Origins of the Big White Marble
From the moment I saw it shining down there on the sea bottom I was hooked. The improbable sight of a gigantic, brightly white, roundish almost spherical rock, defies explanation, but certainly begs for it. In fact, this post is devoted to my current obsession with this freakish geologic anomaly.
I call this thing an anomaly, but is it really? After all, I’ve only been diving for just over a year and with only about 60 dives in a handful of locations, all of them in the Philippines, perhaps others have seen similar giant globular stones. Until I hear otherwise though, I will continue to assume that MY giant white sphere is unique.
First its dimensions: From the video, based on Don’s presence on and near it, the round rock appears to be almost 6 feet in diameter across the top. From top to bottom it’s obviously much less than that, probably barely 4 feet. I’m gratified that I have clips of my dive partner in proximity to it; otherwise, if I based its size strictly on my faulty memory of it I’m sure I would try to say it’s much larger and more perfectly circular than it actually is.
On that note, I now know that my memory of it is based mostly on examining it from above. I remember that I mostly stood on it or hovered directly over it, which is why my impression of the shape has been that it was like a giant chalky marble. But, now that I’ve watched the videos several times I can see that its true shape is squatter, more like a pill or an enormous M&M.
As I said though, in my mind's memory the stone was much larger and therefore I also imagined it to weigh some enormous amount, perhaps in the tons. I’m sure it probably is quite heavy but I’m reconsidering the idea that it weighs some enormous amount.
Aside from the reality that it’s not nearly as big as I thought, there’s also the possibility that its volcanic origin might also mean that it’s not nearly as heavy as it might first appear. I say this based on my own local experience with the volcanic stones I find all the time while digging in my yard.
We live on one of Pinatubo’s pyroclastic plateaus, so I can say fairly confidently that every rock and stone I find out there is volcanic in origin. Most of the stones I’ve found, just like my underwater find, are roundish and smooth. I don’t know if this is because they were river stones at some time in their existence or if they were formed that way. I will guess that its most likely the latter. There is so much I DON’T know, but the point is that aside from their smaller size there is a distinct similarity to their big white round underwater Claveria cousin.
So what about its weight? The big white marble is obviously volcanic in origin, as is all the rock in the lagoon area. Since it IS volcanic and LOOKS porous, there is a distinct possibility that it might be a large pumice boulder. It looks very much like the pumice I dig up in my yard all the time. Many of the pumice stones I find are actually buoyant. I tell my girls they are "magic stones" and then have them place the stones in the fishtank where they float for hours before becoming waterlogged.
But, not all volcanic rock is light; from what I've read, many types are quite dense and heavy. Still, I MUST suppose that the big white stone is actually relatively light in weight, based on my observation of the stone’s surface. Look closely at the exterior and it’s obvious that whatever process is forming (and maintaining) its polished circularity is even now in progress. From top to bottom flecks of its exterior are being chipped and ground off. I believe there is only one answer as to how such a thing could be happening.
And I do not misspeak when I say it IS happening. From the look of it the flecking and grinding process is most definitely ongoing. It is also obvious that since the stone is round and that the fresh reductions on it are all over its surface, including and especially the upper areas, that the process causing this controlled external "polishing" is the movement of the stone against the rocks and boulders surrounding it. That means that the giant ball of rock is not just rolling, but tumbling! Trying to imagine such a thing is almost impossible, but it’s THE only explanation.
THAT is the reason I postulate that its density must not be as substantial as its bulk makes it appear. Clearly a very heavy rock would not be able to roll around as this one apparently does; not unless it was perfectly round and perching on a flat surface. And look again at the big white stone; it is actually nesting among other stones, thus it would take an enormous amount of force to get it rolling around in that “nest.”
So what is the enormous “force” that could roll around this giant boulder like a marble in a can? And there IS visual evidence that the “marble in a can” analogy is exactly right—look at the white hit marks on some of the massive stones surrounding it. Some of the white scuffs appear to be more than twice the height of the stone itself.
Considering the violence of such a thing, it’s surprising to me that the ball shaped boulder has not cracked and broken into pieces as its being flung around. As to what could possibly be doing the “flinging,” I’m certain that it is a combination of two forces, or better said, it’s a combination of one force powerfully channeled by a confluence of both geologic and hydraulic conditions.
The geological conditions are two, or even threefold:
First the "big marble" itself—I’m fairly certain that it first originated when it broke off one of the slabs of rock partially forming its “nest,” probably when the "mother slab" itself slammed into the ground. See the “mother rock” in the photo? It’s “baby,” the eventual marble shaped rock, must have already been roundish
at “birth,” or nature’s “shaping process” could never have begun to begin with. If it wasn’t already fairly round at its inception then the forces of nature would not have been able to start racking off the non round bits. And as I discuss above, the material it’s made of must also be relatively light, yet also durable, or it could never have lent itself to the process that continues to erode the rock ball into an ever smaller and smaller version of itself.
