Plate tectonics

Structured Questions Pack

7 marks: AO2: 5 AO3: 2 8 marks AO1: 8 10 marks AO2: 8 AO3: 2 AO1 Demonstrate knowledge and understanding of the content, concepts and processes. AO2 Analyse, interpret and evaluate geographical information, issues and view points and apply understanding in unfamiliar contexts. AO3 Select and use a variety of methods, skills and techniques (including the use of new technologies) to investigate questions and issues, reach conclusions and communicate findings. Note When there are two commands in a question; students must respond to both elements to gain good marks.

When describing a photograph, students should do more than simply ‘lift’ features from the photo.

If the question asks them to make an assessment of the quality of living that can be inferred. Hence, commentary refers to anything that is appropriate and can be inferred from the stimulus — so long as it is geographical. The student is being invited to think about the photo and reflect on it

Plate tectonics and associated hazards

Plate Movement

1) Earth structure, plate tectonics theory: convection currents and sea-

floor spreading. Evidence: continental drift and palaeomagnetism.

Study Figure 1 which is an image of the sea bed of the North Atlantic Ocean and adjacent land masses. Comment on the extent to which the features shown in the image support the theory of plate tectonics. (7 marks) GEOG3 June 11

Figure 1 shows two main elements of Plate Tectonics theory: the jigsaw fit of land either side of the Atlantic Ocean (North Africa seemingly being able to fit into the eastern side of the USA); and the mid Atlantic ridge (MAR) which is equidistant from Europe/North America, suggesting that the two areas of land mass have moved apart at an equal rate (sea-floor spreading). This appears to be a very clear representation of a constructive plate boundary, with a central rift in the MAR also being clear. However, it is perhaps better to attempt the jigsaw fit using the continental shelf as shown, rather than the shape of present day continents, but on the other hand how easy is it to do? For example, where does the protrusion of Newfoundland fit . science says to the north of the UK (Cabot Fault/ Great Glen, etc) . does this actually work? There are also seemingly a few seamounts on either side of the MAR

(Azores, Madeira, Canary Islands, Bermuda) . areas of hot spot activity? How does the extensive evidence of transform faulting fit with the theory . these are at right angles to the MAR? Students may explain these. Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple listing of features from the image such as MAR, constructive boundary, jigsaw fit, isolated mountains/volcanoes with no commentary or elaboration on any aspect. Simple statements re: theory. Level 2 (5-7 marks) (Midpoint 6) Commentary on the nature of the evidence as seen (as suggested in the nfa). Credit sophistication of description, and/or evidence of geographical thinking.

2) Destructive, constructive and conservative plate margins.

Select one plate boundary where volcanic activity is taking place.Name it, and with the aid of an annotated diagram(s) explain what is happening there as a result of the movement of the plates. (7 marks) Mark scheme Level 1 Simple statements/labels such as names of plates and density (but not both). Labelling incomplete. Sequence of events from plate movement to volcanic activity not established. (1–4 marks) Level 2 Plate labelling includes names and density (figures would indicate top of level answer).Details given, with clear sequence established from movement to volcanic activity. Particular details given on volcanic activity. (5–7 marks) Selection is very important here. You should choose a boundary with a lot of activity and where there is a clear link between the plate movement and volcanic action.The question states ‘with the aid of diagrams’, which means that you could produce some text but you

MUST draw an annotated diagram to achieve a reasonable mark.The most important point concerning the diagram is that the reader must be able to see the sequence from the initial movement of the plate to the ultimate production of volcanic activity.

