Why is the Earth Missing a Billion Years of Rocks? (bbc.com) 122
"A mystery lies deep within the Grand Canyon: one billion years' worth of rocks have disappeared," Space.com reported last week.
The BBC explains: Today geologists know that the youngest of the hard, crystalline rocks are 1.7 billion years old, whereas the oldest in the sandstone layer were formed 550 million years ago. This means there's more than a billion-year-gap in the geological record. To this day, no one knows what happened to the rocks in between.
While the missing rock is particularly obvious in the Grand Canyon, the phenomenon is ubiquitous. "It's one of these features that pretty much occurs under a lot of people's feet, when they don't even realise it," says Stephen Marshak, professor emeritus in the Department of Geology at the University of Illinois. He explains that in the centre of any continent, whether you're in the United States, Siberia or Europe, if you drill down far enough you'll hit the two layers of rock involved in this mysterious geological anomaly....
[F]inding out what happened during, and led to, the missing billion years is no trivial matter. There are two reasons for this. The first is that it just so happens to have occurred immediately before another inexplicable event — the sudden proliferation in the diversity of life on Earth 541 million years ago. The Cambrian explosion refers to an era when the oceans suddenly shifted from hosting a scattering of weird and unfamiliar creatures — such as triffid-like leaf-shaped animals and giant steamrollered ovals which continue to defy all efforts to categorise them — to an abundance of life, with many of the major taxonomic groups around today. It happened in the space of just 13-25 million years — an evolutionary twinkling of an eye...
The second is that it's thought Earth underwent radical climate change during the lost years — possibly turning into a giant ball of ice, with an almost entirely frozen surface. Very little is currently known about how this "snowball Earth" formed, or how life managed to cling on.
They share the three good theories. First, "snowball" — the earth develops a global ice sheet, with the speedy glaciers wearing away surface rocks.
The second theory is that it was all lost during the erosion of the supercontinent Rodinia.
And theory #3 is: confusion. The BBC cites new research that "suggests that the epic interruption in the geological record was not a single, discrete phenomenon — but instead is actually at least two mini-gaps, which look like one big one because they occurred at around the same time." Even the missing rocks on the two sides of America's Grand Canyon "may instead have vanished in several separate events over the course of several hundred million years."
The BBC explains: Today geologists know that the youngest of the hard, crystalline rocks are 1.7 billion years old, whereas the oldest in the sandstone layer were formed 550 million years ago. This means there's more than a billion-year-gap in the geological record. To this day, no one knows what happened to the rocks in between.
While the missing rock is particularly obvious in the Grand Canyon, the phenomenon is ubiquitous. "It's one of these features that pretty much occurs under a lot of people's feet, when they don't even realise it," says Stephen Marshak, professor emeritus in the Department of Geology at the University of Illinois. He explains that in the centre of any continent, whether you're in the United States, Siberia or Europe, if you drill down far enough you'll hit the two layers of rock involved in this mysterious geological anomaly....
[F]inding out what happened during, and led to, the missing billion years is no trivial matter. There are two reasons for this. The first is that it just so happens to have occurred immediately before another inexplicable event — the sudden proliferation in the diversity of life on Earth 541 million years ago. The Cambrian explosion refers to an era when the oceans suddenly shifted from hosting a scattering of weird and unfamiliar creatures — such as triffid-like leaf-shaped animals and giant steamrollered ovals which continue to defy all efforts to categorise them — to an abundance of life, with many of the major taxonomic groups around today. It happened in the space of just 13-25 million years — an evolutionary twinkling of an eye...
The second is that it's thought Earth underwent radical climate change during the lost years — possibly turning into a giant ball of ice, with an almost entirely frozen surface. Very little is currently known about how this "snowball Earth" formed, or how life managed to cling on.
They share the three good theories. First, "snowball" — the earth develops a global ice sheet, with the speedy glaciers wearing away surface rocks.
The second theory is that it was all lost during the erosion of the supercontinent Rodinia.
