7.2 earthquake in Tonga

Hey good folks – the USGS reported a 7.2 quake off the coast of Tonga, June 15th at 18:06:27 UTC. Thanks to @sheeny’s awesome reporting software, I was able to find this on my Shake 1D (RAF36):

It’s also fascinating to see how obvious this is with the global filter on in stationview:

Looking at that, I’m amazed to think that we’re seeing the Earth ringing. I knew intellectually that this happened, but seeing the evidence is mind-blowing.

Thanks again to @sheeny for the software!

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A large event indeed, instrumentally felt all over the planet, also by RaspberryShake! These are my plots for my location, and for Scotland:

Having the capability to capture events more than 16000 km away with waves that literally cross the insides of the Earth will never stop being fascinating for me.

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I do admire your work Stormchaser! Nice reports!

Your Power Spectra plot, is very different to what I achieve using the PSD function. Obviously, more for me to learn there ;o). Your result is more like what I’m used to seeing on a vibration analyser spectrum plot. Is it from the PSD function or some other FFT function?

FWIW Here’s some of the clearer arrivals from the latest version of my code (refer to GitHub - sheeny72/RPiSandB: Python programs for Raspberry Shake and Boom seismometers and infrasound detectors.):



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As I do with your reports! I particularly love the Specific Energy and the Velocity Frequency plots.

Yes, you are correct. My Power Spectra is calculated via FFT function, this one in particular numpy.fft.rfft — NumPy v1.25 Manual together with numpy.linspace — NumPy v1.25 Manual

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Thanks Stormchaser.

When I get some time I’ll have to investigate and experiment! ;o)

Al.

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Always welcome sheeny!