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Author Topic: Is Earth Recycling it's surface and Wiping the Slate Clean?  (Read 12283 times)

Offline Andrew K Fletcher

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The Ultimate Recycling Project

Wiping the Slate Clean.


Questions:

1.

How long would it take to completely erode a coastline so that for example Great Britainís land surface has been wiped clear of all traces of humanity? There is a huge amount of evidence to support the view that once great thriving cities became submerged.

2.

Given the land mass turnover of tectonic plate movements, how long would it take for the flow and return of rocks to the surface to completely remove all traces of humanity?

3.

Given the present sterile surface of Lanzarote in the Canary Islands, following the huge recent volcanic activity that has completely transformed the island into predominantly volcanic debris and ash, How long would it take for the same volcanic activity to transform the surface of Great Britain.

Lanzarotes "Big Bang" started on September 1, 1730. By April 6, 1736, one of the worlds most devastating and long--lived volcanic eruptions had finally come to an end.During those six horrifying years, the area around what is now the Timanfaya National Park -- Lanzarotes Fire Moutains -- was transformed from an agricultural zone of quiet villages with exuberant vegetation and extensive vineyards, into a deadened stark landscape, a monstrous heap of volcanic debris and a bleak reminder of the totally unforgiving face of nature.
Before the colossal volcanoes erupted, the old Vegas de Timanfaya boasted some of the islands most fertile terrain. Cereals swayed gracefully in the wind, and herds of cattle grazed on the grassy meadows of the Vegas. Springs, like those in Ortiz and Miraderos, were dotted around the landscape which literally blossomed with abundant crops.All that came to an end on a September night more than 250 years ago when molten lava came teeming out of Timanfayas countless craters.Mountains rose and fell like gigantic waves and lava spewed out for six years, practically non--stop, punctuated by relatively short periods of calm.All the surrounding villages were totally destroyed including Tingafa, Mancha Blanca, Maretas, Santa Catalina, Jaretas, San Juan, Pea Palomas, Timanfaya, Rodeo and Mazo.
Entire villages and homes either disappeared under a torrent of red--hot lava or were reduced to mere ashes. Volcanic ash rained on other nearby villages, destroying in part, La Asomada, Iquadez, La Geria, Mozaga, Lomo de San Andres, San Bartolome, Conil, Masdache, Montana Blanca and Guatisea. Text written by: Tony Layton
http://www.lanzarote-guide.com/en/volcanoes




Photographs from Lanzarote showing evidence of farming regeneration 250 years after the Island errupted.
The Circular Cafe poised on top of the active volcano uses the volcanic heat to barbecue food for the customers.
But Lanzarote shows how the Earth can remove all traces of human and animal activity. Imagine landing in Lanzarote immediately after the lava stopped flowing and the volcanoes became silent. Looking around it is difficult to imagine how it must have been prior to it's recent violent transformation.

4.
How long would it take for the Sahara Desert to expand and smother everything in itís path and engulf an entire African continent, given itís impressive progress so far?

Andrew K Fletcher



« Last Edit: 20/04/2008 17:58:34 by Andrew K Fletcher »


 

Offline Andrew K Fletcher

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #1 on: 21/04/2008 10:43:03 »
I need your help here guys, trying to show that it is probable that the Earth is much older than the current thinking and that the Earthís surface is constantly being wiped clean of all traces of activity, burying the evidence beneath oceans, deserts and rock formations. Given sufficient time anything is possible and this is the point raised on this thread. When we measure what we see as evidence, are we merely measuring the evidence of our own timescale?

I have chosen desertification as one example to show how shifting sands can engulf and obliterate all signs of previous inhabitation within a very short timescale as demonstrated by the expanding Chinese Desert.

Lanzarote gives us another even more rapid model for wiping the surface clean, and lets not forget that this is anything but an isolated case given what happened in Italy:
Pompeii is a ruined and partially buried Roman city near modern Naples in the Italian region of Campania, in the territory of the comune of Pompei.
It, along with Herculaneum (its sister city), was destroyed, and completely buried, during a catastrophic eruption of the volcano Mount Vesuvius spanning two days on 24 August 79 AD.[1]
The volcano collapsed higher roof-lines and buried Pompeii under many meters of ash and pumice, and it was lost for nearly 1700 years before its accidental rediscovery in 1748. Since then, its excavation has provided an extraordinarily detailed insight into the life of a city at the height of the Roman Empire.
Another method this planet has of reminding us that our marks on this planet are not indelibly etched forever is mudslides, The 1999 Vargos disaster The unusually strong storm in December 1999 approximately 911 millimeters of rain fell in just a few days, causing soil instability and flow of debris. The State had a similar disaster in 1951,
And then there are flash floods like the Boscastle Flood - 16th August 2004.


