The earthquake that occurred during the commuting time for work and school sent the large city of Osaka into turmoil on Monday.
The earthquake had a maximum seismic intensity of lower 6, mainly affecting northern Osaka Prefecture. It was the first time Osaka had been directly shaken that strongly since seismic records were first kept in 1923.
It has been confirmed that four people died in the quake, including a 9-year-old girl who was caught under a concrete block wall that collapsed. Damage was caused in various places – houses and other buildings were destroyed, fires broke out one after another and many people were injured.
Railways, expressways and other transport networks were temporarily paralysed over a wide area, preventing a vast number of people from moving to different locations for long hours. Lifts were suspended in many high-rise buildings and condominiums.
The latest quake has shown how significant damage can be caused by a quake with its focus just below an urban area.
The quake has damaged and halted gas, water supply and other lifeline systems, hindering the lives of people in disaster-stricken areas. The Government has set up a disaster-response office at its crisis management centre at the Prime Minister’s Office.
The latest earthquake occurred when a fault just below the urban area moved. Multiple active faults have been confirmed to exist in the area surrounding the quake’s focus, including the Arima-Takatsuki fault zone.
There are risks the latest earthquake will trigger another quake. Precautions for such and event cannot be neglected.
Damaged houses and other buildings may yet collapse. The quake has made the ground unstable under sloping land. Local governments should urge residents in risky locations to evacuate. Taking temporary refuge at evacuation sites helps protect lives.
There may be a decline in the strength of concrete block walls that did not collapse in the quake, so it is advisable for people in the area not to approach them until their safety is confirmed.
Some companies have been forced to suspend operations because their employees cannot get to work, and t he Government has urged all companies to put together business continuity plans in preparation for major disasters. Although 60 per cent of large companies have completed this task, according to the Cabinet Office, only 30 per cent of midsize companies have devised such plans.
There are also concerns about the possible occurrence of an earthquake with its focus immediately below Tokyo. Although there had been no major earthquake in Gunma Prefecture for a long time, a quake with the intensity of lower 5 happened on Sunday. In Chiba Prefecture, there was what is called a “slow slip”, a large-scale underground phenomenon that could trigger an earthquake swarm.
In an area stretching from waters off the Tokai region to Kyushu, precautions are needed for a massive earthquake expected to occur with its focus originating in the Nankai Trough.
A massive earthquake can occur anywhere. This should be taken to heart.