And theory #3 is: confusion. The BBC cites new research that "suggests that the epic interruption in the geological record was not a single, discrete phenomenon — but instead is actually at least two mini-gaps, which look like one big one because they occurred at around the same time." Even the missing rocks on the two sides of America's Grand Canyon "may instead have vanished in several separate events over the course of several hundred million years."
God fucked up 6,000 years ago (Score:4, Funny)
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Next time that lazy hack should take a few more days and get it right. It's not like he had a manager breathing down his neck who had a deadline to meet.
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Emmm.. for feck's sake - have you even read the stories?
* God created Mary without Original Sin. The only human since Eve. (Do you really think that was God's choice?)
* Jesus turned water into wine for a friend's party just to get her off his back.
* She was assumed into heaven. Even Jesus had to ascend on his own.
* Her son was a literal god.
O_O
Sure if that's not the portrait of the stereotypical Jewish Mother, I don't know what is!
(I know this could be read as offensive in roughly 50 different ways. I mean
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She was the proverbial Jewish mom. She thought her son is god and her son though she's a virgin.
Plus, she probably kept nagging how every woman isn't good enough for him that he was still a bachelor at 33.
Re: God fucked up 6,000 years ago (Score:3)
Could've been a localized ice age which the built up setiment washed away once the ice thawed taking the material with it.
Yes, I am really grasping at straws here.
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Re: God fucked up 6,000 years ago (Score:2)
And it could really have been eaten up by razor toothed leprechauns.
Seriously, the point is to find a plausable explaination of why those rocks disappeared and not delve into outragious explainations, at least not until we are absolutely sure we have no idea why those rocks are not there.
Also, we really don't give our ancestors much credit. The pyramids were built by humans, and the Egyptian empire was very advanced in the technical sense. All of the cool stuff just didn't start happening in the late 19th a
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Ever wonder why The Holy Bible jumps directly from Garden of Eden to Earth Full of People? It's the same thing.
Re:God fucked up 6,000 years ago (Score:4, Informative)
No, it was clearly Slartibartfast and his colleagues having an extended Friday lunchbreak down the local pub. When they got back on the job they dialled in the wrong age settings on the rock materialization beams.
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"Pffft, I'll just delete my boo boo. Stupid humans will never notice, and even if they do, they'll never figure out why."
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one billion years' worth of rocks have disappeared,
Nobody leaves zer room!
Re: Ah, yes, anti-religious bigotry ... (Score:5, Insightful)
Biblical literalism, especially as it pertains to the opening verses of Genesis, is either expressly at variance with doctrine (i.e., heresy) or considered merely a ceremonial tradition in most major denominations of the major Abrahamic faiths.
Popes, Rabbis, and Imams better than you have devoted their work to debunking fools who can't comprehend the possibility that the word of their God sometimes comes in metaphor, to say nothing of the tireless philologists and theologians who pieced together the actual textual history of the scripture and identified when and why each piece was added.
Children who cling to dumbed-down, four-times-translated fairytale versions of their holy texts and never lift a finger to learn about their faith and what it means aren't good Christians (or Muslims, or Jews, or Mormons, or Baha'iists, et cetera), and never can be.
Now go learn Hebrew so you can become a civilized Greek.
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"four-times-translated": What is this nonsense supposed to mean? The Old Testament (the Hebrew Bible) was written in Hebrew (mostly) and a little Aramaic. The New Testament was written in Greek. So there's one translation step between those and English (or most any other major language), because the translations are done by scholars who know those languages. Even the translators of the King James translation, published in 1611, knew those languages (although there have been later discoveries about Koine
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See this astonishing mess [wikipedia.org] and then consider that the KJV uses the Septuagint and the Vulgate to decide readings for various OT passages. There are also, of course, major events in editing and composition to consider, like these [wikipedia.org], and these [wikipedia.org], and some rather striking episodes in how commentary and scholarship has contributed to the interpretation of the material (at least among people who are interested in understanding it rather than just waving it around as an excuse to cherry-pick whatever they feel like)
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I still don't get it. None of the links you cite has to do with multiple episodes of translation; one of them, for instance, points out that the Catholic Church chose as its authoritative translation the Latin Vulgate, which was translated from Hebrew and Greek, while the Protestants (Martin Luther in particular) chose their own translations from Hebrew and Greek. In each case there was a single translation step, from Hebrew and Greek to the target language. And no, "four-times-translated" has nothing to
Or ... (Score:1, Troll)
... it could be that we don't know what the flip we're talking about.
