Session 1 1. Define hazard? o Hazard means an event which has the potential to cause a disaster, and can be either natural or man-made.

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1 Session 1 1. Define hazard? o Hazard means an event which has the potential to cause a disaster, and can be either natural or man-made. 2. In what form can hazards be classified? o natural hazards and o man-made hazards. 3. How many types of natural hazards do we have? o Two (2) 4. Name them and give three examples of each type? o Examples of fast impact natural hazards include earthquakes, floods, cyclones, hurricanes, tornadoes, landslides, tsunami, volcanic eruption, insect infestation and wild-fires. o Slow onset natural hazards include epidemics of biological origin (e.g. SARS, Bird Flu, Ebola), drought, and famine. 5. How many types of man-made hazards do we have? o Two (2) 6. Name them and give three examples of each type? o Sudden man-made hazards include transport, structural and technological accidents (e.g. chemical spill, fire) o Long term man-made hazards (e.g. nuclear generator failure). 7. What is vulnerability? o It is defined as the extent to which a community, structure, service, and/or geographic area is likely to be damaged or disrupted by the impact of a particular hazard, on account of their nature, construction and proximity to hazardous terrain or a disaster prone area. 8. What is Disaster? o A sudden, adverse event bringing great damage, loss, great distress, destruction and devastation to life and property. 9. Identify the various ways through which disaster can be prevented? o Eliminate Hazard No Disaster o Eliminate Vulnerability No Disaster o Keep Hazard and Vulnerability Apart. o Reduce Vulnerability and/or hazard, especially human-induced hazard.

2 Session Two (2) 10. The earth as a planet makes three main movement in space. What are they o Sidereal day (Rotates on its axis, 23hrs, 56min,4 sec) o Sidereal year (Orbits the sun, taking 365 days, 6 hours, 9 mins, 10 sec) o Moves through the Milky Way with the rest of the solar system. The orbit of the earth round the sun covers a distance of 958,000,000 km. 11. The Earth s physical environment is traditionally divided into three major parts, name them o the Atmosphere, o Hydrosphere o Solid Earth s Surface (Land). (Lithosphere) 12. Explain the following o Atmosphere o Hydrosphere o biosphere 13. The largest bodies of land are called? o Continent 14. The earth s interior consists of three major zones defined by their chemical composition. True or fasle? o True 15. Identify the three major zones of the earth s interior? o Crust o Mantle o Core 16. The crust is divided into how many layers? Name them? o two o Continental o Oceanic 17. Differentiate between continental crust and oceanic crust? Continental crust o Upper continental crust composed of lighter, granitic rocks, o Lower continental crust is more similar to basalt, o Average density is about 2.7 g/cm 3 o It is up to 4 billion years old Oceanic crust o It is basaltic composition, o Density about 3.0 g/cm 3 o Younger (180 million years or less) than the continental crust 18. The crust and the uppermost mantle are referred to as.?

3 o Lithosphere 19. What is an Asthenosphere? o It is a hot, weak zone comprised of molten that is capable of gradual flow, on which lies the lithosphere or plates. 20. The core is divided into how many layers? name them o two o Inner core o outer core 21. The inner core of the earth s interior behaves like a liquid, true or false? o False 22. Name the two major force fields that influence the earth o Gravity (caused by gravitation) o Magnetism 23. Briefly explain the theory of plate tectonism? o The theory of plate tectonics, describes the mobile earth, and holds that the outer, rigid layer of Earth consists of about a dozen major segments called Plates. Plates form the Earth s rigid outer shell called the lithosphere. The lithosphere overlies a zone of weaker and hotter material known as the Asthenosphere, and the former moves over the latter. o The plates are assumed to be rigid, thus move as a distinct unit. As the plates move, the distance between two points on the same plate remains constant but distance between two points on different plates continually changes. o All major interactions between plates occur along their margins. 24. According to., most earthquakes, volcanisms and mountain building occur along plate boundary? o Theory of plate tectonism 25. How many types of plate boundaries do we have? o Three (3) 26. Name and explain them? o Divergent boundaries (plates move apart resulting in upwelling of material from the mantle to create new ocean floor. As the plates spread apart, the gap is filed with molten rock that oozes up from the hot mantle: new crust is created at an average of 5 centimetres each year. o Convergent Boundaries (where older weak crust are destroyed and submerged by plates moving together o Transform faults (plates neither meet or drift apart but slide past each other

4 Session Three (3) 27. What is an earthquake? o An earthquake is the vibration of Earth produced by the rapid release of energy 28. Where do earthquakes occur? o Occur along tectonic plate boundaries and large fractures called faults 29. Define the following, focus, epicentre, seismic waves? o Focus: it is the point within the Earth where the earthquake starts. It is also called the Hypocenter o Epicenter: It is the location on the surface directly above the focus. o Seismic Wave: It is the energy released when a fault ruptures, causing a vibration of earth. 30. Identify the various forms seismic waves spread from the focus? o Compression waves, exactly like sound waves (P waves) o Shear waves, like waves in a shaken jump-rope (S waves) o Surface waves resembling water waves. 31. The study of seismic waves related to earthquakes is called..? o Seismology 32. Scientists who study seismic waves produced by earthquakes are called..? o Seismologists 33. Which wave travels very slow but causes majority of damage associated with earthquake disasters? o Surface waves 34. An instrument used to detect seismic waves is called? o Seismometer 35. What is a seismograph? o A seismometer is a recording device that produce a permanent record of seismic waves or earth motion 36. What is a seismogram? o A paper record of seismic waves 37. On what bases are the size of an earthquake measured? o Intensity

