[_ Old Earth _] Carbon 14 Dating

[Barbarian]

How exactly do scientists “know” varves are really 'annual events' and not diurnal?

The ones they sample from are still forming annually, two layers a year. One light, one dark. And it would be astonishing to have that much sediment forming every day. Hundreds of times faster than any measured rate.

 

[zeke]

The ones they sample from are still forming annually, two layers a year. One light, one dark. And it would be astonishing to have that much sediment forming every day. Hundreds of times faster than any measured rate.

Do scientist really "know" these 'annual events' happened annually over millions of years or were there catastrophic events in the past that could have altered these so-called 'annual events'.

...when Mount St. Helens*erupted in Washington State it produced 25 feet of finely layered sediment in a single afternoon! Other such catastrophic events such as the Flood of Noah could also imply the action of laying down many layers quite rapidly within a year time-frame. Thus even millions of layers could be formed in just a few years.

creationwiki.org ​

 

[Barbarian]

Do scientist really "know" these 'annual events' happened annually over millions of years

Yep.

or were there catastrophic events in the past that could have altered these so-called 'annual events'.

Not unless they could cause two summers and two winters to happen in a single year, and magically produce all the pollen only during the summers.

...when Mount St. Helens*erupted in Washington State it produced 25 feet of finely layered sediment in a single afternoon!

No varves, though. I've been there. And the layers are mere lamina, not varves.

Other such catastrophic events such as the Flood of Noah could also imply the action of laying down many layers quite rapidly within a year time-frame. Thus even millions of layers could be formed in just a few years.

There are examples of hundreds forming (millions are out of the question, because it requires no turbation). But no varves can be formed that way.

And even if there was some magic that might do it, you still have to explain how it went millions of times faster in the past, and then slowed down to once a year just when we showed up to watch it.

Why not just accept that God did it the way He did it?

 

[zeke]

There are examples of hundreds forming (millions are out of the question, because it requires no turbation). But no varves can be formed that way.

You still haven't answered the question - how do scientist really "know" these 'annual events' happened annually over millions of years and were not affected by catastrophic events in the past? Aren't they simply assuming? Assumptions really don't prove anything - do they?

 

[lordkalvan]

You still haven't answered the question - how do scientist really "know" these 'annual events' happened annually over millions of years and were not affected by catastrophic events in the past? Aren't they simply assuming? Assumptions really don't prove anything - do they?

Nope, but evidence does the trick.

 

[zeke]

Nope, but evidence does the trick.

Then present it. Present evidence that Uniformitarianism is the correct assumption.

 

[lordkalvan]

Then present it. Present evidence that Uniformitarianism is the correct assumption.

By this, do you mean that want to examine the evidence that demonstrates varves are seasonally deposited, annually recurring laminae? A good place to start is Mia Tiljander's paper, Holocene sedimentary history of annual laminations of Lake Korttajärvi, central Finland. Would you like to discuss the evidential implications of this paper? I can provide you with the relevant link.

 

[zeke]

By this, do you mean that want to examine the evidence that demonstrates varves are seasonally deposited, annually recurring laminae?

Can you provide evidence that geological uniformitarianism is the correct assumption? Does Mia Tiljander assume uniformitarianism? You do understand the concept of uniformitarianism - right?

 

[lordkalvan]

Can you provide evidence that geological uniformitarianism is the correct assumption?

We are discussing the evidential implications of varves. Do you wish to pursue that discussion or not?

Does Mia Tiljander assume uniformitarianism?

I would not presume to speak for Mia Tiljander. If you like, I can provide you with her university email address and you can politely ask her yourself; she may or may not reply.

You do understand the concept of uniformitarianism - right?

Why would you suppose I don't? Do you understand what informs it and how modern geology has adapted its understanding of the processes that shape Earth in the light of advances in knowledge and understanding?

Uniformitarianism has been a key principle of geology, but naturalism's modern geologists, while accepting that geology has occurred across deep time, no longer hold to a strict gradualism.

Source: http://en.wikipedia.org/wiki/Uniformitarianism

The understanding is that, absent evidence to indicate otherwise, past geological action was like present geological action, as indicated for example by plate tectonics and orogeny.

So do you wish to examine the evidential basis that underpins an understanding of what varves signify, as reflected in the paper I have referred to, or do you wish to avoid addressing the question at all?

 

[zeke]

So do you wish to examine the evidential basis that underpins an understanding of what varves signify, as reflected in the paper I have referred to, or do you wish to avoid addressing the question at all?

I would like to exam your evidence from science (if you have any) that proves the uniformitarian assumption that millions of varves represent millions of years. Do you have such evidence?

 

[Barbarian]

I would like to exam your evidence from science (if you have any) that proves the uniformitarian assumption that millions of varves represent millions of years. Do you have such evidence?

No assumptions there. Initially, it was thought that they were some kind of weird rhythmites or other kind of laminae. Only after considerable investigation did it become clear that they were seasonal laminae that showed two alternating layers per year.

