Author Topic: Seismographs and thunder  (Read 878 times)

0 Members and 1 Guest are viewing this topic.

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1771
    • Weather at Eau Claire, WI
Seismographs and thunder
« on: March 06, 2021, 11:42:56 AM »
I see a lot of interest in earthquakes and many of the display programs get data on the recent activity and publish them with distance, magnitude, depth and so on.

I even saw an aside comment that one participant here was working on his own device to use for monitoring.

My question is, as we approach spring and some very good storm seasons to be had, is whether or not a loud thunder can set off a local seismograph?

I have been around, usually after passage of the main storm, enjoying the storm's lightning and thunder, when every now and then there is a thunder event which literally shakes the house, rattles windows and I swear I can feel the house quiver a bit.  Once it happened while I was standing in the garage on the concrete slab and I certainly thought I saw little ripples in a bucket of water, like tapping on the side.

I know that some universities have vigorously opposed expansion of rail lines and heavy traffic roads near some of their established buildings where that kind of vibration transmitted to the ground would goof up some of their sensitive equipment, so ground shake can certainly be felt and detected.

Has anyone with a home seismograph seen their detector indicate a heavy, rolling nearby thunder event?
Just curious while waiting for one to happen, and no I don't have a seismometer.
Dale
ECWx.info
&
ECWx.info/t/index.php

Offline Yfory

  • Senior Member
  • **
  • Posts: 65
Re: Seismographs and thunder
« Reply #1 on: March 07, 2021, 01:53:58 AM »
DaleReid,

I do not have experience with thunder here - it is very rare. I live north of San Francisco. But...I did build a seismograph and developed it to a high sensitivity.  I was able to measure small seismic events in the 2.0 magnitude range originating about 30 miles from my house. A magnitude 2 is so small most people can not feel the event. A three is something some people can feel depending on the distance to the epicenter and depth of the "quake".

I live about 5 miles from the pacific ocean and 5 miles from the surf which is usually about 5 to 15 feet depending on weather. My seismograph routinely measured the surf of the ocean  - a period of about 7 seconds here. In fact surf noise is a real problem to coastal seismology. Once a good seismograph is in position, it can measure the movement of tree roots in a strong wind.

A comment on DIY seismographs - I would guess the voltage pickup on a routine moving coil design, would be about 1 millivolt down to 10 microvolts, for a typical 5.0 about a 1000 miles from the instrument. But this a very crude estimation on my part.

This information might help answer your question.

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1771
    • Weather at Eau Claire, WI
Re: Seismographs and thunder
« Reply #2 on: March 07, 2021, 08:02:22 AM »
I can see why so many people seem to be interested in seismology.  I had no idea that surf could be a problem, but it makes sense now that  you mention it.

Very interesting.

I am jealous of you being near 5-15' surf, but feel sorry for you not having the thrill of frequent thunderstorms!

Thanks again.
ECWx.info
&
ECWx.info/t/index.php

Offline chief-david

  • Educational Weather
  • Forecaster
  • *****
  • Posts: 2677
  • Space Academy for Educators
    • Benilde-St. Margaret's Weather
Re: Seismographs and thunder
« Reply #3 on: March 07, 2021, 10:44:15 AM »
There is a seismograph at U of Minnesota/Morris. Maybe they have some insight.

In my JH trained experiences---I would not think thunder would trigger it.
Trains, maybe tornados could.  We know football games can.


[youtube]https://youtu.be/w2hOgbq2myA[/youtube]
« Last Edit: March 07, 2021, 10:45:52 AM by chief-david »



You can't phase me-I teach Middle School.
It's not you-It's WU.

Offline WA7FWF

  • Contributor
  • ***
  • Posts: 138
  • Blitzortung 1196
Re: Seismographs and thunder
« Reply #4 on: March 07, 2021, 11:55:42 AM »
I have a raspberry shake  earthquake setup outside in the ground about 3 feet from the foundation of the house sitting on and surrounded by several hundred pounds of concrete.  It easily detects trains 2 miles away, cars and motorcycles 150 feet away and during  quiet times it has even picked up me sitting in my chair shaking my leg inside the house.
  And yes it has picked up the rumble from nearby thunder.

Kevin

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1771
    • Weather at Eau Claire, WI
Re: Seismographs and thunder
« Reply #5 on: March 07, 2021, 11:59:22 AM »
Chief-David:
Well, add football games to the record, I guess.  As they say in Central Wisconsin, Who woulda thunk it?

Where was the graph taken from?  I see it was an NFL game.

Having been in Camp Randall stadium during a full house home game of the Badgers Football, when the student section begins to get limbered up a bit and dancing in their end of the stadium to the song "Jump" which they are all excited to do, I can recall feeling the other end and sides of the stadium shake.  (The Engineering Dept has done extensive analysis (someone's Masters?)  to show that the structure is in no danger.... yet.)

Anyway, I'm not talking ordinary thunder, although that can be quite forceful.  I'm thinking of the maybe once a year or every couple years storm (that I am present to experience) in which a long rolling thunder causes the house to shake.  It must have traveled many miles to get to my house since often the storm seems to have passes and is subsiding, with the quiver of the house going on for a few seconds to as long as 5 or 6 seconds. 

I know Edward Teller watching his University's seismograph to see that the Teller-Ulam idea  worked to fire the first real fusion device.  But then that was a big thump in its own right.

I will check to see if there are sources at Morris to see if they have an idle student or teaching assistant who might be able to discuss it further.

Thanks.  Dale
ECWx.info
&
ECWx.info/t/index.php

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1771
    • Weather at Eau Claire, WI
Re: Seismographs and thunder
« Reply #6 on: March 07, 2021, 12:04:35 PM »
Kevin and Chief-David:

You guys bring to mind the old phrase:  "So many things to do, and so little time."  I'm off to look at that, too, I guess just so I know what is out there.  A few years ago there was an article in the SciAmerican Amateur Scientist section when it was resurrected for a bit saying that the new accelerator chips were so sensitive that a relatively easy to assemble at-home device could be made.  I have the article here somewhere, but never got around to doing more than reading it.  Now I understand that many cellular phones/smart phone have acceleromeeter chips in them, too.  Maybe there is an 'app' for zip tying your cell phone to a metal pole set deep in bedrock and sit back to watch the display? 
ECWx.info
&
ECWx.info/t/index.php

Offline zoomx

  • Contributor
  • ***
  • Posts: 122
Re: Seismographs and thunder
« Reply #7 on: March 11, 2021, 12:19:29 PM »
Most homemade seismometer measures ground movements (ground velocity), small ground movements and usually they are more sensible to its own resonance frequency. You can have such small movements form many other sources other than an earthquake so usually seismometers are far from these noise sources.
Professional seismometer now are different, they have a mass but this mass is steady and the electronic measure the energy to put this mass steady. This way they detect waves in a large band.

new accelerator chips were so sensitive that a relatively easy to assemble at-home device could be made.  I have the article here somewhere, but never got around to doing more than reading it.  Now I understand that many cellular phones/smart phone have acceleromeeter chips in them, too.  Maybe there is an 'app' for zip tying your cell phone to a metal pole set deep in bedrock and sit back to watch the display? 
You are talking about MEMS accelerometers. Unfortunately most of them are not so sensible, sensible ones are very expensive and are not so small. Anyway there are apps to record the signal of smartphone accelerometers.