Good morning. I live in one of NYC boroughs so my raspberry shake picks up different types of ground motion. Some I know defiantly like the trains going by to enthusiastic crowd participation at concerts of music festivals near by. However I know there are other “things” happening and I would like to decipher the source. I’m pretty certain they are not from seismic activity. The recent 7.5 earthquake from Japan did not obviously show compared to another station further north from me.
Is there a source or tutorial that can help me decipher and maybe categorize the type of waveforms created by my seismograph.
Al beat me to it… It shouldn’t be too long before there is some level of documentation.
The problem is, there are so many things in the modern world that shake the eart, both locally, and at distance, as well as seismic events, that identifying all is close to impossible. But with time, and experience, you will get pretty good at sorting out what is what and identifying the seismic events.
The spectrogram normally gives you a quick indication if the signal is seismic or not. If not seismic, the spectro might show a signature that provides a general category of what is causing the signature… helicopter, washer, dryer, furnace… etc.
As Philip pointed out, there are so many possibly non-seismic things that can be picked up. You have to play detective at times to figure out the cause. I have run outside many times to try and hear if something locally was causing what I was seeing on the RShake. There are still some signatures to this day I have no idea what the source is. All I know is that they are not seismic.
