Earthquake in Delhi-NCR, Bihar: What’s a shallow earthquake that struck Delhi?

Nationwide Heart for Seismology stated the earthquake struck at a focal depth of 5 kilometres in Delhi-NCR on February 17, 2025
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Robust tremors had been felt within the nationwide capital and adjoining areas as an earthquake of 4.0 magnitude struck the area early on Monday (February 17, 2025). The Nationwide Heart for Seismology stated the earthquake struck at a focal depth of 5 kilometres at 5:36 am.

After Delhi, NCR, tremor felt in Bihar additionally at 4.0 magnitude. The Nationwide Heart for Seismology stated the earthquake struck at a depth of 10 kilometres at 8:02 am.

Shallow earthquakes, originating 5 or 10 kilometres beneath the floor, are inclined to trigger extra harm than these originating deep beneath the floor.

Shallow earthquakes are between 0 to 70 km deep; intermediate earthquakes, 70 to 300 km deep; and deep earthquakes, 300 to 700 km deep.

An occasion of the devastating impact of a shallow earthquake can be the 5.6 magnitude earthquake in Indonesia in Novermber 2022 that left greater than 160 useless and a whole lot injured as buildings crumbled and terrified residents ran for his or her lives on the primary island of Java.

In keeping with the U.S. Geological Survey, “There may be not one magnitude above which harm will happen. It will depend on different variables, equivalent to the space from the earthquake, what kind of soil you might be on, constructing building” and different components.

Why an earthquake’s depth issues?

A quake’s damaging power relies upon not solely on its power, but additionally on location, distance from the epicentre and depth.

Quakes can strike close to the floor or deep throughout the Earth. Most quakes happen at shallow depths, in keeping with the U.S. Geological Survey.

Shallow quakes usually are typically extra damaging than deeper quakes. Seismic waves from deep quakes should journey farther to the floor, dropping power alongside the way in which.

Shaking is extra intense from quakes that hit near the floor like setting off “a bomb straight underneath a metropolis,” stated Susan Hough, a USGS seismologist.

Commenting on the tremor felt in Delhi-NCR area, Nationwide Centre for Seismology Director OP Mishra says, “Seismologically, it isn’t new area, earthquakes have occurred earlier within the area. Earlier, there was 4.6 magnitude earthquake in 6 km periphery, nevertheless it was deeper, with 10 km depth. There’s a distinction. It was not a plate tectonic earthquake, it was as a result of in situ materials heterogeneity, it was as a result of native impact. We are able to count on aftershock of round 1 or 1.2 magnitude.”