Why is it more hazardous to live near destructive margins than constructive ones? (7 marks) GGA4 Jan 08

This is about impacts on humans but also requires knowledge of processes taking place at the respective margins. Comments regarding different human perspectives are also relevant. Constructive margins have relatively small land surfaces and so fewer people are directly involved. The processes of sea floor spreading and the development of (largely submarine) volcanic ridges are fairly gentle affairs and, even when hazardous, can be managed (Heimaey, Iceland 1973). Destructive margins have far more violent processes with explosive, more acidic volcanoes. Since many destructive margins are near coasts there are likely to be more people living there and so are also subjected to earthquakes and tsunamis. It is unlikely that candidates will attempt to argue against the statement but any attempt to do so should be assessed in the light of the levels criteria. Level 1 – Generic Descriptor (1 - 3) Basic statements, with general differences or reference to only one type of margin. Level 2 – Generic Descriptor (4 - 6) More detailed comments about both types of margins and understanding of either theory or impacts, probably with exemplars. Level 3 – Generic Descriptor (7) Detailed and knowledgeable comments regarding both margins with an explanation showing understanding of both theory and impact, with exemplars.

Distinguish between conservative and destructive plate margins. (7 marks) GGA4 June 09

3) Processes: seismicity and vulcanicity. Associated landforms: young

fold mountains, rift valleys, ocean ridges, deep sea trenches and island

arcs.

Describe the distribution of the earthquakes and attempt to explain the pattern that is shown. (7 marks) Mark scheme Level 1 Basic/simple statements with regard to distribution, mainly names of countries or areas affected by earthquakes. Explanation confined to plate boundaries. (1–4 marks) Level 2 Wider picture seen, such as the ‘Pacific Ring of Fire’. Some reference to the large areas where there are no or few recorded instances.More details on plate boundaries such as the name, the activity taking place there which results in earthquakes and activity within fold mountains. Some attempt to explain why some areas are free/relatively free from earthquakes. (5–7 marks) As this question is levels marked, you will receive only Level 1 marks if you describe the distribution in piecemeal form, i.e. simply a list of countries/areas. You must describe a wider pattern to reach Level 2. Similarly, explanations must go deeper than simply stating that the earthquakes are on or near plate boundaries. You could state what is happening to cause earthquakes at specific boundaries (must be those shown on the map, not earthquakes in general) such as on the conservative margin in California.

Study Figure 1, a map showing a variety of tectonic features in the Philippines. Comment on the degree to which the area of the Philippines might be subject to tectonic hazards. (7 marks) GEOG3 Jan 11

The Philippines are a hazardous area in terms of tectonic activity. The islands are surrounded by a series of ocean trenches (names could be given) which are formed at destructive plate margins. Subduction and the subsequent creation of earthquakes are therefore possible. The islands have a series of volcanoes (names again given), each of which present hazards from eruptions, pyroclastic flows and lahars. Students may be aware of previous events at Pinatubo and Mayon. Associated with these, there are a series of active faults running north/south across the island; again the possibility of plate movement and earthquakes. Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple statements of tectonic activity on the islands: listing of volcanoes, trenches. Limited or simplistic attempt to explain why these would present hazardous environments.

Level 2 (5-7 marks) (Midpoint 6) Attempts to explain or develop points made above, that suggest why the existence of tectonic features may present hazards. Some explanation of what processes must underpin an ocean trench/volcano/active fault zone and may create additional hazards. Assessment is explicit.

4) Hot spots associated with plumes of magma and their relationship to

plate movement.

Outline the formation of hot spots and explain their relationship to plate movement. (8 marks) GEOG3 Jan 11 Vulcanicity is normally associated with plate margins but, in the centre of the Pacific Ocean occur the volcanic Hawaiian islands which are not connected with any plate boundary. It is believed that this volcanic area is caused by a localised hot spot beneath the Pacific plate. A concentration of radioactive elements inside the mantle may cause such a hot spot to develop. From this, a plume of magma rises to eat into the plate above. Where lava breaks through to the surface, active volcanoes occur above the hot spot. The hot spot is stationary, so as the Pacific plate moves over it, a line of volcanoes is created. The one above the hot spot is active and the rest form a chain of islands of extinct volcanoes. The oldest volcanoes have put so much pressure on the crust that subsidence has occurred. This, together with marine erosion, has reduced some of these old volcanoes to seamounts below the level of the ocean. From this evidence it is clear that the Pacific plate is moving northwest. This is further evidence that the Earth.s crust is moving. Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple statements of process, such as location and the creation of volcanoes. No or limited references to plate movement. Level 2 (5-8 marks) (Midpoint 6) More sophisticated statements of process, such as its cause. The existence of a chain of seamounts/volcanoes with clear references to plate movement.

Vulcanicity

5) Variations in the type and frequency of volcanic activity in relation to

types of plate margin and types of lava.

In what ways does volcanic activity vary in relation to the type of plate margin along which it occurs? (10 marks) GEOG 3 June 11

Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple statements of variation of volcanic activity between plate margins. No specific detail or elaboration provided; or activity at one margin discussed well. Level 2: (5-8 marks) (Midpoint 6) Specific statements of a range of variations. Elaboration that demonstrates good understanding of the interrelationships between type and frequency of volcanic activity at plate margins. May be use of case studies to support. Level 3 (9-10 marks) (Midpoint 9) A fully developed answer, with good elaboration of a range of variations between plate margins. A rounded answer with a full comparison (most of features given in table above) of the two main types of plate margin. Good use of case studies, though not a requirement.

Living near any volcano is unwise. To what extent do you agree with this view? (7 marks) GGA4 June 08

The answer requires a debate. The view can be stated anywhere in the answer, even at the beginning. On the one-hand, volcanoes are among the most destructive natural forces on the earth. Since the 1400s, they have killed almost 200 000 people. Although many volcanoes are not dangerous, there is always a threat. Some people have little choice about where they live. Others

adopt a fatalistic approach. On the other hand volcanoes also produce benefits. For example, many volcanic materials have important industrial and chemical uses. Rock formed from lava is commonly used in building roads. Pumice is widely used for grinding and polishing. Sulphur deposits from volcanoes are used in making chemicals. Weathered volcanic ash greatly improves soil fertility which encourages agriculture. Geothermal energy is used to produce electricity. The materials they erupt help scientists learn about conditions within the earth. Many volcanoes are tourist attractions. Support can be in the form of located exemplars or detail. Level 1 – Generic Descriptor (1-3) A fairly simplistic comparison of good and bad with little or no support. An answer that only deals with positive or negative points will stay in this band. Level 2 – Generic Descriptor (4-6) A comparison of positive or negative points with some support, probably unbalanced. Level 3 – Generic Descriptor (7) A clearly stated and justified view with support for both sides of the argument.

6) Minor forms of extrusive and intrusive activity – geysers, hot springs

and boiling mud

Describe the characteristics of, and explain the formation of, minor forms of extrusive volcanic activity. (8 marks) GEOG3 June 11

Minor forms of extrusive volcanic activity include: • geysers - these occur when water, heated by volcanic activity, explodes onto the surface, for example Old Faithful, Yellowstone National Park, USA • hot springs/boiling mud - sometimes the water, heated below, does not explode onto the surface. If this water mixes with surface deposits, boiling mud is formed. Such features are very common in Iceland. There are hot springs at Bath in the west of England • solfatara - small volcanic areas without cones, produced by gases (mainly sulphurous) escaping to the surface, for example around the Bay of Naples in Italy. Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple identification of landforms, with no detail of either characteristics or formation. Imbalanced. Only one landform . max Level 1. Level 2 (5-8 marks) (Midpoint 6) Detail of either characteristics or formation, possibly with some use of supportive material. The answer progresses through the level as more is added at this level. Full mark answers are balanced.

