I believe there are places on Earth where people have traditionally said that you can sometimes hear a mysterious hum. I imagine that most of the hum being discussed here is at frequencies which humans cannot hear — but it would appear that the modulation sometimes rises up into our range.
Maybe this noise is what animals hear and then move out of dangers way when earthquakes are imminent.......
must be a wavelength phase thing,, the right spot at the right time.. there are some spots that are reputed to be focal points for energy flux fields on Earth.
I wonder if its related to tooth fillings or jewelry.. Gold and amalgram, heightened solar activity, hmmm..
I’ll have to dig a little deeper on this one.. :-)