Our confidence level in non-experimental science is bizarre.
Re:Or ... (Score:4, Informative)
The article is quite clear none of this is established science and there are plans for future research to close the gap. So it is more likely you don't know what you are talking about.
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Most scientists believe their sliver of "Shit you Think You Know" is much bigger than it actually is.
Still not as big as the Kardashians' sliver though.
*puts up hands* Now hear me out (Score:4, Funny)
"Aliens"
Re: *puts up hands* Now hear me out (Score:2)
They really wanted to say Terraforming, but its more believable than most of the garbage archaeologists hypothesise so they went with the tooth fairy did it instead.
Re: *puts up hands* Now hear me out (Score:5, Interesting)
Errr, most science works by making hypotheses and then doing the research to confirm or deny. But maybe you could tell the archeologists they are doing science all wrong, I'm sure they'll listen to you.
Re: *puts up hands* Now hear me out (Score:5, Informative)
Errr, most science works by making hypotheses and then doing the research to confirm or deny. But maybe you could tell the archeologists they are doing science all wrong, I'm sure they'll listen to you.
This. When working with hypotheses, Scientists throw out ll kind of ideas. They even throw out wild-ass guesses, or WAGS. Then you discuss and try to tear all of them apart. You pick the remaining possibilities, and take them from there.
And it's a pity, because the winnowing process is fun. And if new data comes, it starts all over again.
Science journalists like headlines like "Scientists stunned by" (fill in whatever they are stunned by) while in fact, they are excited.
And seemingly, most people don't like it when they change the script. We've seen recent examples of that in some fields.
The missing "rock" is a fascinating issue. One of the most fascinating parts is that we're still trying to figure it out.
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"Science journalists" are a very rare breed - the overwhelming majority of journalists are "English" (subject, not language) or history graduates who haven't touched a science course since before the started growing pubes.
(There are exceptions - they are rare.)
BTW, this story isn't exactly news - I was having exactly this discussion (with different data, some overlapping)
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"Science journalists" are a very rare breed - the overwhelming majority of journalists are "English" (subject, not language) or history graduates who haven't touched a science course since before the started growing pubes.
(There are exceptions - they are rare.)
BTW, this story isn't exactly news - I was having exactly this discussion (with different data, some overlapping) in 1980. Or 1981 - I'd have to check a diary.
No doubt about the age of the story. It's not my field, but I've always been interested in Geology. But I remember it from long ago too. Editors - We had a technical editor who fit into the "English" class mode. She wasn't terribly knowledgable, but was a really great lady and competent outside of science.
What she did though was teach me a few ways to zip up my writing which I adapted and it ended up working out well. Just made things a lot more terse, less of the problem some have of trying to be too i
Re: *puts up hands* Now hear me out (Score:5, Insightful)
> most science works by making hypotheses and then doing the research to confirm or deny
And also picking a favorite hypothesis among all the potentially valid ones, then dividing into tribal camps with bitter rivalries among them, featuring derision, jockeying for tenure, data falsification, p-hacking, and sabotaging grant applications of rivals.
"Professional Science"
Re: *puts up hands* Now hear me out (Score:5, Insightful)
That is how "most science" fails, not how "most science works". Yes, this stuff happens, but it is a stain on the community, not on science itself.
Re: *puts up hands* Now hear me out (Score:2)
Re: *puts up hands* Now hear me out (Score:1)
->But maybe you could tell the archeologists they are doing science all wrong, I'm sure they'll listen to you.
How about we start by all of us just not calling politicised unrepeatable random guesses "science"
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But maybe you could tell the archeologists they are doing science all wrong, I'm sure they'll listen to you.
And then they'll say "The geology department is down the hall".
Re:*puts up hands* Now hear me out (Score:4, Funny)
Re: *puts up hands* Now hear me out (Score:4, Funny)
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"Aliens"
Bigfoot.
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Aliens Versus Bigfoot
Marvel lore legend (Score:2)
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You're hired!
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Get a haircut!
Rock vs fossils (Score:5, Insightful)
On one hand the article says there are no rocks from a billion years.
On the other hand, it says that we know about animals back then.
But if there are no rocks, then what are those fossils from which we know about the animals?
Re:Rock vs fossils (Score:5, Informative)
All the layers are there. It is just that, for the layers of that time period, they were rotated / tilted so they are not horizontal, then they were ground off from above and below. So a huge amount is missing, but all layers are represented. I mention it in more detail in a comment further down. This diagram shows the area in question. It's layer B.
https://play.google.com/books/... [google.com]
Re:Rock vs fossils (Score:4, Informative)
Its incorrect to say there are no rocks from that period. But they are rarer, and the unconformity is widespread. There are still pockets here and there of rocks from the period for whatever reason escaped whatever it was, probably glaciers . Some of them
Re:Rock vs fossils (Score:4, Informative)
To elaborate further some of the surviving rock from the period may have been offshore where the ice wouldn't have made contact with the rock, or they could have been in deep basins such as rift valleys , or rocks caught in subduction zones, or caught within thrust faults, where some rock had been pushed deeper into the crust in the subduction zone. I know some of the rocks from the period are in the UK and Nova Scotia which were coastal areas at the time like today, but were positioned of the coast of Africa.
Re:Rock vs fossils (Score:5, Informative)
On one hand the article says there are no rocks from a billion years.
Poorly written.
There are rocks from that period, including with fossils.
Some event certainly did happen and resulted in a really bizarre state of those rocks in the geological layer, so the article isn't completely talking out of its ass. Yet this particular statement about "no rocks" is incorrect.
https://en.wikipedia.org/wiki/... [wikipedia.org]
If you look at their "Figure 1" image, layer 2 at the bottom is the one in question.
It's turned partially sideways, for reasons unknown.
Normally we can infer fossils above other ones are more recent, and the fossils below are older.
With this strange angle this doesn't always work all that well since fossils that used to be deeper can actually be closer to the surface in some places on earth, and much much deeper in other places on earth.
However there are fossils present, and they are at a frequency similar to below, which is far less frequent than the layers above.
That's how we know there was life during that time, and we know from the many more fossils above that there was a few orders of magnitude more life after this period than the one before it.
It's just very difficult to pinpoint exactly when within this angled layer the explosion of life happened.
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Good, good.... (Score:2)
It's God fucking around again (Score:1)
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he loves to fake and leave confusing evidence that world isn't 6,000 years old.
Well, a missing "billion" years would seem to pose a slight problem to your theories.
But no, I guess it's you who should be smug, because what's a billion years between friends?
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I'll guess you are a Christian nutjob. We normal people have science which is happy to accept new research as it becomes available. You, on the other hand, are relegated to reading obscure meanings into ancient texts, none of which are the originals; the only "copies" of the Jewish Bible were made several hundred years after Jesus popped his cogs. Even the story of Noah and the Flood were "gifted" from the Epic of Gilgamesh, which was an ancient Sumerian myth.
And if you want to get all New Testament about i
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We normal people have science which is happy to accept new research as it becomes available.
Oh, you sweet summer child...
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You are clueless. There are many things you have wrong, but let me pick on just one: "the only "copies" of the Jewish Bible were made several hundred years after Jesus popped his cogs". Guess you never heard of the Dead Sea Scrolls?
Pardon me, let me mention another one: Yes, Greek was at one time written without word breaks or punctuation--as Chinese and several other languages still are today. So what? I do not know of a single place in the Greek New Testament (or for that matter in other Greek writing
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So who created your creator? Your creator didn't need one? Then why not just cut out the middle man and accept that the universe has no more need for a creator than the one you claim, without proof, has always been around?
