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Author Topic:   Chalk takes millions of years to form
Tangle
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Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


(3)
Message 1 of 57 (713262)
12-11-2013 11:10 AM


If you were new here and didn't know any better you could be forgiven for thinking that all of the earth's geology is contained in the Grand Canyon.
This is the geology of my home town on the south coast of England:
The White Cliffs of Dover - and those of my home town - are chalk. Chalk, according to wiki is:
The cliffs are composed mainly of soft, white chalk with a very fine-grained texture, composed primarily of coccoliths, plates of calcium carbonate formed by coccolithophores, single-celled planktonic algae whose skeletal remains sank to the bottom of the ocean during the Cretaceous and, together with the remains of bottom-living creatures, formed sediments. Flint and quartz are also found in the chalk
Chalk is useful stuff, you can cut the turf and make naughty pictures:
2. Cerne Abbas Giant — 180 ft tall
Also known as the Rude Man, the Cerne Abbas Giant in Dorset is carved into the side of a steep hill and formed by a 12-inch wide trench. The Giant with an erect penis wields a 120-ft knobbled club, and probably formerly held a cloak or animal skin in its left arm while standing over a disembodied head.
But chalk is also very old. My lot - and apparently most of the world's chalk - was formed in the late cretaceous period (66-100mya).
The chalk beds around here are about 400m deep and the highest is about 110m above sea level.
It takes about 1,000 years to build 1-10 cm of chalk (depending on type and condition). So if we started today, and use the fastest rate, it would take 4 million years to build my chalk cliffs.
I'm no geologist, but it seems to me that this single piece of geology is enough to prove that the earth is older than 6,000 years. Anyone care to put me right?
Edited by Tangle, : No reason given.
Edited by Tangle, : No reason given.

Life, don't talk to me about life - Marvin the Paranoid Android

Replies to this message:
 Message 3 by Stile, posted 12-11-2013 11:43 AM Tangle has replied
 Message 5 by ringo, posted 12-11-2013 11:54 AM Tangle has not replied
 Message 7 by New Cat's Eye, posted 12-11-2013 12:28 PM Tangle has not replied
 Message 8 by Faith, posted 12-11-2013 12:29 PM Tangle has replied
 Message 28 by RAZD, posted 12-11-2013 9:56 PM Tangle has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 4 of 57 (713266)
12-11-2013 11:52 AM
Reply to: Message 3 by Stile
12-11-2013 11:43 AM


Re: Chalkland Islands
Stile writes:
This geological chalk you're talking about. Is it the same as colloquial chalk? Like the stuff used by teachers in classrooms on chalkboards?
I reckon they would have been originally - the kids here take great fallen chunks of it and scrawl everywhere, of course - but apparently now they're :
" often made not from chalk rock but from calcium sulfate in its dihydrate form, gypsum. Chalk sticks containing calcium carbonate typically contain 40-60% of CaCO3"
If so, is there any "chalk shortage" coming about from all the teachers using it up... what with it taking so long to make more, anyway.
Nope. And anyway, pretty much all schools now use whiteboards with marker pens. Pity really, I suspect having a teacher throw a marker pen at you will cause more damage than chalk.

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 3 by Stile, posted 12-11-2013 11:43 AM Stile has seen this message but not replied

Replies to this message:
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Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 13 of 57 (713277)
12-11-2013 1:03 PM
Reply to: Message 8 by Faith
12-11-2013 12:29 PM


Faith writes:
A Floodist like me would hypothesize that the cliffs were like any of the thick strata anywhere on the earth, the result of the transportation by water of already-formed already-existent particles to their current location, and that before the Flood conditions were such that it didn't take so long for them to accumulate anyway. Any reason why this isn't possible?
Well, as Dr a says, even supposing that was possible, you still have to have many millions of years before your flood to manufacture the plankton and have it die and sink to the bottom.
But even if you had the coccoliths all there and ready before the flood, they had been geologically formed into ROCK, not dandruff, and wouldn't be going anywhere. (And btw, my cliffs are only 100 meters above sea level, but the chalk under the North sea is 1km thick.)