Examine the positive impacts of volcanic activity. (7 marks) GGA4 June 07

Most of the positive impacts are economic in some way. Volcanic soils often are extremely fertile and thus are used for agriculture (Vesuvius, etc.). Igneous rocks are extremely durable and often used where ornamentation is required, such as headstones, building sills, doorframes and cornices. Volcanic sites are often higher than the surrounding land and provide defensive sites. (Edinburgh Castle on a volcanic plug, Bamburgh on the eastern edge of the Great Whin Sill). This leads in to tourism, directly in the form of Hawaii and indirectly in terms of historical sites (above); geothermal power is also relevant as is the creation of .new. land. Extension of knowledge in terms of plate tectonics and/or prediction. Negative impacts may have a place when assessing how positive an impact is. L1 Generic Descriptor (1-3) General comment on one or two positive impacts L2 Generic Descriptor (4-6) Comment on two or more impacts with some support L3 Generic Descriptor (7) Supported and organised examination of two or more developed positive impacts and/or negative implications.

7) Minor forms of intrusive activity (mark scheme below is for information only as not

assessing the correct assessment criteria, ie the answer is not levelled here)

a) Intrusive activity takes place beneath the earth.s surface through magma, which cools slowly within the crust, forming large crystals, usually granitic rock, often cracked by large joints and makes up the larger proportion of the earth.s crust. Extrusive activity takes place on the earth.s surface through lava, which cools quickly in air or water, forming small crystals, usually basaltic or andesitic rock and makes up the smaller proportion of the earth.s crust. Each mark is awarded for distinguishing between different features. This can be done by comparison (intrusive activity takes place beneath the earth.s surface, whereas extrusive activity takes place on the surface) or comparative (intrusive magma cools slower than

extrusive lava) or juxtaposition (as in the 2 paragraphs above).

b) Differences can be explicit or implicit and can refer to size, shape, and/or orientation. Batholith large, irregular, deep-seated mass of intrusive igneous rock, usually granite, with a surface area of more than 100 sq. km/40 sq mi. Laccolith intruded mass of igneous rock that forces apart two strata and forms a round lensshaped mass many times wider than thick. Can dome the surface above. Dyke a sheet of igneous rock created by the intrusion of magma across layers of pre-existing rock and therefore is discordant, can be very deep seated, usually vertical. Sill is igneous rock intruded between layers of rock and is concordant, usually relatively

shallow.

8) Major forms of extrusive activity – types of volcanoes

No Mark Schemes available

Two case studies of recent (within the last 30 years) volcanic events

should be undertaken from contrasting areas of the world. In each case,

the following should be examined:

9) The nature of the volcanic hazard With reference to two volcanic events that you have studied from contrasting areas of the world, compare the nature of the volcanic hazard and its impact. (10 marks) GEOG3 Jan 11 Vulcanologists have traditionally classified volcanoes according to the nature of the eruption. This classification is based on the degree of violence of the explosion, which is a consequence of the pressure and amount of gas in the magma and silica content of the magma. The nature of the eruption will range from quiet (Icelandic and Hawaiian) associated with basaltic lava, to moderate (Vesuvian) with andesitic lava, to violent (Krakatoan or Plinean) with rhyolitic lava. A volcanic event can have a range of impacts, affecting the area immediately around the volcano or the entire planet. Effects can be categorised into primary and secondary. Primary effects consist of:

tephra - solid material of varying grain size, from volcanic bombs to ash particles, ejected into the atmosphere

pyroclastic flows - very hot (800C), gas-charged, high-velocity flows made up of a mixture of gases and tephra

lava flows

volcanic gases - including carbon dioxide, carbon monoxide, hydrogen sulphide, sulphur dioxide and chlorine. Secondary effects include:

lahars - volcanic mud flows such as those that devastated the Colombian town of Armero after the eruption of Nevado del Ruiz in November 1985

flooding - melting of glaciers and ice caps such as the Grimsvotn glacial burst on Iceland in November 1996

tsunamis - giant sea waves generated after violent caldera-forming

events such as that which occurred on Krakatoa in 1883

volcanic landslides

climatic change - the ejection of vast amounts of volcanic debris into the atmosphere can reduce global temperatures and is believed to have been an agent in past climatic change. Volcanic effects become a hazard when they impact upon the human and built environments, killing and injuring people, burying and collapsing buildings, destroying the infrastructure and bringing agricultural activities to a halt. (10 marks)

