An earthquake is the shaking and vibration of the Earth caused by underground movement along a fault plane or by volcanic activity. Earthquakes happen without warning.
They range in strength from slight tremors to major shaking, lasting from a few seconds to a few minutes, and may be followed by a series of aftershocks. An aftershock is a smaller earthquake that occurs after a previous, large earthquake, in the same area of the main shock.
A seismograph using the Richter scale measures the energy released known as the Richter magnitude (ML) of an earthquake. The highest ML recorded on this scale is 9.5.
Most earthquake-related injuries and deaths result from falling debris when shocks damage or demolish buildings and other structures. Earthquakes can also cause:
- fires - from ruptured gas lines
- damage to containers holding hazardous materials
- landslides and rock falls
- soil liquefaction.
Australia averages about 80 earthquakes per year with an ML of greater than 3.0. Australia also averages an ML 5.5 every two years, and an ML 6.0 every five years.
Australia's most damaging earthquake occurred at Newcastle NSW in 1989, when an ML 5.6 earthquake resulted in 13 deaths, 150 injuries and $3 billion in damage.
In the event of a severe earthquake, SA Police will be the control agency responsible for managing the emergency response. Such an event is likely to involve a whole-of-government response and recovery effort.
Prepare for an earthquake
Planning and knowing what to do during an earthquake will help you avoid making decisions that could prove fatal. As part of your preparation you should:
- understand your risks from an earthquake
- discuss your plan with household members
- write your plan
- manage your plan
- have an emergency kit
- think about looking after others
- prepare your home
- prepare your business
- prepare your vehicle
- think about sheltering in or leaving your home
- learn what to do during and after an earthquake.
There are simple things you can do around your home and business property to reduce the risk of injury or damage to property damage during an earthquake.
Do a walk-through of your home or business to locate safe places to DROP, COVER, HOLD:
- look for strong tables or desks that can provide shelter from falling debris
- look for places next to an interior wall away from:
- windows that can shatter
- tall furniture and hanging objects that can tip, fall or drop on you
- fire places with chimneys that can topple over and fall through the roof.
Move furniture and items such as bookshelves and pictures and mirrors away from beds, sofas or anywhere you sit or sleep.
Fix potential hazards in your home or business:
- install latches on cupboards
- secure top-heavy furniture and appliances to walls
- keep wall and ceiling fixtures away from where you sleep or sit
- strap water heaters correctly to the wall
- store flammable or hazardous materials on lower shelves or on the floor
- store heavy or fragile items on bottom shelves.
Get qualified advice to make sure your home complies with the Building Code of Australia and fix any potential weaknesses.
Make sure your insurance, covers you for earthquakes.
Quake safe your home - NZ Earthquake Commission
During an earthquake
In an earthquake it's important that you quickly DROP, COVER and HOLD.
DROP to the ground close to you—no more than a few steps or less than two metres away—where your can avoid injury from flying debris.
Take COVER under something strong, like a sturdy table.
HOLD on to it until the shaking stops.
If you are indoors
DROP, COVER AND HOLD.
If indoors, stay there. Wait until the shaking stops and you're sure it's safe to exit.
- If there isn't a table near you, drop down next to an interior wall and anything stable, cover your head and neck with your arms, hold onto the stable item or brace yourself against the wall.
- Don't run outside or to other rooms.
- Keep in mind that in modern homes, doorways are stronger than any other part of the house and doors can swing and injure you.
- Don't use escalators or lifts.
- Stay away from exterior walls, windows, chimneys and anything near you that could fall.
If you're in a crowded area, don't rush for the doors, move clear of overhead fittings and shelves and DROP, COVER and HOLD.
If you're in a lift, DROP, COVER and HOLD. When the shaking stops and it's safe to do so, try to get out at the nearest floor.
If you are outdoors
Move no more than a few steps, away from buildings, trees, streetlights, and powerlines. Then DROP, COVER and HOLD.
Stay outside until the shaking stops and you're sure it's safe to move about.
If you're in a city street, DROP, COVER and HOLD sheltering from falling debris under strong archways or doorways. Don't go under awnings or parapets as they might collapse.
If you're in a vehicle, pull over to an open area, stop and stay there (with your seatbelt on) until the shaking stops. Check your local ABC radio station for warnings before moving. Be aware of damaged roads, fallen powerlines and damaged overpasses and bridges.
If you're at the beach, DROP, COVER and HOLD. Move immediately to higher ground when the shaking stops.
If you are trapped
Don't move about or kick up dust, cover your mouth with a handkerchief or clothing.
Tap on a pipe or wall so rescuers can locate you. Shout only as a last resort so you don't inhale dangerous amounts of dust.
After an earthquake
Expect aftershocks. Each time DROP, COVER and HOLD.
Check for injuries and damage
Check for injuries:
- if a person is bleeding put direct pressure on the wound - use gauze or cloth
- don't move a seriously injured person unless they're in immediate danger
- for life-threatening injuries call Triple Zero (000).
First aid fact sheets - St John Ambulance
Check for damage:
- if the building is severely damaged, get out straightaway
- if possible put out small fires
- if you smell gas or hear a blowing or hissing noise:
- open windows
- get everyone outside
- don't use any electrical appliances as they create a spark
- turn off the gas at the meter or bottle
- if there is electrical damage turn the power off at the mains
- call a qualified electrician or gas fitter to fix faults before turning the gas or power back on
- cover spilt hazardous materials with dirt or absorbent material
- stay away from brick walls and chimneys with visible cracks
- stay away from downed powerlines and objects in contact with them.
Continue to follow your emergency plan
When it's safe:
- help others, including neighbours
- tune into your local ABC radio station. Information may change quickly so check regularly for updates and heed any warnings
- don't overload phone lines with non-emergency calls. I you must use your mobile phone do it with text
- don't drive unless it's an emergency.
In the days following an earthquake: