What happens after an earthquake – engineers answer FAQs

On Wednesday 24 June 2026, two earthquakes struck Venezuela less than a minute apart (at around 6pm local time).

Registering in at a magnitude of 7.2 and 7.5, the latter was the strongest to hit the country in over 100 years.

The earthquakes were shallow, at less than 30km underground, which can cause more damage as the shock waves have more energy when they reach the surface.

At least 920 people have died, and over 3,300 have been injured.

Why do buildings collapse during earthquakes?

The shaking from an earthquake is transferred from the ground to structures built on top.

Those that have not been designed with the required ductility or flexibility, could suffer harm or even collapse.

Damage could range from superficial cracks in non-loadbearing components of the buildings to more serious fractures. In reinforced concrete buildings, columns can buckle under the excessive forces of earthquakes if they aren't designed appropriately.

It can lead to complete collapses when critical joints between vertical and horizontal members of a building fail.

What does an earthquake emergency response consist of?

The most important aspect of an early emergency response is to identify where the trapped and injured may be within the affected area and try to help.

There are international search and rescue teams ready and able to help local authorities to administer these efforts.

A UN-classified urban search and rescue (USAR) team, such as SARAID, will not deploy unless they receive a request for assistance, either via the UN or directly via responsible officials.

These efforts must be coordinated by local emergency managers so that help is welcomed, not an added burden on the already stretched system. And, to make sure aid is distributed in the most effective way possible.

How can engineers help with the emergency response?

There will be many people who will be displaced after an earthquake.

Engineering expertise is required to provide support in identifying locations for camps, setting up temporary shelters, establishing water and sanitation supplies, and coordinating logistics.

Engineers will also be deployed to assess damage at specific essential services facilities, key transports links including the railway and airports, as well as a more general damage assessment.

Can buildings be earthquake-proof? And are there building codes that guide this?

Buildings can be designed to resist earthquake loads, but there will always be some risk of significant damage or collapse. In seismically vulnerable countries, earthquake-resistant designs are part of the building codes and design guidance.

The level of requirements would depend on the location of the building, the underlying soil conditions, and the acceptable level of risk to the building.

Some critical facilities like nuclear power stations would have a much stricter design criteria than single house dwellings, for example.

Is it possible to retrofit existing buildings to be earthquake-proof?

Yes, there are many examples around the world of retrofitting old heritage buildings and those that were designed before building codes were developed.

This can be done by introducing strengthening elements, such the addition of shear walls, or wall anchors.

What other types of infrastructure are likely to be affected by earthquakes?

In effect, anything that stands in the way of the path of the energy that spreads out during an earthquake, whether it’s the natural or built environment.

There are different methods of making infrastructure earthquake-proof, and again the proposed approach would depend on the location, its context, and underlying soil conditions.

What’s the process of rebuilding after an earthquake?

Rebuilding after an earthquake takes time.

Depending on the size of the event and the location of the earthquake, the severity and the geographical extent of the damage would vary.

For catastrophic events, the earthquake would leave hundreds of thousands of people homeless and in desperate need for shelter and housing. Not to mention repairs to utilities and critical infrastructure.

To put things in perspective, the UK builds around 200,000 homes a year.

One of the key requirements of rebuilding is in balancing speed vs deliberation. There is no magic formula, but public consultation and strong governance can lead to a successful outcome.

How are earthquakes measured?

Earthquakes are measured in terms of the amount of energy they release.

Scientists typically measure an earthquake’s ‘size’ using the moment magnitude scale, instead of the older but more renowned Richter scale.

Moment magnitude numbers scale such that the energy release increases by a factor of approximately 32 for each whole magnitude number.

Watch the animation to learn more.

Insights from previous earthquakes