Mark scheme Level 1 (1-4 marks) (Midpoint 3) Simple statements of nature and/or impact which could apply to any volcanic hazard. No specific detail provided. Level 2: (5-8 marks) (Midpoint 6) Specific statements of nature and/or impact which can be clearly attributed to named areas and/or volcanoes access this level. Comparison is implicit. Level 3 (9-10 marks) Midpoint 9) A fully developed answer, with good elaboration of the nature and impact of two volcanic events. A rounded answer with a full explicit comparison of the two events.

10) The impact of the event With reference to one or more examples, describe the effects of volcanic hazards on physical and human environments. (7 marks) GGB4 Jan 07

Effects will depend on the level of economic development of the country affected.

Mark scheme Level 1 simple statements of effects which could apply to any such hazard. No specific detail provided. (0-3 marks) Level 2 specific statements which can be clearly attributed to named example(s) access this level. Reserve 7 marks for consideration of both physical and human effects. (4-7 marks)

11) Management of the hazard and responses to the event.

Discuss the ways in which people and organisations have attempted to minimise the effect of volcanic eruptions. (10 marks) Mark scheme Level 1 Simple statements of responses which could apply to any volcanic eruption.Answer little more than a short list. (1–4 marks) Level 2 Recognises that there can be categories, or shows general aim behind the methods. Begins to show how such methods work with some small references to examples. (5–8 marks)

Level 3 Very clear indication that attempts can be categorised. Recognises that volcanic activity will occur and that people are unable to stop it so their main thrust should be to minimise the effects upon them.Critical evaluation made of the success of any attempts made, with clear reference to examples. (9–10 marks) As with (c), it is important to use examples, even though there is no reference to them in the question wording.As with all questions of this type, you should avoid stating only the methods that are applied.Most methods can be divided into categories and you must9 use them, because this gives a clearer insight into how people hope to minimise the effect of such hazards.

Discuss the ways in which people and organisations manage the hazard and its effects. (8 marks) GGB4 Jan 07 Again, responses to the hazards and their effects will depend on the level of economic development of the affected area. Mark scheme Level 1 simple statements of management strategies which could apply to any hazard. No specific detail provided. (0-3 marks) Level 2 specific statements of management strategies which can be clearly attributed to named hazard access this level. (4-8 marks)

Seismicity

12) The causes and main characteristics of earthquakes: focus and

epicentre; seismic waves and earthquake measurement

Explain the causes of earthquakes. (8 marks) AQA sample Level 1 (1–4 marks) Simple and generalised statements of causes of earthquakes with no real details. Specific locations are not given. Level 2 (5–8 marks) Specific and detailed causes of earthquakes are given. Good use of case studies with named plate boundaries, locations and even specific earthquakes.

Comment on the information given in Figure 1. (7 marks) AQA sample Level 1 (1–4 marks) Simple statements as to death toll and size showing some elements of correlation. Some slight indication that the correlation is not strong. Some basic attempts at commentary but with little idea why the correlation not entirely clear. Level 2 (5–7 marks) Shows a clear idea of the strength of the correlation (or lack of it) and offers evidence, particularly in terms of highest size (Mexico City) having lower toll and that of Iran with

lower size but high toll. Indicates that size is not the only factor in toll, with evidence from the information given, particularly comparing those events with similar size, i.e. Gujarat, Taiwan and Turkey.