You might as well love Chuck Norris. He has rules, too...probably not much different from the ones you try to pass off as a moral code.
Apocryphal Student Geology Story (Score:5, Interesting)
Sometime after Mount St. Helens blew its top, a geology professor took his students on a field trip to the area. He pointed to a layer of black sandwiched between lighter colour strata of a tractor machine cut on the side of a small hill.
He asked his students "How many years old was the later of black strata?"
The answers came back in varying degrees of millions of years.
Then he told them that the layer of black strata was the former National Forest Station parking lot.
Re:Apocryphal Student Geology Story (Score:5, Informative)
These sorts of stories are common on YEC sites. If this were a true story these would be very poor Geology students or maybe a geo 101 class as the first you need to establish is what process was laying down the layers. Every geologist (or student geologist) know layers can be deposited quickly as flooding is a very common geological process. The questions that should come up are pollen gradients present which would indicate the layers represent years? are fossils or evidence of bioturbation in the layers? radiometric data? etc.
Transcript. (Score:1)
Long, long ago, in an orbit not so very far from here...
"KERZAppklonkklonkthunk."
"Ah, er. Lord Vader. The turbo laser focussing matrix appears to have tripped the hyperplasma fuse array."
"I HEARD THE WEAPON FIRE?"
"Er, approximately 5% yield. The surface of the planet has been erased to a depth of a few hundred meters and the species that posted the 'gasping grabber dance-off meme' are extinct, but the star system still only has one asteroid feature."
"A PITY, BUT WE CANNOT AFFORD THE DELAY THIS EQUIPMENT FAI
Possibly? (Score:5, Interesting)
"... possibly turning into a giant ball of ice, with an almost entirely frozen surface. Very little is currently known about how this "snowball Earth" formed, or how life managed to cling on."
It's got some strong evidence. The drop-stones alone are a humdinger!
As for how, it's not hard to imagine the bulk of atmospheric carbon, pre-snowball, ending up at the bottom of the oceans. There wasn't any plants on land, so no chance of circulating through fires. And with very little animal life to produce CO2, that left volcanoes as the only source of CO2. Algae had free rein to clean the atmosphere spotless.
And once the snowball formed, the algae mostly dies off and the volcanoes slowly recover the CO2 levels until the ice suddenly melts in a strong positive feedback. The high atmospheric CO2 level now creates intense acid rain until the CO2 level can be brought back down.
Result is prolonged dissolution of rock.
How they knew 10,000 feet was missing (Score:5, Informative)
This article reminds me of National Geographic articles I used to read growing up. While they are wonderful prose and throw in lots of human elements and a bit of suspense and intrigue, it sure makes it hard to pull the meat out of the article. Seems more for the layperson to sit back and read casually instead of something to actually learn from and extract information out of.
It wasn't clear at all how an explorer 150 years ago knew that 10,000 feet of rock was missing. It's just glossed over, and since this was before radio carbon dating I was wondering how that could be the case. The original document has a diagram that reveals how they came to that conclusion:
https://play.google.com/books/... [google.com]
If you look at layer B, that strata is rotated at an angle compared to to A and C above and below it. Since it's at an angle, you can also count its thickness as you go from left to right, summing up the thickness of all the layers you see. That is where the 10,000 feet total comes from. It's as if the horizontal layers were all tilted, and then ground off from above and below, leaving a cross section of the original layers.
Re: How they knew 10,000 feet was missing (Score:4, Insightful)
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I noticed this in "science" shows the past 10 years, maybe more, including National Geographic. They have built in human interest stories, getting feelings and other struggles beyond just a historical description of the unfolding of a discovery or invention.
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All science articles seem like that now. There was one linked from here the other day about quantum something. A few paragraphs in it started talking about the braided hair of the scientist tumbling gently down his shoulder. I don't believe for a second that readers of this kind of article are interested, so my assumption is that it's a journalistic trend, hopefully one that will end.