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 8 by Faith, posted 12-11-2013 12:29 PM Faith has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 14 of 57 (713278)
12-11-2013 1:44 PM
Reply to: Message 8 by Faith
12-11-2013 12:29 PM


This is apparently the correct creationist response:
Can Flood geology explain thick chalk beds? - creation.com

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 8 by Faith, posted 12-11-2013 12:29 PM Faith has replied

Replies to this message:
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 Message 16 by Faith, posted 12-11-2013 3:07 PM Tangle has replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 17 of 57 (713285)
12-11-2013 4:40 PM
Reply to: Message 16 by Faith
12-11-2013 3:07 PM


Faith writes:
Perhaps I'm just impatient but my computer is very slow these days and I'm back here to ask you if it's easy enough to put the idea into words yourself. Or maybe give me another link I can actually open. Thanks.
It's not opening for me either atm, it looks like their server isn't responding. it's too long and fanciful for me to reproduce it, we'll just have to wait.
As for the problem with transporting existing coccoliths that you expressed, because they would have been hardened into rock as they are in the cliffs, I keep seeing them described as "calcareous ooze" which doesn't sound like rock.
You've seen the picture of the cliffs, does it look like ooze to you? Clue, my house is built on it. Or are you saying that the ooze only hardened in the 4,000 years after the flood?

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 16 by Faith, posted 12-11-2013 3:07 PM Faith has replied

Replies to this message:
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 Message 21 by Faith, posted 12-11-2013 5:58 PM Tangle has replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


(4)
Message 33 of 57 (713330)
12-12-2013 5:55 AM
Reply to: Message 21 by Faith
12-11-2013 5:58 PM