http://www.earth-policy.org/Updates/Update26.htm
China Losing War With Advancing Deserts

Lester R. Brown

China is now at war. It is not invading armies that are claiming its territory, but expanding deserts. Old deserts are advancing and new ones are forming, like guerrilla forces striking unexpectedly, forcing Beijing to fight on several fronts. And worse, the growing deserts are gaining momentum, occupying an ever-larger piece of China's territory each year.

Desert expansion has accelerated with each successive decade since 1950. China's Environmental Protection Agency reports that the Gobi Desert expanded by 52,400 square kilometers (20,240 square miles) from 1994 to 1999, an area half the size of Pennsylvania. With the advancing Gobi now within 150 miles of Beijing, China's leaders are beginning to sense the gravity of the situation.
 

Offline Andrew K Fletcher

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« Reply #2 on: 21/04/2008 11:19:03 »
Rates of motion
We can measure how fast tectonic plates are moving today, but how do scientists know what the rates of plate movement have been over geologic time? The oceans hold one of the key pieces to the puzzle. Because the ocean-floor magnetic striping records the flip-flops in the Earth's magnetic field, scientists, knowing the approximate duration of the reversal, can calculate the average rate of plate movement during a given time span. These average rates of plate separations can range widely. The Arctic Ridge has the slowest rate (less than 2.5 cm/yr), and the East Pacific Rise near Easter Island, in the South Pacific about 3,400 km west of Chile, has the fastest rate (more than 15 cm/yr).
http://pubs.usgs.gov/gip/dynamic/understanding.html
 

Offline LeeE

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #3 on: 21/04/2008 18:44:19 »
While the world's surface is constantly changing I think it's far from totally recycling itself.  AFAIK the age of the Earth is around 4.5 billion years and there's still some exposed rock around that dates from around 3.8 billion years ago.  The oldest zircons found on the surface date from around 4.3 billion years ago.  This means that in 4.5 billion years the Earth has been around it hasn't managed to recycle everything even once yet.  On smaller scales there have certainly been some huge changes - the Deccan Traps spring to mind - but on a global scale the rate of change and recycling so far is very slow and on a tiny scale, even if our personal perception suggests otherwise.
 

Offline Andrew K Fletcher

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« Reply #4 on: 21/04/2008 19:00:02 »
Hi Lee and thanks for the input.

Maybe we should be saying that the oldest substance we have found so far is estimated to be around 4.3 billion years based on? Zircons require a considerable amount of pressure to make right? Whatever created that pressure must have been around far longer than the zircons!
 

Offline LeeE

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« Reply #5 on: 21/04/2008 19:29:36 »
Ah - because something has required immense pressures and temperatures to create, and has existed for a long time, it doesn't mean that it takes a correspondingly long time to make it and neither does it mean that whatever caused those high temps and pressures had to be around for a long time before then.  As soon as the conditions are right, it will occur.

Although having said that, I don't know how zircons are formed - I'm just assuming that very high temps & pressures are required.  Is zircon a phase-change material e.g. like carbon into diamond?
 

Offline Andrew K Fletcher

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« Reply #6 on: 21/04/2008 21:25:51 »
if the Earth is 4.5 billion years old, is not growing or shrinking we can presume that events on Earth must be relatively reliable. If we take the 15 cm's per year rate of tectonic motion in the East Pacific Rise, multiply it by 4.5 billion years and divide it by 100k we get 675000 kilometers of movement, divide this by the land surface of the tectonic plate that is moving and we should see that there is ample scope for completely erasing the Earths surface.
 The earths circumference for example is (40,008 km). divide the movement by the Earth's circumference and we get   16.871625674865 times the Earth's circumference has been completely wiped clean.

Now, we know that all of the tectonic plates are not moving by 15cm's per year, but we do know that one of them definately is and that means that this particular plate has been recycled completely many times in the 4.5 billion years or so curently thought to be the age of the Earth, meaning that every single rock on the surface has been pulled down towards the core, possibly turned into molton rock and brought back to the surface a huge number of times.

 

 

Offline rosy

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« Reply #7 on: 21/04/2008 23:16:45 »
Quote
if the Earth is 4.5 billion years old, is not growing or shrinking we can presume that events on Earth must be relatively reliable.

