Tectonic
Processes
and Hazards
Enquiry Question 3: How successful is the management of
tectonic hazards and disasters?
,1.7 Understanding the complex trends and patterns for tectonic disasters helps explain
differential impacts.
Tectonic Disaster Trends
It is estimated that in the 20th century, only 2.2% of human fatalities from natural
disasters were the result of earthquakes and their secondary hazards. Volcanic
eruptions were only responsible for 0.1%.
The majority of fatalities were due to slow onset natural events, such as draught and
famine, rather than rapid onset natural events, such as earthquakes.
Most disasters result from the complex interactions between humans and natural
disasters. For example, poverty may force people to live in risky areas (steep slopes,
eg: Mount Merapi, Indonesia) or economic opportunities and wealth may encourage
people to move to risk areas voluntarily (eg: California transform fault zone).
A key vulnerably factor is lack of education in hazard zones or after a hazard event,
relief and aid may not be evenly distributed.
Poor infrastructure and services (eg: healthcare) may make a disaster worse, as aid
cannot be distributed, eg: Kashmir earthquake 2005, and secondary impacts, such as
disease, eg: cholera in Haiti.
Jobs may be lost, crops and livestock destroyed, or areas become uninhabitable for a
period of time, eg: radioactivity at Fukushima following the Tohoku 2011 tsunami.
Recorded Earthquakes from 1973 - 2006 - Why?
More people are living on plate boundaries, eg: San Andreas Fault, California and a
larger population worldwide so people living on remote islands can report them.
Increased frequency of earthquakes.
Better communication technology so more get reported.
Media coverage has increased, so more are being recorded.
Better detection (seismometers) even in isolated areas.
Fracking for shale gas increased earthquakes.
, Increase in earthquakes since 1900.
Earthquake deaths fluctuate.
Some years are less than 1,000 deaths (2000, 2007, 2012) but some are over 300,000
(Haiti 2010). These single mega-disasters increase earthquake deaths and often
distort trends by skewing the figures.
Disaster deaths are sometimes under recorded for political reasons.
There should be a decrease in earthquake deaths globally, due to better education,
better building design, land use zoning and better rescue and relief.
Increased impacts economically over time, due to increased urbanisation,
industrialisation and wealth in emerging countries (China, India).
More buildings, increased infrastructure, schools, power stations, roads, bridges,
power lines.
Increased wealth of individuals through property/possessions.
Economic costs highest for mega-disasters (Japan tsunami).
