Can somebody please....(what IS that!?)

I am just as curious as all get out! What in heaven's name is rumbling so deeply and moving my home, here off of Baxter Rd. and the 15 freeway in Wildomar? I've looked in to the rumbling before because there have been episodes of consistent blast sounds, with some sounding so large, so close, that the windows of my house shook loosely in their frames! The general consensus has always been our fairly-near proximity to Camp Pendleton, which then filled me with pride and reassurance knowing that our fine men and women of the Marine Corps are doing a very good job at staying honed and fined tuned, ready to get down if given the need. Phew! ;)

Now today though, today was different. It's Tuesday, November 1, 2016, a bright and lovely day here in the Elsinore/Temecula corridor, and sometime in the earlier part of today I suddenly heard a low rumble. It was the kind of rumble that is usually generated by a heavy commercial truck of some sort, traversing over a portion of nearby roadway, or freeway overpass(?) that does indeed give off a handsome roar in its own right, but it always ends abruptly, and you can immediately ascertain that the rumble came from a smaller source, that came and went; obviously just passing by or over. This rumble today, it started at a sizeable distance. Instantaneously though, just as I acknowledged the presence of the sound, it traveled, rampantly, low in the ground, and raced its way right on over to underneath my sitting spot. Just as the subterranean vibration came under me, my home then made a shimmy.

Our home is a small, humble affair, sitting on a raised foundation that I am sure would benefit from some fresh attention and tending to, so it may have more suppleness than some other nearby structure, that may not have batted an eye. But, mine twisted ever so gently, and made creaks all about where I sat; a very sure fire indication that this growl from below was truly the cause for the shudder. That then, I was a little more concerned than usual. I seriously doubt that, THAT was from Pendleton! If so, what the heck are they practicing o'er there!? Are they mining a 10 lane super highway 1200 feet below the elevation? That sure is how that felt! And sounded!

What brings me out this evening, to ruffle those feathers of yours, my fellow friends and neighbors, I have now experienced three of these tremendous guttural rumblings. They seem far too great to be of practice, training materials, don't you think? Has any one of you also, felt these movements and heard these sounds today? It is highly probable that my naivety exudes me, and in that there be far too many factors that I just simply am unaware, I do declare. Yet, still, I feel certainly otherwise.

So, friends and neighbors, if you would grant me any of your wizened or educated knowings? I would be most grateful!