Study Figure 1, a photograph of an area in northern Pakistan after a recent earthquake. Using Figure 1 only, comment on the evidence that suggests that an earthquake has

recently taken place. (7 marks) GEOG3 June 10

This photograph was taken in January 2006 following the October 2005 earthquake in Kashmir. There are signs of the original earthquake in the background . in the form of landslides of mud and rock (sandstones). The landslides are extensive, and very clear (whiteness). Large amounts of debris must have fallen into the valley below. There is also evidence of tented communities. An implication has to be that many of the original houses in the settlement have been destroyed or are at risk; or there have been refugees into the settlement. On the other hand, several buildings seem to be upstanding; perhaps this settlement was not as badly damaged as others in the region? There is evidence of some military presence . perhaps to act as rescuers, or to maintain order? Rubble in foreground? Mark scheme Level 1 (1-4 marks) (mid point 3) Simple listing of features from the photograph such as landslides, tented community, military lorries etc., with no commentary on any aspect. Level 2 (5-7 marks) (mid point 6) Commentary on the nature of the evidence as seen (as suggested in

the nfa). Some sophistication of description, and/or evidence of geographical thinking.

Describe how seismic waves and earthquakes can be measured. (8 marks) GEOG3 June 10

The magnitude of seismic waves and earthquakes is measured on two scales. (a) The Richter scale is a logarithmic scale - an event measured at 7 on the scale has amplitude of seismic waves ten times greater than one measured at 6 on the scale. The energy release is proportional to the magnitude, so that for each unit increase in the scale, the energy released increases by approximately 30 times. (b) The Mercalli scale measures the intensity of the event and its impact. It is a 12-point scale that runs from Level I (detected by seismometers but felt by very few people - approximately equivalent to 2 on the Richter scale) to Level XII (total destruction with the ground seen to shake - approximately 8.5 on the Richter scale). Seismic records enable earthquake frequency to be observed, but these records only date back to 1848 when an instrument capable of recording seismic waves was first developed. Candidates may provide details of both scales. Detail of the equipment and technology used, such as seismographs, is also relevant. Credit elaboration of how the technology is used or works. Mark scheme Level 1 (1-4 marks) (mid point 3) Simple references to the scales given above, increasing numbers of the scale, but without any precision in their use; or detailed explanation of one system only, including technology. Level 2 (5-8 marks) (mid point 6) Recognition that there is more than one way in which to measure seismicity . by energy levels or by impact or by technology. Some detail is given of more than one system. Also credit commentary on usefulness if given when in this level.

To what extent is the impact of an earthquake dependent on its magnitude? (7 marks) GGA4 Jan 07

This is designed to allow students an opportunity to develop ideas on the factors, which affect the impact of an earthquake. It therefore moves away from the purely numerical and locational factors and into human impact. Human factors can include density of population (Kobe), preparedness (earthquake drills, retrofitting); prediction (Pacific earthquake warning system), economic impacts (industry - Turkey, tourism - tsunami impacts on infrastructure) and also secondary impacts (disease, etc). Answers which note MEDW/LEDW differences are also creditworthy. An answer that deals solely in terms of seismology is also creditworthy; looking at wave magnitude, types of seismic waves , geological conditions, distance decay, depth of earthquake focus etc..... Level 1 . Generic Descriptor (1-3) Simplistic comments regarding either strength of earthquakes or distance from epicentre. Level 2 - Generic Descriptor (4-6) Developed comments, probably with exemplars, regarding human &/or physical factors, possibly with reference to other factors. Level 3 - Generic Descriptor (7)

A response with exemplification as to extent, which includes both references to magnitude and to other factors, sound in knowledge and understanding, referring to human and/or physical factors.

13) Tsunamis – characteristics and causes.

A tsunami can result from tectonic activity. Explain how such large waves are formed and why they can be so destructive. (8 marks) Mark scheme Level 1 Simple statements relating to cause, such as earthquakes or volcanic eruptions. Simple list of effects, with no stress on why tsunamis can be so devastating. (1–4 marks) Level 2 More detailed explanations as to the cause. Explains why tsunamis can cause such destruction, particularly the lack of preparation/perception of the hazard in the past.Details on size, penetration, etc., and indications that tsunamis may consist of more than one wave. Shows that debris in water can also be very destructive. (5–8 marks) To achieve a mark beyond Level 1 you must recognise that formation of a tsunami requires more than an earthquake/volcanic action. You must explain not only the damage that tsunamis can do, but why they can be so destructive (e.g. Indian Ocean tsunami,December 2004). Simply listing the effects will receive credit only at Level 1.