But we can't presume that at all, I don't think... as I understand it the assumption is that the earth would initially have been molten all the way to the surface and subsequently cooled and is still cooling (as the proportion of radioactive isotopes decays and so the rock of itself generates less heat), so the rate of flow doesn't necessarily have to have been anything like consistent over time, it could have slowed considerably over the billions of years. So more of the earth's surface might have been "wiped clean" than you'd think.

However, you also need to take account of the fact that as continental shelves meet they won't both get destroyed, whilst one plate is forced under the other, and so any clear picture of what was there before will be destroyed, the upper layer ploughs on over the top without being chewed up anything like so much.

By the way, why do you want to show the earth's older than currently supposed?
 

Offline Soul Surfer

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #8 on: 22/04/2008 07:40:08 »
The earth's surface is recycling due both to erosion and subductiuon.  It was realised right at the start of geology that there must be recycling processes because it can be calculated from erosion rates today that erosion would completely flatten the earth's surrface in a few tens of millions of years

Good evidence of this is provided by the lack of impact craters. Both new and old surface can come back to the top.  Old sedimentary rocks are usually metamorphised in that they have been taken deep down into the earth's crust and subjected to intense heat and pressure. 

The good fossil record only goes back about 500 million years  partly because before that things did not have bony skeletons and partly because rocks much older than this have been "recycled"
 

Offline Andrew K Fletcher

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« Reply #9 on: 22/04/2008 15:29:54 »
Thank you Rosy

The Earth is undoubtedly constantly changing. However, given the timescales of change involved, any interpretations, including my own must be presumptuous due to the lack of evidence dating back further than our presumed earliest rock found. So for our interpretation of these samples to be anywhere near correct, it must relate only to the rocks that we have found and must not be extended into trying to predate the Earth.

Now, if as you and others have stated that the Earth was molten and is now cooling, then the rate of recycling on a cooling planet must have been far more aggressive than today, and as you say we should be taking into account in our estimate of global recycling a vastly accelerated rate of tectonic plate movement by todayís comparisons.

Yet, if we look at the moons surface it appears to be much slower in recycling its surface, and as Soul Surfer states, erosion must also be taken into account and could itself given sufficient time could have completely recycled the Earthís surface many times over, without the help of tectonic plate movement.

In fact, there is very little evidence to suggest that the earth was molten to begin with other than the heat coming from the core. What if a huge number of zeroís are missing from the true age of the planet? How many times could the surface have been wiped clean? What hidden secrets are yet to be found inside rocks and crystal?

You ask why do I want to show that the Earth is much older than currently supposed.

Because the truth in science is all that really matters, without truth we are left with a belief in the hope that it may be true.

Thank you for your input Soul Surfer. I agree wholeheartedly with what you have said. And in particular the point that rocks are metamorphosed under great pressure and heat before being thrust back to the surface as more rocks are dragged down towards the core. Some of these rocks can be heard shattering like gun shots in the extreme hot and cold rapid temperature changes in deserts, more evidence to support the erosion process.

Suppose, we built a huge city by the side of the ocean with massive stone columns and glorious mosaics and archways and then watched it get slowly engulfed by the ocean to the point where it is no longer visible from the surface. Add a good sprinkling of sediment and coral and a whole city could vanish from view given just a few thousand years. So given a few million years what else could be submerged below the waves? In fact given enough time everything we see before us today will be wiped from the face of the earth without a trace. Remember what happened during the tsunami in Banda ache? 
http://youtube.com/watch?v=00mqLMdKqbc&feature=related
« Last Edit: 22/04/2008 15:40:09 by Andrew K Fletcher »
 

Offline Bored chemist

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« Reply #10 on: 22/04/2008 19:25:01 »
"In fact, there is very little evidence to suggest that the earth was molten to begin with other than the heat coming from the core. What if a huge number of zeroís are missing from the true age of the planet?"
Just adding one zero would make it older than the observed universe.
Since the earth isn't that old it seems that the upper bound to the answer to "How many times could the surface have been wiped clean?" is "Maybe 4 at a push".
 

Offline Andrew K Fletcher

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« Reply #11 on: 22/04/2008 21:51:08 »
BC thanks for the input

Adding 1 zero will not alter the age of either the planet or the universe, al it will do is alter our perception of how old we think the universe and indeed our planet is.