Continuing to guess geologically, because I really don't know what I'm talking about here, the second existent condition is the actual “engine” of “the marble shaping process.” This engine is the long chimney-like channel that faces directly into one side of “the marble's nest.” It's actually a deep narrow fissure that reaches all the way up the side of the sea wall. From where it erupts at the surface all the way down to the sea floor may well measure more than 30 feet. And it’s not just the height that gives it so much power; it also has length, where it spans narrowly at least 25 feet from the far wall all the way to the point where it empties into “the nest.” This narrowness at the "exit," smaller than a man, acts like the restriction on a fire hose that allows it to spray water at enormous pressures.
Watch the video for an example of how this engine works and of its power. You can see how both of us are being mightily pulled and pushed while in the inner confines of the chimney’s horizontal length. And keep in mind that the wave action driving that powerful surge at that moment is minimal as can also be seen in the video when I surface up at the top of “the chimney.”
Keep in mind that strong storms continually rack the northern coast of the Philippines, and even stronger typhoons strike two and more times a year. These storms, big and small, drive water with super intensity down and out that channel directly into and under our large white marble; and when it does, the release of that tremendous hydraulic power rolls it around and up the sides of its expansive rock nest, all the while chipping and flaking off pieces as it smashes and mashes into the surrounding stone.
I looked everywhere in the vicinity of the marble trying to find any of its chipped off pieces, but could find nothing, probably because the flecks come off so small that they are unrecognizable as having once been part of the stone, or perhaps the power of the rushing water sweeps it all away.
Trying to put it into some kind of perspective, how many years, or decades, or even millenia has it taken to form that intriguing white globe of rock? Perhaps I'm being more sensational than erudite, but I'm thinking that the whole area was above sea level 10,000 years ago at the end of the last ice age. If so, the base of the escarpment back then, where the big marble nests today would have been high and dry. So my bet is that the marble has been in the making for at least 10,000 years which is when the sea level got high enough again to reclaim it. Having said that, I would LOVE to be corrected by an honest to God geologist.
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Okay, hold the phone! I wrote all the above last night during what I THOUGHT was an ingenious flash of brilliance. I think now that at least SOME of my suppositions might turn out to be more of a flash in the pan than brilliant. I know, NO surprise there.
At the fitness center this afternoon a fleeting moment of clarity hit me while pondering the giant underwater marble. I reminded myself to check the stones in my rock garden. Sure enough, when I got back here I walked right up to one round one out there that looks susupiciously similar to The Big White Marble. Check out the photos below.
I'm not rethinking ALL my theories, but I AM beginning to believe that The Marble perhaps did NOT begin its individual existence as the broken off end of a fallen "mother rock." I changed my mind a few hours ago after examining the stone in my rock garden.
We found the pock marked ball shaped rock in the Abacan River bed. It may have become rounded during its life as a river stone, but I'm thinking that it has looked the way it does now since it spewed out of Pinatubo's caldera thousands of years ago. When I found it today and carefully examined it I was struck at how similar it is to its big underwater brother.
I believe now that both the small one AND the big one both attained their present appearance exactly the same way, volcanically; if so, then all that underwater tumbling and grinding away action has little to do with how it got to be round. I'm really thinking now that it started out that way.
I do believe that its uniquely brilliant whiteness stems completely from the polishing action of constantly being thrown around the inside its walls of hard stone. The thrashing bashing crashing rock ball is like a pestle and mortar, constantly smoothing its surface and keeping the normal sea growths from discoloring it.
None of that takes away from its singular magnificence. It gleams, brilliantly white, eerily irridescent, sitting majestically alone, penned in by visually lesser rocks colored contrastingly pink and gray.
It really amounts to a miracle. I mean how unlikely is it that all these conditions AND this huge round rock could come together in this one place? I think its just about impossible; yet, there it is.
I've run the videos of it many times now and I still find this thing stunning, especially when considering how high the hit marks are on many of the encircling stone faces. Even if this thing is some form of porous volcanic rock, like pumice, I know it must be fairly heavy. I would LOVE to be able to be there when the hydraulics become powerful enough to spin and toss it high around in its enclosure. Can you imagine that! Of course, being there physically would be a death sentence, so you can't have everything. Then again, maybe The National Geographic could put in place a robust underwater camera to record the incrdible event? Anybody know somebody?