To what extent do tsunamis have less impact than earthquakes? GGA4 June 06

Question invites a debate and any view, providing it is supported and argued, is appropriate. In tsunamis the area of land affected is a relatively narrow coastal strip but this is often the most populous area (low flat land, easily developed, fishing and transport links, estuaries for routeways, often fertile, fishing and tourism). Earthquakes can cover a wider range of locations, but again, it is the human impact that will be variable depending on density of population, infrastructure, preparedness and economic ability to cope. The valid statement that the two are often (but not always) directly linked is a possible pathway to Level 3. Good support may include South East Asia tsunami December 2004, Turkish earthquakes and possibly a comparison of MEDW and LEDW. Level 1 – Generic Descriptor (1-3) Basic awareness of the large land area potentially affected by earthquakes as opposed to a narrow seaboard strip by tsunamis. Only earthquakes o tsunami. Level 2 – Generic Descriptors (4-5) Fuller knowledge/understanding with reference to examples of either earthquakes and/or tsunamis. Level 3 – Generic Descriptors (6-7) Detailed awareness of the contrasting ways in which the two impacts occur, possibly suggesting an inter-relationship between them. Judicious comment regarding the density of human settlement, technical capacity, MEDW/LEDW, tourism, etc., near the coast. Fuller knowledge/understanding with secure exemplification and text rich in detail. Comes to a supported view.

Two case studies of recent (within the last 30 years) seismic events

should be undertaken from contrasting areas of the world. In each case,

the following should be examined:

14) The nature of the seismic hazard

15) The impact of the event

With reference to one or more examples, describe the effects of seismic hazards on physical and human environments. (7 marks) GGB4 Jan 07

Effects will depend on the level of economic development of the country affected.

Mark scheme Level 1 simple statements of effects which could apply to any such hazard. No specific detail provided. (0-3 marks) Level 2 specific statements which can be clearly attributed to named example(s) access this level. Reserve 7 marks for consideration of both physical and human effects. (4-7 marks)

Describe the effects that a major earthquake can have on the population of an area. (8 marks) Mark scheme Level 1 Simple statements giving nothing more than a list of the effects. (1–4 marks) Level 2 Recognises that effects can be divided into primary and secondary and gives examples of each (accept candidate’s own definition of primary/secondary as long as it is logical). Links are clearly made between primary and secondary hazards, e.g. ground shaking can cause buildings to fall, breaking gas pipes which could lead to fires breaking out. Several effects can be linked together in a chain; another example could be ground shaking resulting in dams cracking, collapsing and leading to flooding downstream. (5–8 marks) To reach the higher mark level, you must do more than write a list of effects.With many hazards it is important to recognise that there are both primary effects and later secondary effects, which may last for a considerable period of time after the event. It is also essential to see that one effect may be the cause of another. If you can link the hazards in this way, your mark will be at the top of the range.

16) Management of the hazard and responses to the event.

With reference to two seismic events you have studied from contrasting areas of the world, compare the ways in which earthquakes and their impacts have been managed. (10 marks) GEOG3 June 10 Management may take the form of prediction, prevention or protection. Precise detail will depend on the case studies selected. The prediction of earthquakes is very difficult. Regions at risk can be identified through plate tectonics, but attempts to predict earthquakes a few hours before the event are unreliable. Such prediction is based upon monitoring groundwater levels, release of radon gas and unusual animal behaviour. Fault lines such as the San Andreas can be monitored and local magnetic fields can be measured. Areas can also be mapped on the basis of geological information and studies of ground stability to produce a hazard zone map that can be acted upon by local and national planners. Trying to prevent an earthquake is thought by most people to be impossible. This, however, has not stopped studies into the feasibility of schemes to keep the plates sliding past each other, rather than .sticking. and then releasing, which is the main cause of earthquakes. Suggestions so far for lubricating this movement have focused on using water and/or oil. Protection. Being prepared for an earthquake involves everyone from civil authorities to individuals. Protection can include any of the following:

