I thought it was haarp doing its thing or something.. it was really weird! never heard any thing like it.

HAARP DOES NOT DO THIS KIND OF STUFF, YOU FOLKS KEEP BUYING INTO THIS CRAP. IT CAN ONLY HEAT THE IONOSPHERE, IT DOES NOT RUMBLE OR CAUSE QUAKES. IT IS FOR WEATHER MODIFICATION.
The rumbling and other strange sounds which have no explanation are related to crustal movements. And its not going to decrease. These are going on in many areas of the world right now. south England has had it for weeks now, I have contacts there. They are erasing the earthquake drums a lot to cover up what is coming.