3.1.1.2 Tectonic Hazards: Living with the Risks of Tectonic Hazards Flashcards
How many people live in seismically active areas?
2015 reported that more than 2.7 billion people live in seismically active areas
How many people live near one of the 220 most dangerous volcanoes?
more than 400 million people live near one of the 220 most dangerous volcanoes
Why do some people live in hazardous areas?
- larger earthquakes and volcanic eruptions don’t happen frequently - not seen as great threats in most people’s lives
- better building design can withstand earthquakes so people may feel less risk
- more effective monitoring of volcanoes and tsunami waves enable many people to receive warnings and evacuate before events happen
- fault lines associated with earthquakes can allow water supplies to reach the surface - important in dry desert regions
- plate margins often coincide with very favourable areas for settlement e.g. coastal areas where ports have developed
- some people may not be aware of the risks of living close to a plate margin
- volcanoes can bring benefits e.g. fertile soils, rocks for building, rich mineral deposits and hot water
Why do people live with the risks of tectonic hazards?
- fertile soils
- minerals
- tourism
- poverty and education
- frequency of tectonic activity
- monitoring and protection from tectonic hazards
How does volcanic activity produce fertile soils and why might this attract people to hazardous areas?
- when volcanoes erupt they emit lots of ash and material into the air which eventually settles into the surrounding slopes and its base
- volcanic soils release valuable minerals and nutrients which enrich the soil as well as improving soil characteristics such as moisture retention
- agriculture is therefore a major source of income for people living in these areas - can make money from growing and selling soils
How does volcanic activity produce fertile soils in Hawaii?
- In tropical areas in particular, for example Hawaii, climate conditions mean that the weathering of lava is fairly quick resulting in the growth of lush vegetation due to the rapid soil formation
- As volcanic areas are ideal for growing crops they attract large populations
How does volcanic activity produce fertile soils in Java?
In Java (Indonesia) some of the best rice growing areas are in the shadow of volcanoes such as Mt Merapi which attract large numbers due to the rich farming opportunities (1 million live within 20 miles of Merapi)
How does volcanic activity produce fertile soils in Italy?
In Italy large numbers live on the slopes of Vesuvius and Etna (one in five Sicilians are believed to live on the slopes of Etna) due to the fertile soils which provide rich opportunities for growing products such as Olives and fruit
How does volcanic activity produce minerals and why might this attract people to hazardous areas?
- Valuable minerals such as Copper, Gold, Silver, Lead, Zinc and even Diamonds are all associated with volcanic areas as they are due to the rising magma which may cool and harden beneath the volcano
- As hot water circulates within the cooled magma, the metals are taken by the water and re-deposited in greater concentrations
- Volcanic areas are therefore excellent areas for mining, creating economic activities through job opportunities and the value of the mined minerals
Where did mineral mining at a volcano in 1892 occur?
Copper, Gold and Silver mining began around Mount St Helens (USA) as early as 1892
How are minerals from volcanic activity in Java used and benefitted from?
- The traditional sulphur miners of East Java bear the scars of their labour - poisoned lungs and skin criss-crossed with burns and scars.
- Several hundred men work in the heart of Ijen volcano in East Java, Indonesia.
- Each day, they collect yellow lumps of sulphur that solidify beside its acidic crater lake.
- Once processed, the sulphur is used to bleach sugar, make matches and fertiliser, and vulcanise rubber in factories at home and abroad
How does tectonic activity cause tourism and why might this attract people to hazardous areas?
- Due to the spectacular scenery associated with volcanic landscapes and unique features such as lava flows and Geysers, volcanoes, particularly those having experienced recent eruptive activity are particularly popular with tourists - this is a huge economic benefit
- Tourism attracts custom for businesses such as hotel, cafes etc. creating jobs and improving the local economy
What is an example of a volcano that receives large amounts of tourism?
Yellowstone National Park in the USA with the famous Old Faithful geyser receives around 3 million visitors a year
How do tectonic hazards in Iceland attract tourists?
- Iceland is famous for its volcanic landscape and its hot springs and geysers have attracted many tourists
- The Blue Lagoon, near Reykjavik is a spa popular with tourists for its known positive effectives on the skin
How might poverty and education cause people to live with the risks of tectonic hazards?
- some people may not have a choice in whether or not they live in a hazardous area - cannot afford to move away
- top priority in less wealthy countries is having an income, food and necessities - the risk of a hazard is a less pressing issue
- lack of education about the risks that tectonic hazards pose to the population - may not be aware about the risk of living with a tectonic hazard and are therefore not concerned
