When an earthquake hits, the ground shakes, which can cause serious damage. But earthquakes also generate other destructive effects.  

Surface rupture: The ground breaks, which can cause damage to roads, railways and communication lines.  

Liquefaction: When seismic waves shake water-saturated sediments, the soil and rock can lose its solid properties and behave like a fluid. Building foundations sink and move, causing building damage and even destruction.  

Landslides: Loose sediments on slopes and even hard rock on steep mountains can become unstable and slide when the earth shakes.  

Tsunami: These waves can be generated when an earthquake occurs under the ocean or close to the coast. Today, most coastal cities around the world have tsunami early-warning systems which aim to give coastal populations some time to reach safety before tsunami waves hit land. These systems rely on information provided by seismic waves—which travel about thirty times faster than tsunami waves—and ocean buoys that measure sea height. The further away the epicentre is from land, the earlier warnings will be issued, helping people reach safety in time.  

Flooding and fire: Earthquakes can cause structural damage to dams and, in turn, cause floods. They can also damage natural gas pipelines and power lines, causing fires.  

Aftershocks: These smaller and shorter earthquakes can cause the collapse of structures that were damaged but not destroyed by the main, stronger earthquake.  

Maximum tsunami wave height (colored background) and travel time (contours in hours) computed for one of the credible sources for the 1st November 1755 event (IPMA).

When the fault that ruptures during an earthquake reaches the surface, the ground breaks, causing a surface rupture, which can cause damage to roads, railways and communication lines.

When seismic waves shake water-saturated sediments, the soil and rock can lose its solid properties and behave like a fluid, in a process known as liquefaction. Building foundations sink and move, causing building damage and even destruction.

Loose sediments on slopes and even hard rock on steep mountains can become unstable and slide when the earth shakes.

Earthquakes sometimes cause the ground to permanently subside, originating floods, as was the case during the 2011 Tohoku earthquake in Japan.

Fire in Central Kobe after the 1995 Kobe earthquake in Japan. Earthquakes can cause structural damage, including damage to natural gas pipelines and power lines, causing fires.

A mainshock is the highest magnitude earthquake in a seismic crisis, that is, in a period of enhanced seismic activity. All the earthquakes in the crisis that occur before and after the mainshock are called, respectively, foreshocks and aftershocks. Even though aftershocks are smaller and shorter than the mainshock, they can cause the collapse of structures that were damaged but not destroyed by the main, stronger earthquake.