|Describe a Destructive plate margin.
|Oceanic and continental plates move together due to convection currents. oceanic plate is forced under the less dense continental plate. Rock melts forming magma, which rises to create a volcano.
|Describe a Constructive plate margin. (Divergent plate margin)
|Plates move apart due to convection currents, magma rises up forming a new crust. Examples: Mid- Atlantic ridge.
|Describe a Collision plate margin.
|Collision zones form when two continental plates collide. Neither plate is forced under the other, therefore both plates are forced up to form mountains.
|Describe a Conservative plate margin.
|Plates slide past each other in opposite directions or in the same direction at different speeds. Friction builds causing earthquakes. Examples: San Andreas fault - California.
|What's the difference between Continental crust and Oceanic crust?
|Continental layer is 30-50 Km below ground, density of 2.7 g/cm3, its solid rock made up of granite and it 900 degrees C. Oceanic layer is 6-8 Km below ground, density of 3.3 g/cm3, its solid rock, made of basalt, its 900 degrees C.
|Briefly explain a convection current.
|The solid inner core radiates heat creating a convection current. A plume of hear rises towards the surface of the earth but as it cools it moves along the plate before cooling fully and sinking back towards the inner core. The process is then repeated.
|What are the differences between a Shield-volcano and a Strato-volcano?
|Shield-volcano has ballistic lava that flows far whereas Strato-volcano have this viscous lava that clogs up the vent. Shield found at constructive plate boundaries and Strato found at destructive plate boundaries. Shield eruptions are non violent but Strato are violent and unpredictable. Shield: Sturtsy, Iceland. Strato: Sakajimo, Japan.
|What is a primary effect?
|The immediate impacts of an event, eg. Gas pipe breaks.
|What is a secondary effect?
|The events that will only happen because of the primary impacts, eg. Fire occurs due to gas leak.
|Merapi case study: List 4 social effects from the eruption.
|Primary: buildings were deemed unsafe. People were burnt. Secondary: 400,000 people were evacuated. Over 300 people died.
|Merapi case study: List 3 environmental effects from the eruption.
|Secondary: Farmland damaged due to the large amounts of ask from ash clouds. Acid rain caused due to gasses released. Livestock died due to lack of food and clean water.
|Merapi case study: List 2 economic effects from the eruption.
|Secondary: Loss of businesses due to damage to buildings and stock. Costly health care due to the injuries sustained.
|list 6 facts of the New Zealand earthquake in Christchurch.
|181 deaths. 2,000 injured. 1,000 homeless. liquefaction caused damage to roads and buildings. People needed mental support. Insurance companies payed $898 in building claims.
|List 7 facts about the Haiti earthquake.
|230,000 deaths. 300,000 injured. 1 Million homeless. Half of AID spent on building homes and shops. 1 in every 15 died. Only half of the airport was functioning therefore no access for AID. Infected river caused Cholera -6,000 deaths 2 years after incident.
|list 5 ways to predict earthquakes and volcanoes.
|Aircraft's: Measure the amount of gas given off by volcano. Tilt-Meters: Detect when volcano fills up with magma. Bore-Holes: Measure the water temperature as magma rises it heats up. Hot-Springs: are monitored in same way as Bore-Holes. Seismometers: monitor earthquakes from inside the volcano.
|List 5 defenses against volcanic eruptions and earthquakes.
|Dam it: by creating walls of rock and earth to stop pyroclastic flow. Blast it; by dropping bombs onto lava flows and dropping concrete blocks into hole. Dig it: by digging pathways fro lava flow away from populated areas. Spray it: To cool lava and form rocks.