5 o Magnitude 38. classifies the degree of shaking and. Is a measure of the amount of energy released? o Intensity o Magnitude 39. What scale is used to measure the intensity of an earthquake? o 12-point Mercalli scale 40. The intensity of an earthquake is determined based on subjective observation of destruction, true or false? o True 41. Earthquakes that occur beneath the sea and along the sea and along the coastal areas can generate.? o Tsunamis 42. How is the magnitude of an earthquake measured? o Richter Scale 43. A fault in motion is called a.? o Slip 44. Horizontal offset is called a. and a vertical offset is called.? o Throw & heave 45. The destruction caused by ground shaking during an earthquake at a specific location depends on a number of factors, name three? o The total amount of energy released o The distance from the epicentre o The type of rock and the degree of consolidation 46. What is soil liquefaction? o It occurs when intensity of an earthquake (shaking) turns solid ground into mud. 47. Differentiate between inter-plate and intra-plate earthquakes? o Inter-plate earthquakes occur along tectonic plate boundaries (As explained by the plate tectonic theory) o Intra-plate earthquakes occur at rather large distance from the respective plate margins (Its causation is still not accurately known)

6 Session Four (4) 48. Earthquakes that occur in Ghana are inter-plate earthquakes, true or false? o False 49. Name three active faults in Ghana long which all the earthquake activities in Ghana can be associated with? o Cote d Ivoire fault o Akuapim Fault zone o Coastal Boundary fault 50. Name three areas in Ghana susceptible to earthquake hazard and risk? o Anywhere along the Akuapim-Togo ranges (Along the Akuapim fault zone) o Out to sea along the entire coastline of Ghana (along the coastline boundary fault and the cote d Ivoire fault) o The intersection of coastal boundary fault and the Akuapim fault zone (near Accra in the area between Weija and Nyanyanu on the coast)

7 Session What is a volcano? o An opening/fissure or vent linked with the interior of the earth interior from which molten lava, rock fragments, ashes, dust and gases are ejected. o The mountain or hill formed by the eruptive lava/debris is also often called a volcano. 52. What is volcanism? o It is the eruption of materials from deep within the earth. 53. Differentiate between magma and a lava? o Magma refers to any hot, mobile material within the earth and lava is any hot molten rock (magma) when extruded onto the earth surface. 54. Identify three types of materials erupted from a volcano? o Lava o Rock fragments o Gas 55. Identify two factors that determine the violence of an eruption? o Composition o Temperature of the magma o Dissolved gases in the magma 56. Viscosity of magma increases with increasing.. and decreases with increasing of the magma? o Silica content o Temperature 57. Between a fluid magma and a viscous magma, which one produces an eruptive violence? Why? o Viscous magma o Because gases do not escape easily from viscous magma unlike fluid magma where gases easily escape. 58. What is a tephra and what are they formed from? o They are generally rock fragments including volcanic dust, volcanic ash and volcanic bombs o They are formed from viscous magma is the name given to particles produced in volcanic eruptions? o Pyroclastic 60. Gas gives magma their explosive character, true or false? o True

8 61. Volcanoes that occur within plates are referred to as.? o Hot-spot volcanoes 62. Volcanoes that occur along convergent plates are referred to as.? o Subduction-zone volcanoes 63. Volcanoes that occur along separating plates are referred to as.? o Rift volcanoes 64. List three (3) primary effects of volcanoes? o Formation of eruption columns and clouds o Lava flows destroying properties in their path as they flow. o Emission of poisonous gases. 65. List four (4) secondary or tertiary effects of volcanoes? o Mudflows o Flooding o Tsunami o Volcanic earthquakes and tremors o Atmospheric effects o Famine and disease 66. List three benefits of volcanoes? o Helps renew soil and soils around active volcanoes are some of the richest on earth o Hydrothermal processes associated with volcanism produce rich ore deposits o Heat rising around magma bodies can sometimes be tapped to produce geothermal energy. 67. List four gases emitted by volcanoes that are poisonous to living organisms? Hydrogen Chloride (HCL) Hydrogen Sulphide (H 2 S) Sulphur Dioxide (SO 2 ) Hydrogen Fluoride (HF) Carbon monoxide (CO) 68. State two destructive effects caused by pyroclastic material such as tephra that accompanies volcanic eruption? Destruction of vegetation, including crops Can cause death by suffocation

9 Loss of agricultural activity 69. Identify three forces involved in mass wasting Gravity (perpendicular) Shearing stress (Tangential component of gravity) Friction 70. List four factors that influence slope stability and mass wasting Nature of materials Fluid/water content Vegetation Earthquake Slope gradient Human activities 71. Identify two slow mass movement processes Creep Solifluction 72. Identify three rapid mass movement processes Fall Slide Flow 73. Mass movement are classified on the basis of three features. Name them/. Type of movement Rate of movement Type of materials involved 74. Identify the two broad classification of mass wasting? Slope failures (fall, slides, slump) Sediment flow (creep, earthflows, mudflows, debris avalanche, solifluction) 75. Differentiate between granular flows and slurry flows? Granular flows is a sediment flow that contains between 0 and 20% water. Eg. Creep, earthflow, debris avalanche Slurry flows is a sediment flows that contain between 20% and 40% water. Eg. Solifluction, debris flows and mudflows. 76. Identify three hazards associated with mass movement? Destruction of crops Damage to buildings, roads, railways etc. Loss of life and property Flooding

10 77. Identify three possible preventive measures of mass movements Slope reduction Retention structures Fluid removal