PORT-OLRY, Vanuatu, July 24 — A magnitude 5 earthquake struck about 96 kilometers north-northwest of this coastal town Friday, the U.S. Geological Survey reported. The quake hit at 23:44 UTC at a depth of 10 kilometers. No tsunami warning was issued.
What does that shallow depth mean in practical terms? Think of it like this: a shallow earthquake is akin to a heavy book dropped on a table right next to you — the jolt is immediate and sharp. A deeper quake of the same magnitude is more like that same book dropped from the floor below — you still feel it, but the sensation is a duller rumble. The USGS notes that shallow events less than 70 kilometers deep typically produce stronger shaking at the surface than deeper ones of the same magnitude. At just 10 kilometers, this one is decidedly in the “sharp jolt” category.
A magnitude 5 earthquake falls into the moderate range. It can cause minor to moderate damage near the epicenter, particularly in areas with less resilient construction. The practical upshot for people in the affected area: expect some rattling, possibly cracked walls or fallen objects, but not the kind of widespread destruction that larger quakes can produce.
Vanuatu sits in a seismically active neighborhood. According to the USGS, at least 500 earthquakes of magnitude 5.0 or greater have been recorded within about 300 kilometers of this spot over the past two decades. The strongest during that window was a magnitude 7.8 in 2009 — a far more powerful event that would have produced much more intense shaking and potential damage.
The USGS detected this earthquake through its real-time global seismic monitoring network. That network uses seismometers around the world to pinpoint the location, depth, and magnitude of earthquakes within minutes. For this event, the agency had enough data to confirm the shallow depth and moderate size quickly.
Seismologists note that aftershocks are common after an earthquake of this size. While it’s impossible to predict exactly when or where a specific aftershock will occur, smaller tremors may continue for days or even weeks. People in the Port-Olry area are generally advised to be prepared for further shaking — a reminder that the ground often doesn’t settle all at once after a jolt of this magnitude.
For now, the event appears to have been a moderate, shallow shake in a region that sees many such earthquakes. The absence of a tsunami alert is consistent with an earthquake of this size and depth; magnitude 5 events, even shallow ones, rarely displace enough seafloor to generate a dangerous wave. The key takeaway for anyone nearby: it was a solid jolt, but not an extraordinary one by local standards.
