cause magma to rise (1), spreading out and moving crust apart (1),forming volcanoes (1), mid-ocean ridges (1), earthquakes result (1).

(ii) Study Figure 4b .

It is a map showing the global distribution of volcanoes.

Explain why the distribution of volcanoes is very uneven. (3)

Uneven because they occur at plate boundaries (1), plate boundaries are linear hence lines of volcanoes (1), plate boundaries often close to continental margins (1), destructive margins (1), constructive margins in mid-ocean (1).

(i) Name the tectonic plate on which Australia is located on Figure 4b. (1)Indo-Australian plateii) Describe the distribution of active volcanoes on Figure 4b. (3)Mark all descriptive points at one mark each. Any valid point acceptable:

in a ring around the Pacific

on plate boundaries

odd ones not on plate boundary

clusters on the margins of continents

none in Australia(iii) Volcanic activity is happening at point A. Explain why. (4)Explanation of hotspots. Max 2 marks for descriptive points. Credit explanations at 1 mark each. Max of 3 marks without a mention of process.

Full marks can only be achieved if there is a clear sequence of events.

Island chains such as Hawaii are known as hotspots, (1) where magma from the mantle (1) erupts through the crust. (1) This creates volcanoes (1) that often

rise above the ocean surface to form islands. (1) The Hawaiian chain formed as the Pacific crustal plate moved over the stationary source of magma or hotspot. (1)(i) What is the epicentre of an earthquake? (1)The point on the surface above the focus.(iii) The area in Figure 4b is near the epicentre. What is the epicentre? (1)The point on the surface, above the focus where most damage occurs (1) Point where the earthquake first strikes the surface(1)(i) Which type of plate boundary is shown in Figure 4a? (1) Convergent (accept destructive)(ii) Draw arrows on Figure 4a to show the direction of plate movement. (1)Arrows should reflect plate movements towards each other Must show two arrows for mark(iii) Name the type of plate shown at A on Figure 4a. (1)Continental

(iv) Explain how volcanoes form at this plate boundary. You may use a diagram in your answer. (4)Melting of oceanic plate produces magma (1). Collection of magma in magma chamber. This rises under pressure/less dense than surrounding rock (1)Through cracks and joints (1) Gas/Water Vapour is added to melt (1) Magma only erupts under great pressure therefore eruptions explosive (1)

Max 2 for descriptive points, explanations credited at 1 mark each. Full sequence required for full marks.(a) Study Figure 4a. It shows the magnitude of earthquakes on 23rd August 2009.

(i) Which area had the largest earthquake on the 23rd August 2009? (1) Alaska. Accept North West North America(ii) Describe the distribution of earthquakes shown on Figure 4a. Use evidence from Figure 4a in your answer. (4)Max 3 without evidence which can data, places eg west of USA, or size of earthquake.

1 mark for evidence or data

Linear (1) Near coast (1) At the plate boundaries (1) Clustered (1) Mainly in western USA and Alaska (1)(iii) Outline a difference between the focus and epicentre of an earthquake. (2)Focus origin of earthquake (1) Epicentre point on surface directly above focus

with greatest effects (1)

Difference can be implied with use of terms whereas or however.(iii) The island of Lanzarote has been formed over a hotspot. Explain how volcanoes form over hotspots. Use an annotated diagram or diagrams in your answer. (4)Explanation of hotspots. Max 2 marks for descriptive points. Max of 3 marks without a mention of process. Max of three without annotated diagram

Magma rises as mantle plumes towards the surface (1) At the surface the magma erupts through the crust.(1) This creates volcanoes(1) that often rise above the ocean surface to form islands.(1) The Canary Islands formed as the crustal plate moved over the stationary source hotspot. (1)

(i) Which point V, W, X or Y on the Mid-Atlantic Ridge has the most movement

per year? (1) Y(ii) Describe the movements shown along this plate boundary. (3)Point mark.

Plates are moving apart (1)Use of data (1) Different rates of movement (1) Faster at Y (1)(iii) On Figure 4a there are four red spots marked 1 to 4. Which red spot shows the location of a volcano? (1) 1(iv) Explain how volcanoes occur at divergent plate boundaries. (4)Maximum 2 marks for description. Explanations credited at 1 mark each.

Max 3 marks without a process or full sequence. E.g. - Formation of volcanoes at DPB: Magma rises due to convection currents, leading to pressure and doming of the crust (oceanic). Magma rises through the weaknesses in the crust. Eventually (low viscosity) magma erupts onto the surface. The continued movement of plates pulls the plates apart leading to more effusive eruptions.(v) Compare the characteristic features of convergent plate boundaries and

conservative plate boundaries. (4)Max three without comparative statements. Max 2 if only reference to one of the required elements. Convergent characteristic features to include fold mountains, subduction zones, trenches, volcanoes (explosive) and earthquake activity. Conservative creates rifts or faults leading to lateral movement of the ground and earthquakes. E.g. At a convergent plate boundary plates subduction can lead to earthquake formation (1) due to pressure build up between two plates (1). Earthquakes also occur at conservative plate boundaries on fault lines (1), but due to tension (1). Subduction of the oceanic plate leads to magma formation and explosive volcanic eruptions (1). No magma is created at conservative plate boundaries (1) therefore there are no volcanic eruptions (1).

(i) The dates of seven volcanic eruptions are shown on Figure 4a. Which one occurred before 1950? (1) Krakatoa(ii) Describe the distribution of volcanoes shown in Figure 4a. Use evidence from Figure 4a in your answer. (4)Point mark. Max 3 without map evidence.

E.g. In chains/lines (1) along the coast (1) Clustered together (1)Along plate boundaries (1)

Some found in centre of ocean (1) Example of place (1)

Map evidence includes place names, dates, plate (boundary) names.(iii) The volcano Kilauea shown on Figure 4a is found in the middle of a plate. What type of volcano is this? (1) Hotspot (iv) Explain the formation of volcanoes at convergent plate boundaries. You may use a diagram(s) in your answer. (4)Maximum 2 marks for description. Explanations credited at 1 mark each. Max 3 marks without a process or full sequence.

E.g. Movement of plate towards each other leads to subduction of the denser oceanic plate. High

temperatures and friction lead to the melting of the leading edge of the plate. Less dense melt rises

through the mantle wedge, and pressurises the continental crust. Cracking of the continental crust

due to collision provides a path for rising magma. Rising magma contains gas and is highly

pressurised leading to explosive eruptions. Explanation can be achieved through reference to

subduction, melting, low density rising magma, and build up of pressure.

4.2 Management of the effects of tectonic activity.

(I) The reasons why people continue to live in areas of volcanic and earthquake activity. To understand the economic, social and environmental reasons why people continue to live in areas of volcanic and earthquake activity.(II) The causes and effects of a volcano eruption on people and the environment, in a named location. To be able to describe and explain the causes and effects of a volcanic eruption on the people and the environment, e.g. in Montserrat.(iii) Prediction and prevention of the effe