
Explained: Why are earthquakes so hard to predict?
People in B.C. regularly have earthquake drills at school and work, trying to prepare for what’s known as “the big one.”
The problem is, it is almost impossible to predict when that will happen.
Why don't we know when the next big earthquake will hit? There's an explanation for that.
Unpredictable plate movement
Tectonic plates are, like most of us, under a lot of stress and are always in motion.
But they move slowly, and the exact moment when the stress between them will be released is uncertain.
While scientists can measure stress building up along fault lines, it’s impossible to know exactly when it will trigger an earthquake.
Complex fault systems
We all have our faults, but the Earth’s crust is full of them. Some might be hidden or have complicated relationships with other nearby faults, making it harder to predict where the stress will be released first.
Lack of warning signs
Unlike weather events, which often show signs beforehand (like wind picking up or clouds forming before a storm) earthquakes don’t have clear, consistent early signals.
Though small tremors, called foreshocks, can sometimes happen before a larger quake, they are unreliable and don’t always occur.
Seismic waves travel quickly
Once an earthquake starts, the seismic waves travel through the ground quickly. This means even if scientists detect the first tremors, they only have seconds to warn people in nearby areas, and it’s too late to predict it in advance.
Limited technology
While scientists have developed ways to monitor fault lines and seismic activity, current technology can’t measure the exact conditions deep underground where earthquakes start.
This makes it hard to gather enough detailed information to predict when and where the next earthquake will happen.
Scientists are making progress in understanding earthquake patterns and using early-warning systems, but predicting the exact time and location of an earthquake remains a significant challenge.
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Header image: File photos/Canva Pro/Cheryl Santa Maria.