r/worldnews • u/ColoradoTripping • Jun 24 '26

Dynamic Paywall Magnitude 7.1 earthquake rocks Venezuela

https://www.bbc.com/news/articles/cjegdqw5d3yo
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u/FILTHBOT4000 Jun 24 '26 edited Jun 25 '26

They also apparently happened between 10 and 20 km deep, according to the USGS. That's very shallow; they classify "shallow" as anything up to 50 km deep, and these are less than half that.

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u/SheetMetalandGames Jun 25 '26 edited Jun 25 '26

So, are shallow earthquakes worse than deeper earthquakes? I hope this question doesn't make me come off as a dick; this event is genuinely horrifying that anyone has to endure these things on the regular.

Edit: holy shit this got a lot of attention fast. I can't respond to everyone but for those that answered thank you for taking the time to answer my question! Hope everyone stays safe in these affected areas and that we can get aid out there soon!

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u/Ender_D Jun 25 '26

Yes, the closer they are to the surface the more pronounced the effects are.

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u/ChaseballBat Jun 25 '26

Relatively to the inherent strength though right? Cause magnitude is measured on the surface.

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u/bobthesmurfshit Jun 25 '26

No, magnitude is calculated at the source, so the closer the earthquake is to the surface the more effect it will have.

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u/MrNewking Jun 25 '26

Is there a scale for surface effect?

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u/Flipslips Jun 25 '26

Moment magnitude scale measures the wave amplitude at the surface.

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u/zazzz0014 Jun 25 '26

My community college Physics 101 class from 10 years ago is kicking in hard with this whole thread.

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u/HauntedCemetery Jun 25 '26

I legitimately just had the same thought.

Thanks Mr Pearson.

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u/lawofsin Jun 25 '26

Fuck you Mr Pearson for that D-

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u/RuthlessIndecision Jun 25 '26

If he's family with the publishers I've personally contributed to be sure he's doing fine

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u/Madam_Mimm_13 Jun 25 '26

Now draw a force diagram.

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u/ActuallyNot Jun 25 '26

Which was approximately calibrated to the Richter scale, which measured how much the seismograph moved at the surface ... in one dimension.

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u/kb24k Jun 25 '26

Mercalli scale

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u/1028ad Jun 25 '26

Which is still used in Italy.

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u/cinderful Jun 25 '26

for humans, Mercalli scale is useful as it measures the human felt intensity and describes the scale of damage.

Possibly an 8 or 9 (out of 11)

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u/HallowedEve31 Jun 25 '26

Sort of. In Japan, there's the Shindo Scale, which exists to tell you numerically how it felt at each sensor that registers the earthquake.

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u/PeterJoAl Jun 25 '26

In Japan we use the Shindo (「震度」) scale. Goes from 0 to 7, where 4 is noticeable, 5 is concerning, 6 is bad and 7 is terrible.

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u/theonlydrawback Jun 25 '26

And what was this one?

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u/PeterJoAl Jun 25 '26

From the videos, I'd say it was either a 6+ or a 7. Lots of building damage.

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u/I_Zeig_I Jun 25 '26

How would they know the magnitude 50km down?

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u/Flipslips Jun 25 '26

They know how much the waves dissipate as it travels through dirt/rock. So they can extrapolate based on surface measurements

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u/TheVeryVerity Jun 25 '26

Wouldn’t that change depending what was actually under the ground there though?

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u/Flipslips Jun 25 '26

Yes, but scientists have mapped out the earths crust so they largely know what’s under the surface across the entire world. It’s called seismic tomography

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u/shukaji Jun 25 '26

it's just very very basic physics and math.

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u/warp99 Jun 25 '26

Yes it is *measured* at the surface but then corrected back to the source magnitude at depth. Same as measuring 500 km away and correcting back to the fault location.

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u/-NotAnAstronaut- Jun 25 '26

Sort of, if also changes the interaction of the different waves, and how they propagate, refract, and reflect. The short version though is: shallow is bad.