Unit 1: Section A: Tectonic Hazards Flashcards
What are the three types of plate margins?
Destructive, constructive and conservative
What does a destructive margin involve between an oceanic plate and a continental plate?
In involves an oceanic plate subducting beneath a continental plate which is denser creating gas-rich magma
What does a destructive margin involve between a continental plate and another continental plate?
The ground is folded upwards creating fold mountains
What does a constructive margin involve?
Where two plates are moving away from each other, magma rises from the mantle to fill the gap and cools creating new crust
What does a conservative margin involve?
Where two plates are moving sideways past each other, or in the same direction at different speeds and crust isn’t created or destroyed
Which plate margins can volcanoes form at?
Destructive and constructive
Which plate margins can earthquakes form at?
All of the plate margins
How are volcanoes formed at destructive plate margins?
The denser oceanic plate moves down into the mantle where it melts, a pool of magma is formed which then rises through cracks in the crust. The magma erupts forming a volcano
How are volcanoes formed at constructive plate margins?
The magma rises up into the gap created by the plates moving apart, forming a volcano
How are earthquakes caused at destructive plate margins?
Tension builds when on plate gets stuck as it moves past the other
How are earthquakes caused at constructive plate margins?
Tension builds along cracks in the plates as they move away from each other
How are earthquakes caused at conservative plate margins?
Tension builds up when plates that are grinding past each other get stuck
What are the two earthquake case studies you need to know?
Chile 2010
Nepal 2015
What were three primary effects of the Chile 2010 earthquake?
- 500 deaths, 12000 injured
- Disrupted power, water supplies and communications
- Santiago Airport and the port were severely damaged
What were three secondary effects of the Chile 2010 earthquake?
- Tsunami waves devastated coastal towns
- Fires at chemical plant which led to evacuation in the area
- Landslides destroyed 1500 km of road, cutting of remote communities
What were three immediate responses to the Chile 2010 earthquake?
- $60 million raised funding emergency shelters
- International support provided field hospitals, satellite phones and floating bridges
- The north-south highway was temporarily repaired to allow transportation of aid
What were three long-term responses to the Chile 2010 earthquake?
- Government launched housing reconstruction plan helping around 200,000 families
- Chile’s strong economy reduced the need for foreign aid
- Recovery took over 4 years
What were three primary effects of the Nepal 2015 earthquake?
- 9000 deaths, 22000 injured
- 4 million left homeless
- Water tanks destroyed leaving 2 million without clean water and sanitation
What were three secondary effects of the Nepal 2015 earthquake?
- Avalanches triggered killing 18 people
- Mountain roads blocked by landslides preventing aid from reaching remote areas
- Lack of clean water lead to typhus outbreak killing 13 people
What were three immediate responses to the Nepal 2015 earthquake?
- India and China sent teams to save trapped people under debris
- Charities provided medicine, food and water supplies
- Red cross set up emergency shelters for 130,000 families
What were three long-term responses to the Nepal 2015 earthquake?
- World bank funded $500 million towards projects aimed at building earthquake-resistant infrastructure
- Heritage sites reopened to encourage more tourists to visit again
- Main roads reopened 2 years after the disaster
What are 3 reasons people still choose to live in areas at risk from tectonic hazards?
- Minerals from volcanic ash makes nearby soil very fertile attracting farmers
- They’re confident that their government will financially support them
- Provides jobs in the tourist industry
What are the 4 management strategies used to reduce the effects of tectonic hazards?
Monitoring
Prediction
Planning
Protection
What does monitoring tectonic hazards involve?
Scientists use data and equipment in order to keep an eye on tectonic patterns