Personally, I doubt that we are guessing anywhere near the true age of this planet, let alone the universe. We are probably closer to estimating the arrival time of visitors from another planet than guessing the age of the Earth.. I disagree wholeheartedly about placing restrictions on science. Science knows no boundries.
« Last Edit: 22/04/2008 21:52:54 by Andrew K Fletcher »
 

Offline Bored chemist

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« Reply #12 on: 23/04/2008 19:48:59 »
You might be guessing the age of the plannet. The rest of us are measuring it. For example we know the basic physics of how the sun works. Nothing will alter the age of the earth, but putting another zero on the estimate will alter that estimate. For the earth to be one zero older ie rougly 45 billion years it would need to be considerably older than the sun. So what adding a zero does is alter the estimate from possible to impossible.
That seems to me to be an entirely reasonable boundary to put on science. Don't consider things that simply don't agree with the evidence.
 

Offline Andrew K Fletcher

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« Reply #13 on: 23/04/2008 20:08:27 »
What if the Earth did not begin as a molten Mass?
What if there was no rapid cloud of dust being combined to cause a solid homogenous mass that became molten then gradually cooled down?
What if the sun is the result of a planet getting to big to remain stable and the intense gravitational field from such a massive planet generated sufficient energy to turn the planet into a sun?
What if we really donít have a clue as to how the sunís radiation is generated?

Guessing the age of the sun is lunacy. Saying you can measure the age of the sun is simply untrue and beyond the science boundaries.

Saying you can guess / measure the age of the universe based on our puny life time and every event that has happened since our great great great grandparents were born will never bring us close to the real answer.

It is arrogance that tries to put a number against the age of the universe, not science. I am quite content with the Universe being the Universe for eternity, always will be there and always was there.

The only changes are those made as planets expand, explode eradiate and erode Heating up and cooling down is just the way it is with planets and the way it always will be.

Do I trust a man or an organisation that asks me to believe they have put an accurate date on the birth of a planet? What planet are these people from?
 

Offline Bored chemist

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« Reply #14 on: 23/04/2008 21:02:49 »
"It is arrogance that tries to put a number against the age of the universe, not science. I am quite content with the Universe being the Universe for eternity, always will be there and always was there."
No, it's not arrogance, it's observation.
You may have noticed that it goes dark at night.
That is proof that the universe is finite in time or extent- it doesn't tell you which. (actually there's a third possibility- our local bit of the universe is different from the whole (infinite) rest of it. Believing "my bit of the universe is special" seems a lot more arrogant to me)
The red shift of spectra from distant objects shows that they are moving away from us. If you think about that it means that, in the past, they must have been close to us. In the limit that gives you the big bang.
Frankly, if you are content with a belief that doesn't agree with the observations that's fine, but I don't think you should be posting it on a scientific site.

"Do I trust a man or an organisation that asks me to believe they have put an accurate date on the birth of a planet?"
If he can show you his data and the observations to back it up why wouldn't you beleive it?

"What planet are these people from?"
One where they understand that making deduction from observation is a usefull way to get on in the world.

OTOH should I trust a man who says
"The only changes are those made as planets expand, explode eradiate and erode Heating up and cooling down is just the way it is with planets and the way it always will be"
Just after saying thst he thinks it's impossible to know what happened in the past?
You can't have it both ways. Either we know  (based on the evidence) or we don't (in spite of that evidence).
If we don't know then you have no basis for making that statement.

« Last Edit: 23/04/2008 21:07:49 by Bored chemist »
 

Offline Andrew K Fletcher

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« Reply #15 on: 23/04/2008 22:29:20 »
We can go on splitting hairs about what is right and what is wrong with our assumptions but the fact remains these objects we are debating are a long way off for us to make sense,

Let me give you a for instance. Say we have a huge planet far of in another galaxy that reached critical mass and turned into a sun, and say that initial explosion or may even have been a gradual warming up to reach the suns temperature who knows? Lets say this event was an explosion of a massive magnitude and prior to ignition it had a number of planets, moons and asteroids orbiting its huge mass. The explosion sends the planets off on a trajectory away from the explosion, possibly because the planets gravitational field has changed also into a repelling force from an attractive force thrusting and releasing the planets to head off across the universe.

Now, let say a scientist takes his spectrum analysis data based upon targeting these planets that have been sent off at a considerable velocity and in doing so assumes that the Universe must be expanding because these planets are getting further and further away from ours? Possibility?

My point here is that there may be another perfectly logical answer as to why distances can be measured as changing between tow objects many light years apart.