Hazard-resistant structures: buildings can be designed to be seismic or earthquake-resistant (a great deal of detail can be given here)

Education: instructions issued by the authorities explain how to prepare for an earthquake by securing homes, appliances and heavy furniture, and getting together earthquake kits

Fire prevention: .Smart meters. have been developed which can cut off the gas if an earthquake of sufficient magnitude occurs

Emergency services: use of the emergency services in the event of an earthquake requires careful organisation and planning

Civilians are given first-aid training as trained medical personnel can take some time to arrive

The establishment of computer programs that will identify which areas the emergency services should be sent to first

Land-use planning: the most hazardous areas in the event of an earthquake can be identified and then regulated. Certain types of buildings such as schools and hospitals should be built in areas of low risk

Insurance: people are urged to take out insurance to cover their losses though this can be very expensive for individuals

Aid: most aid to developing countries has been emergency aid in the few days after the event - providing medical services, tents, water purification equipment, and search and rescue equipment. Aid over the longer term, to reconstruct the built environment and redevelop the economy, is much less readily available. (10 marks)

Mark scheme Level 1 (1-4 marks (mid point 3) Simple statements of management which could apply to any earthquake hazard. No specific detail provided. Level 2 (5-8 marks) (mid point 6) Specific statements of management strategies which can be clearly attributed to named areas and/or earthquakes access this level. Comparison must be clearly recognisable for 7/8 marks. Level 3 (9-10 marks) (mid point 9) A fully developed answer, with good elaboration of the management strategy of two seismic events. A rounded answer with a full comparison of the two events. Discuss the effectiveness of the methods used to lessen the impact of earthquakes on the population of an area. (10 marks) Mark scheme Level 1 Simple statements of methods, in effect little more than a list of the ways people can attempt to lessen the impact. (1–4 marks) Level 2 Recognises that there can be categories, or shows the general aim behind the methods. Begins to show how these methods work and how effective they have been, perhaps with some small references to located examples. (5–8 marks) Level 3 Shows a clear indication that methods can be divided into categories and discusses the purposes of such attempts.Clearly makes critical evaluations of the methods with details on how they can be made to work. Links methodology and its effectiveness with clear references to located examples. (9–10 marks) An answer which is effectively a list of methods will receive credit only at the lowest level. The key word in the question is ‘effectiveness’, and you must show to what extent the methods you quote work.Although examples are not mentioned in the question, it is a good idea to link effectiveness to real-world situations. If a particular method was effective/ineffective at a certain event, say so, as this will receive credit at the higher levels.

With reference to examples, discuss the effectiveness of hazard management schemes in areas where earthquakes have taken place. (10 marks) AQA Sample Level 1 (1–4 marks) Identifies several methods of management, but only at a superficial level. Loosely ties management techniques to specific events or areas. Examples used are very thinly developed. Material on effectiveness of schemes is little more than they work or do not work. Level 2 (5–8 marks) Clear identification of schemes and areas in which they are used. Shows, with some details, how effective such schemes can be and why they work Good use of exemplar material. Level 3 (9–10 marks) Clearly links the schemes, the areas in which they operate to their effectiveness in particular situation. Answer contains very good use of exemplar material, with some background to the events and the effectiveness of particular schemes at the time of the event.

Discuss the ways in which people and organisations manage the hazard and its effects. (8 marks) GGB4 Jan 07

Again, responses to the hazards and their effects will depend on the level of economic development of the affected area. Mark scheme Level 1 simple statements of management strategies which could apply to any hazard. No specific detail provided. (0-3 marks) Level 2 specific statements of management strategies which can be clearly attributed to named hazard access this level. (4-8 marks)