Pop Culture. Possibly trying to get otherwise disinterested young ladies to think that science is cool.
Of course science is cool. But only to people who know it's cool from the start, not torn between becoming a Nobel winning scientist or the next Beyonce.
note: this is a real example - in our take our sons and daughters to work day, the number of young ladies that wanted to be a Pop Star Diva far eclipsed the number who wanted to have STEM careers.
Yet the Scientists and engineers I worked with who are
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All science articles seem like that now. There was one linked from here the other day about quantum something. A few paragraphs in it started talking about the braided hair of the scientist tumbling gently down his shoulder. I don't believe for a second that readers of this kind of article are interested...
But what if it's an article about the physics of gently tumbling braided hair?
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I had a caving associate who got an Ignobel prize for almost exactly that. (2012, Physics [improbable.com])OK, pony tails, not braided hair, but the last I heard, they were looking to extend the work.
Incidentally, since the standard howl here is that "scientists only do it to secure more funding", my associate did this work while employed by that famous charity "Unilever", as part of quantifying the physics of hair, so they could make claims abou
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That is good to know and I don't like how so many journalist articles are basically watered and dumbed down. Most people really are smarter than that. Its interesting how they could estimate the amount of missing rocks and thanks for bringing that up
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What's funny is that it's still watered down, and no one seems to be able to tell the difference.
Not so much of a mystery (Score:5, Interesting)
The feature is called the great uncomformity. Its really not all that much of a mystery because as is said, completely rational, almost hard to belief if it was not the case, explanations exist for it, such as the combination of Rhodinia and a vast ice sheet which covered the whole thing and scraped the continents clean of sedimentary rock. If its an ice sheet, then the cambrian explosion makes sense, because the ice sheet goes away, sedimentary rock starts piling up again, and life takes off in the warmer climate.
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... amongst other things, because sediments from that time interval are known, they're just relatively uncommon. In the BBC's "back yard", there has long been a well-known "gap" like that, from an estimated 1700 Myr ago to the base of the Cambrian (540Myr) - in NW Scotland, from the later Lewisian to the "Basal Quartzite"). But since the improvement of radiometric dating since the 1960s it has also been shown that an intervening series of terrestrial sediments (the T
Obvious (Score:5, Insightful)
" within the Grand Canyon: one billion years' worth of rocks have disappeared,"
Those damned tourists, they steal everything that's not nailed down.
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Re:Obvious (Score:5, Funny)
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If you can't find a way to dismiss the evidence, then change it.
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Sloppy time travel (Score:1)
looks like an obvious cut+paste error
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looks like an obvious cut+paste error
It's a missed graphics rendering issue. It'll get fixed in the next patch.
Erosion? (Score:2)
I'm a total layman of course, like everyone here, but I always wondered:
This sounds like a water world or glacial world, and that part of the ground just got eroded away. Meaning it is still there, but put through an extreme blender.
You may be able to test that hypothesis with some kind of isotope dating that would mismatch some other kind of dating that can't survive erosion.
I wonder what crazy stuff we missed from that billion of years.
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It's not even a particularly extreme blender. I can take you to places where 1700 Myr old granulites (very high grade, high pressure, high temperature metamorphic rocks) are overlain by 1000 Myr old river channel sands and lacustrine mudstones (hint : dessication cracks), themselves carved into valleys with kilometre-tall walls and overlain by Cambrian (540-530 Myr) sandstones, ...
Did I just put several kilometres of rock deposition and then incomplete erosion there, slap
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Downhill. Water flows downhill, and carries eroded sediment with it. Into the nearest ocean basin.
Then, the next time that basin got squeezed shut by colliding continents, this relatively soft, squishy new stuff got squeezed back up (there's probably a cooking analogy, but I can't compose one at the moment) until it flopped back over onto the approximate area it came from.
Lather,
It wasn't me (Score:4, Funny)
It wasn't me... I didn't take them. Nobody can prove anything.
