Reasons for the particularly severe earthquake and
tsunami disasters in Indonesia
(1)Large earthquake magnitude and shallow hypocenter
The earthquake was a major one. Earthquake occurred at the
junction of the Australian plate and the Indian Ocean plate,
which were global tectonic plates. In the seismic area, the
Indian Ocean plate, relative to the Myanmar Plate, moved
northwest at a velocity of 6 cm/a and convergence of oblique
subduction in the Sunda Trough. The long-term subduction of
the Indian Ocean plate beneath the Myanmar plate accumulated
tremendous stress and energy, which suddenly released and
caused violent shaking of the earth's crust.
Because of the shallow hypocenter (only 10 km), the strong
disturbance to the sea water caused a huge tsunami.
(2)There was no tsunami warning system and no early warning
mechanism in the affected areas.
Neither country in the Indian Ocean had established a tsunami
warning system and lacked an early warning mechanism，when a
major earthquake triggered a tsunami, the local government and
people suffered the disaster of "toppling" without any knowledge
of prevention and refuge. In order to prevent the tsunami, many
countries in the Pacific Ocean had established the Pacific
Tsunami Warning System as early as the 1960s, the International
Oceanographic Commission had formed ‘‘the International Coordination
Group for the Pacific Tsunami Warning System.’’ Coordination of
tsunami warning system operations had been carried out and there
had been some successful tsunami warnings, thus greatly reducing
casualties in the event of tsunami.
(3)Potential risk of earthquake and tsunami in disaster-stricken
areas was underestimated.
Although the earthquake and tsunami had been recorded in the
history of the countries , it was not enough to estimate such a
large disaster and to cooperate actively with international
tsunami research institutes and countries with early warning
(4)Insufficient social preparedness for disaster prevention
in disaster-stricken areas.
Some disaster-stricken areas were underdeveloped and coastal
buildings lacked corresponding anti-tsunami measures, some
public buildings such as tourism and vacation on the seashore
lacked of wave-proof and safe-haven facilities, no good disaster
preparedness in advance.
In addition, transportation and communication facilities were
backward. after the disaster , disaster situation could not be
transmitted in time, delaying the post-disaster relief work and
objectively aggravating the disaster degree.
(5) Disaster-stricken areas were in the tourism-peak season,
weak awareness of disaster prevention.
The earthquake and tsunami took place at Christmas this year,
which was the tourism-peak season in the disaster-stricken areas,
tourists from all over the world gathered at the seaside, the
occupancy rate of hotels had reached 100%, tourists were in a
relaxed and leisure state, local people were busy receiving,
awareness of disaster prevention is very low.