Hereís another. Maybe the planets are in orbit around another galaxy, maybe the galaxy is in orbit around another galaxy. Maybe our own galaxy is also in orbit around another giving the appearance that the objects are rapidly moving away from our own planet.

Nothing is carved in stone in space science BC. We simply cannot gather sufficient data in our own puny lifetimes to evaluate all the possibilities.

Admittedly we can give it our best shot, but it should be seen as that and nothing more.
 

Offline Bored chemist

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« Reply #16 on: 24/04/2008 20:20:07 »
"The explosion sends the planets off on a trajectory away from the explosion, "
The law of conservation of momentum requires that the gentre of gravity of the bits after the explosion follows the same path as the planet (or whatever) did before.
So, while there would be bits flying away from us, there would be bits flying towards us too (unless the whole object was receding from us before the explosion in which case the big bang still looks good).
The receding bits would be red shifted, the bits coming towards us would be blue shifted and the bits flying perpendicular to our line of sight wouldn't be shifted at all.
So, overall, you would get a broadening of the spectral lines, not unlike the dopler broadening seen in more conventional spectroscopy, but not the red shift we see in distant stars.

Also, red shifts have been observed for a whole lot of stars- some old, some young. We might not have been here for long-  I fully accept that our few millennia is a flash in the pan on the cosmic scale- but we can still observe billions of years worth of data.

If we are in orbit round something then we would be moving towards some things, but away from others. The red shift we see is the same in every direction- so it can't be that.
One thing is "carved in stone" for space science, just like any other science. If a theory doesn't tally with the facts then it's time to get a better theory.
 

Offline Soul Surfer

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« Reply #17 on: 25/04/2008 10:00:22 »
Andreew I agree that we have to gather evidence and give it our best shot abut there is a lot of evidence from several different sources that set the generally given dates.  You may want this not to be true and prefer your own particular theories for some reason but this does not affect the evidence.  Acceptring thngs that you do not like because if an overwhelming amount of evidence is good science.  Just saying that everyone else is wrong is bad science. OK it is worthwhile revisiting fundamentals from time to time but you dont get science by just wanting something to be that way.
 

Offline Andrew K Fletcher

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« Reply #18 on: 20/05/2008 15:56:20 »
Evidence is all surface based! Measure the age of the molten core and then you will get an idea of the true age of the Earth. Measure some magma that has just solidified on the surface and see what the age of the magma is? Of course we canít do that can we because the magma would show up as a new sample relating to the volcanic event. Which proves we cannot date the Earth from Rocks found on itís surface or below itís surface for that matter. China has just experienced an earthquake. Some of the buildings that were once standing probably had dates of when they were built. Now the plaque is on the floor in the rubble and new buildings will be built to replace the ones that collapsed, with fresh dates of when the new buildings were erected. In a few hundred years time, people could find the plaques with the dates from the new buildings in a pile of rubble.

We cannot measure any rock and guesstimate the Earth's age from it. So if we have not got the date of the rocks to rely on what do we have left in our arsenal of Guessometers? Setting the foundations for science in stone will guarantee only that some day that same stone will be wiped clean and turned into Pumice where it will reside temporarily on the surface once more.

The Dating Game
Appendix to Marvin Lubenow, Bones of Contention (Grand Rapids: Baker, 1992, 1st ed.), pp. 247Ė266*
by Marvin Lubenow
http://www.answersingenesis.org/docs2006/0816dating-game.asp
 

Offline Bored chemist

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« Reply #19 on: 20/05/2008 19:29:44 »
"Evidence is all surface based!"
no it isn't, there are seismic surveys that look deep into the earth. Surveys of the mafnetic field tell us about the depths too.
"Measure some magma that has just solidified on the surface and see what the age of the magma is? Of course we canít do that can we because the magma would show up as a new sample relating to the volcanic event. "
No again, there are theoretical bases for predicting th einitial concentrationa of different isotopes- notably of uranium . These can be used to date magma. It turns out to be the same age as the earth.
"We cannot measure any rock and guesstimate the Earth's age from it. "
yes we can, and to the nearest order of magnitude, we dont need to anyway. The earth isn't older than the universe- roughly 15GY. It must be older than the oldest rocks- roughly 4GY so, if you call it 10 billion years you can't be out by more than about 5 billion.
"Setting the foundations for science in stone ..." nice soundbite, but the foundation of science is observation.