I aint no geologistâ¦. (Score:1)
Incompatible (Score:2)
Outside the box (Score:3)
Probably (Score:1)
Life managed to cling on. (Score:2)
We are the Cling-ons.
Fraggle Rock (Score:2)
they were sold! (Score:2)
You came to the right place. (Score:2)
So, three good theories: (1) "snowball", (2) "erosion of the supercontinent Rodinia", (3) "confusion".
If there's anywhere this can be solved, it's /. We'll get back with you shortly. :-)
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You got me, I was lonely during pandemic and collected too many Pet Rocks. I'll put them back.
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While these individual words are arranged in a grammatical construct, they make no sense. "I collected too many rocks" (of any type) is not a valid sentence.
I've heard this story before (Score:2)
There are no missing rocks (Score:3)
It's all in our mind, or to be more specific most of us are walking around with rocks in our heads.
What is the mass of these "missing rocks"?
There are roughly 7.5 billion people on the planet and the average human head is 5kg. Most heads aren't solid rock, so I'm going to have to guess on this next part. I'll guess that our heads are about 2/3 rock, but this is not evenly distributed throughout the population. There are some with small pebbles and there are others who are solid granite.
So, roughly 37.5 billion kilograms worth of heads with 2/3 being rocky = 25 billion kilograms or 25 million metric tons of rock (~55.1 billion pounds, ~27.6 million US tons).
How much volume does that take up? Well, I guess it depends on how dense we are and the rocks in some people's heads are so very, very dense. Another site says 13 cubic feet per ton. I guess they mean US ton, since they're using cubic feet.
So to put into terms we can all understand
13 cubic feet = 0.37 cubic meters.
27,550,000 * 0.37 = 10193500 cubic meters
An Olympic swimming pool is 50 meters by 25 meters by 2 meters, so 2500 cubic meters.
Therefore, we humans are walking around with enough rocks in our heads to fill over 4000 Olympic size swimming pools!
In case that doesn't help, it would take up 5,096,750 square meters if there were no space at all between them.
On the other hand, this is only about 1260 acres. That's about 50% larger than Central Park or about 0.6% of the land area of Fort Hood in Texas or about 4 times the size of the National Mall in Washington DC.
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It wasn't me (Score:2)
Why? (Score:2)
I ate them.
They were stolen?? (Score:2)
Dang tourists will take anything for a souvenir.
Dang Aliens (Score:2)
Yeah.. It was probably filled with some mineral highly valuable to extra-terrestrials. And they took it. Now only a few every now and again come back to buzz our air craft carriers or such, looking for scraps of it left under the sea floor somewhere..
But seriously, that is an interesting mystery.. I'd like to know... These kinds of things keep me up at night wondering. However, I find that making up ridiculously pleasing answers quells the angry sheep and lets me sleep..
Stop looking under the streetlight (Score:2)
It could also be just an Ice Age where anything like volcanic dust that fell onto the moving glaciers simply kept marching off towards the ocean, carried it all there, and dumped it off the edge. The only question is, where? Finding the missing sediments under the ocean floor, from the same time period, might just give us a clue but you would need core samples to find it. If you are looking for it on land, you are not looking in the right place.
Reminds me of the old joke of the drunk looking for his car key
Re: (Score:2)
You wouldn't need to core - just regular drill cuttings are perfectly good for extracting datable mineral grains. Being sediments, any ages you get from zircons (yes, zircon can be a sedimentary grain too! - we use the zircon: apatite: magnetite ratios to distinguish sands sourced from Scotland versus those sourced from Iceland when drilling "West of Shetland")
I'd bet Loki was involved somehow (Score:2)
Sounds like his kind of mischief.
Re: (Score:2)
You're blaming geology with your poor literature search skills.
I grew up (geologically) on another example of this "Great Unconformity" phenomenon in NW Scotland (except, our example has at least two unconformities representing up to 50km of erosion, then up to about 8km of deposition, then between 10, 5 and 3 km of further erosion (resulting in thickness variations of several km, over a few km on the ground) and then the Cambrian came in.
Since then, I've worked dr