Faith writes:
No, I'm not suggesting that chalk of the hardness of the cliffs could have been transported.
Ok. That means that before the flood there weren't enough coccoliths to cause them to solidify or there was enough but some magical force prevented it doing so.
I'm considering that perhaps where they collect at the bottom of the ocean that they are in that condition of "ooze" and might be transportable. Can you answer THAT thought?
Yes, as above. But a geological "ooze" isn't what we normally call an ooze, it's rock
Oozes. In case of marine sediments, ooze does not refer to a sediment's consistency, but to its composition, which directly reflects its origin. Ooze is pelagic sediment that consists of at least 30% of microscopic remains of either calcareous or siliceous planktonic debris organisms.
Also, you only have only 2,000 years to build enough ooze to form at least 400m of rock for a process we know takes 1,000 years to form a maximum of 10cm
Never mind, I think Dr. A did and it suggests that yes, they may have been in a transportable condition at the time of the Flood or some great number might have been.
Let's compare the two ideas:
1. What geologists say happened
The chalk cliffs are composed of the microscopic skeletons of various forms of plankton. These plankton live in the top layers of the ocean and when they die their skeletons which are composed mostly of calcium carbonate sink slowly to the bottom of the ocean and slowly build chalk rock.
When the layer of rock form, they combine with the bodies of bottom living organisms such as molluscs and shrimps which become fossilised.
Just to be clear, these skeletons - called coccoliths - are tiny, here's a scanning electron microscope's picture of one:
Can you begin to imagine how many of those you need to make my cliffs?
There are bands in the chalk formed of flints and quartz and other bits and pieces. This describes it better than I can:
Flints are a well known component of Chalk and they are present as nodular seams, tabular beds ann linings to fractures, and characterise the upper parts of the Chalk sequence. They comprises a random mosaic of quartz crystals, only a few microns in diameter, interspersed with minute water-filled cavities. The silica was derived from the dissolution of the siliceous skeletons of sponges and other organisms and has been redistributed in the form of nodules during several stages of crystallisation. The earliest precipitations of Flint occurred near organic remains such as burrow-fills or other decaying debris. Further accretion gave rise to either isolated nodules or layers of tabular flint. The preservation of uncompressed fossils such as Echinoids and Ammonites in flint indicates that the replacement commenced early in the lithification of the chalk. However, the presence of flint sheets along joints and faults shows that the quartz remained mobile and recrystallised during subsequent burial, folding and faulting. The flint beds closely parallel the bedding and are valuable tool in the correlation of the Chalk. Inside flints you can sometimes find a white or cream coloured soft powdery chalk inside flints. It is known to geologists as "flint meal". Fossils such as echinoids can be present within flints.
Traces of very fine grained quartz also occur throughout the Chalk, but overall comprise less than one per cent of the rock. At various levels clay material occurs as discrete seams or layers. Locally these may rest on minor erosion surfaces. Many of the marl seams which comprise both quartz and clay minerals such as Illite and Smectite provide persistent marker horizons which can be recognised regionally.
Phosphate minerals are widespread in the Chalk and localised concentrations occur as impregnations and coatings on the sediments, or as pelletal concretions. It is often most conspicuos where depostion ceased for a time and the upper surface of the sediment became compacted (hardgrounds). Glauconite occurs in minute quantities throughout the Chalk, but is concetrated at some horizons (commanly at hardgrounds again) as detrital grains or as encrustations or replacements. Finely disseminated pyrite is also common and sometimes pyrite concretion are present with radiating crystals.
At some horizons the clay content of the Chalk is higher, particularly at the base where in England the Chalk Marl was deposited. This grey and relatively impermeable Chalk was the main tunnelling horizon for the Channel Tunnel. Higher in the Chalk the Plenus Marl and thinner marls seams occur. The Chalk often shows a distinctive cyclicity, plus it can be both massive at some horizons and nodular at others.
The chalk is not all the same showing time passing. It also shows purity, meaning that the seas were clear of debris and a long way from land:
The Chalk often shows a distinctive cyclicity (on a 1m or so scale) which has been linked to variation in the climate at the time of deposition (Milankovitch cycles).
The lack of coarser clastic material in the majority of the Chalk, with quartz being most common in the clay size grade, indicates clear seas with minimal eroded products being transported from the landmasses at the time. Indeed, much of the clay sized quartz and clay may be airborn and of volcanic origin.
Chalk is also only formed in warm (20C) water - I can confirm that the waters here are NOT 20C. So it built up during the long periods of much warmer climate millions of years ago.
The climate was much warmer when the chalk formed than it is now. We know that the water was warm because of the composition of the rock. The billions of cocolithophores which made up the chalk only survive in warm, relatively pure water, so this sea must have had these conditions (Gallois 1995). Calcareous oozes can only form in water less than 4500 meters in depth, so the chalk was not formed in any sort of deep sea environment (Garrison 2002). This chalk had to have been deposited in water approximately 200 to 300 meters in depth because this is the only way the small, delicate cocolithophores would have been preserved (Melville 1982).
The chalk is thought to have formed on the outer edge of a continental shelf, the biggest in any Jurassic sea found along the Southern Coast of England (Melville 1982). At this point in time England is thought to have been situated at a more southerly locationthan at present which would have augmented the already higher temperatures (Lovell 1977).
These conditions lasted a long time:
The Chalk Sea lasted for approximately 30 million years (Ensom 1998) which was enough time for billions of coccolithophores shells to be deposited on the seafloor (Gallois 1995). One thing that makes the chalk so unique is the near absence of terrigenous material (Chatwin 1960). This is due to the fact that land was a great distance away from the depositional environment (Chatwin 1960). Also, the land had to have been fairly flat and would not have had a good mechanism with which to bring detrital matter out to the open sea (Rayner 1967). The chalk is especially unique because it has the greatest outcrop area of any formation in England (Rayner 1967).
There are three identifiable layers in the chalk showing a gradual change in conditions over time:
Within the chalk there are three subdivisions, the Lower Chalk, the Middle Chalk, and the Upper Chalk. The contacts between these layers are gradational, indicating a gradual change in environment (Wright 1981). The layers of chalk can be identified by their lithological characteristics, as well as the fossils they contain (Chatwin 1960). Over time, the water in the area became deeper and the chalk became purer (Gallois 1995). Only the Upper Chalk has many economic uses, it writes readily on wood, and is fit for the cooper, for whiting, for lime, and for manure (Wright 1981). The Middle Chalk is noted as only being fit to use on highways (Wright 1981). Overall however, the chalk is hard enough to be a significant building tool but only on the local level because it is so much softer than the surrounding limestone (Ensom 1998).
If you look at the chalk cliffs themselves, you see thin (6"+) layers of flint stones the size of your hand +/-. These flints can only form after the the layers of microscopic chalk have formed. The thin lines here are the flints:
Close up:
The flints are formed from silicates deposited from living sponges and silicate plankton which resolve and re-precipitate.
(You obviously realise that if all this could be churned up in your flood and allow to settle - it couldn't chalk is rock - all the flints would be at the bottom, not layered as they are.)
The flints, btw are not little pebbles, we build walls and houses out of them here:
All of this tells the same consistent story of very long periods of time and different climates.
2. Faith's view
Well you don't have one really, you're trying to make one up as you go along but you're trying to imagine how that depth of coccoliths can be built up either
a) in the 2 thousand or so years before the flood in an un-solidified state, then churned up by the flood and allowed to settle in the 4,500 years after the flood. Note that for this you also have to explain the layers of flint that would not settle into neat lines about the less dense coccoliths, why the coccoliths are not rock, why there are three types of chalk signifying differing climates, how the water was very clear allowing pure chalk to form and how the water was at 20C.
b) the chalk formed after the flood. For this you have to explain how the rate of between 1-10cm per thousand years changed to something many, many times faster. Science says it takes 4m years minimum, you have a couple of thousand. (I say a couple of thousand to be generous, because we've been using flint to build stuff for as long as that here.)
You also have to shift it from where it was formed - in a warm, shallow ocean far away from the land which would pollute it to where it is now - in my back garden, 100m above sea level.

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 21 by Faith, posted 12-11-2013 5:58 PM Faith has not replied

  
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