 

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« Reply #20 on: 24/05/2008 11:56:52 »
Interesting thread - but is there an underlying 'elephant in the room' that is "how long would it take to eliminate all traces of human activity"?
If there was then a good starting place would be the next glacial which could effectively sterilise a good deal of the 'civilised' west.
It's easy to forget that we're in an interstadial that has already gone on for a condsiderable time.
 

Offline Bored chemist

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« Reply #21 on: 24/05/2008 13:18:59 »
"how long would it take to eliminate all traces of human activity"?
The Earth will have anomalously high levels of plutonum and such like for a while.
If some disease suddenly wiped us out, nature would erase us prety well - the pyramids and stonehenge sugest that we would still leave a mark in 5 or 10 thousand years. Other things might last a bit longer.
The lack of fossil fuels might survive as evidece for a long time and the radioisotopes from nuclear reactors would take a long time to decay back to the levels that were present before nulear reactors and bombs were made. With really good analysis you could probably still spot us after a million years.
 

Offline Andrew K Fletcher

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« Reply #22 on: 26/05/2008 15:51:00 »
Ironically our corpses and the decay of everything that lived could well become the fossil fuels of tomorrow.

I wrote a paper on the pyramids that stated the shape of them was designed so that they could resist the drifting sands and remain visible long after the people that built them abandoned the desert soils or perished beneath them. The hieroglyphics remained as a warning to those who impoverish their soils, showing farming practices, fishing, hunting and indeed many deaths.

Their lifestyles totally unsustainable remain as a pictorial account of the folly of growing monoculture crops to feed a workforce and armies. Perhaps one day we will see the writings in the sands of time.

"how long would it take to eliminate all traces of human activity"?
The Earth will have anomalously high levels of plutonum and such like for a while.
If some disease suddenly wiped us out, nature would erase us prety well - the pyramids and stonehenge sugest that we would still leave a mark in 5 or 10 thousand years. Other things might last a bit longer.
The lack of fossil fuels might survive as evidece for a long time and the radioisotopes from nuclear reactors would take a long time to decay back to the levels that were present before nulear reactors and bombs were made. With really good analysis you could probably still spot us after a million years.
 

Offline Bored chemist

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #23 on: 27/05/2008 11:44:49 »
The shape of the pyramids is also the easiest shape to make, particularly if you want to make it big. Ask any mountain. If they were concerned just with the longevity of these monuments they would have made them all the same but some are stepped or bent.

If they noticed that their farming practice was screwing up their environment, wouldn't it have made more sense to change that practice rather than building bloody great piles of rocks?
It's an odd coincidence that, having decided to leave a warning to future generations of the folly of their ways they then chose to bury their kings (together with significant wealth) in them.
Sorry, but I reccon these were monuments to the power of the rulers of the day- not a warning of their mistakes- after all they continued to build pyramids for generations- that would have been long enough to change policy.
(they made pyramids for roughly a thousand years
http://en.wikipedia.org/wiki/Egyptian_pyramids
Just think how we have changed agriculture in that time.)

Also, you might like to tell us about populations that don't make monuments to their dead leaders.
http://www.nps.gov/moru/
http://en.wikipedia.org/wiki/Albert_Memorial

The idea that the pyramids were a warning to later generations doesn't add up.

 

Offline Andrew K Fletcher

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #24 on: 28/05/2008 20:15:38 »
The bloody great piles of rocks had to be built using manpower. Manpower requires feeding. Grasses were grown to fuel the buildings and this ultimately led to their demise. Same has happened all over the world where monuments lay deserted.

The real wealth was not the gold and silver found in the death chambers. It was the soil that these foolish people watched blow away in the wind that was the real wealth.

When the people became hungry, (and they became malnourished born out by the bone deformities and evidence of poor diet) They could no longer build these follies and abandoned the impoverished soils.

My guess is that there are many more ancient cities buried beneath the shifting sands of the Sahara and dried up river beds viewed from satellite could lead us to some pretty amazing discoveries.

We too build monuments and massive concrete structure for people to live in. We too have impoverished and neglected our soils. We watch as the deserts expand and engulf the surrounding areas and pretend that they are not really growing and the tropical rainforests are not really shrinking and all is perfectly normal, and yet even now we are beginning to see that the soils are unable to maintain the degradation we inflict upon them.

You may be right and these were built simply as a monumental defiance against nature. We perhaps will never really know. But they still stand as a witness to the folly of overexploiting our fragile environment.
 

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Is Earth Recycling it's surface and Wiping the Slate Clean?
« Reply #24 on: 28/05/2008 20:15:38 »

 

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