During fieldwork in 1878, De Geer noticed that the appearance of laminated sediments deposited in glacial lakes at the margin of the retreating Scandinavian ice sheet at the end of the last ice age, closely resembled tree-rings. In his best known work Geochronologia Sueccia, published in 1940, De Geer wrote "From the obvious similarity with the regular, annual rings of the trees I got at once the impression that both ought to be annual deposits" (1940, p.13).

While this observation was not new, De Geer was the first geologist to exploit its potential application. De Geer called these annual sedimentary layers varves and throughout the 1880s further developed his theory, publishing a brief outline of his discovery in 1882, which he followed with a presentation to the Swedish Geological Society in 1884. It was not until 1910, at the International Geological Congress, that De Geer's pioneering work reached the wider international scientific community.
Wikipedia

While varves were not useful for worldwide climate correlations as De Geer had hoped, they are useful in that they can provide tens of thousands of years of data, which can be accurately dated by counting varves.

Glenn Morton, citing Richard Flint's work:
A rhythmite deposited in a lake near Interlaken in Switzerland consists of thin couplets each containing a light-colored layer rich in calcium carbonate and a dark layer rich in organic matter. Proof that the couplets are annual, and therefore varves, is established on organic evidence, first recognized by varves, is established on organic evidence, first recognized by Heer(1865). The sediment contains pollen grains, whose number per unit volume of sediment varies cyclically being greatest in the upper parts of the dark layers. The pollen grains of various the upper parts of the dark layers. The pollen grains of various genera are stratified systematically according to the season of blooming. Finally, diatoms are twice as abundant in the light-colored layers as in the dark. From this evidence it is concluded that the light layers represent summer seasons and the dark ones fall, winter and spring. Counts of the layers indicate a record that is valid through at least the last 7,000 years B. P. Richard Foster Flint, Glacial and Quaternary Geology, New York: John Wiley and Sons, Inc., 1971, p. 400.

Another careful analysis of varves extends the data much farther:

Lake Suigetsu is located near the coast of the Sea of Japan (35°35'N, 135°53'E). The lake is 10 km around the perimeter and covers 4.3 km2. It is a typical kettle-type lake, nearly flat at the center, Ca. 34 m deep. A 75-m-long continuous core (Lab code = SG) and four short piston cores (Lab codes = 501, -2, -3 and -4) were taken from the center of the lake before 1993 (Kitagawa et al. 1995).

The sediments are characterized by dark-colored clay with white layers due to spring season diatom growth. The seasonal changes in the depositions are preserved in the clay as thin, sub-millimeter scale laminations or "varves". Based on observation of varve thickness change, we expect that the annually laminated sediment records the paleoenvironmental changes during the past 100 ka. This sequence of annually laminated sediments not only forms a unique continuous paleoenvironmental record after the last interglacial but also permits us to reconstruct a complete 14C calibration extending back to at least 40 ka BP, and probably even more by means of combined isotope enrichment and AMS 14C dating (Kitagawa and van der Plicht 1997). We have performed AMS 14C measurements on >250 terrestrial macrofossil samples of the annual laminated sediments from Lake Suigetsu. Here, we report varve and 14C chronologies of these sediments. The combined varve and 14C chronologies back to 40,000 BP are used to reconstruct a 14C calibration curve for the total range of the 14C dating method.
HIROYUKI KITAGAWAI and JOHANNES VAN DER PLICHT2
Proceedings of the 16th International 14C Conference, edited by W. G. Mook and J. van der Plicht
RADIOCARBON, Vol. 40, No. 1, 1998, P. 505-515

 

[zeke]

No assumptions there.

But you are assuming are you not? Do you offer proof that all varve-like deposits represent annual processes? I think not. In your arm-chair version of geology can turbidity currents be mistaken for varves or have you scientifically ruled that out? Remember, assumptions are not 'proof' of anything.

 

[lordkalvan]

I would like to exam your evidence from science (if you have any) that proves the uniformitarian assumption that millions of varves represent millions of years. Do you have such evidence?

Surely it would be sufficient to demonstrate that varves are what the evidence shows them to be? Any varve-sequence greater than some 4,500 years in extent is sufficient to invalidate YEC chronologies and ideas about Earth's history. Would you like to examine that evidence by discussing Mia Tiljander's paper, which looks at varves recounting a history of some 9,000 years of sedimentation and climate variation? If you want to look at varve sequences that demonstrate more extensive histories we can then look at other evidence from, say, Lake Suigetsu, Lake Baikal and the Green River formation.

 

[zeke]

Surely it would be sufficient to demonstrate that varves are what the evidence shows them to be?

And again I ask you - can you present evidence from science that proves the uniformitarian assumption that millions of varves represent millions of years. Do you have such evidence?

 

[Barbarian]

But you are assuming are you not?

Nope. Citing evidence.

Do you offer proof that all varve-like deposits represent annual processes?

Yep. Pollen counts, directly observed formation of varves, and of course, the correlation of varve data with dendrochronology and other data.

In your arm-chair version of geology can turbidity currents be mistaken for varves

Nope. Pollen distribution in the light and dark phases rules that out.

or have you scientifically ruled that out? Remember, assumptions are not 'proof' of anything.

Surprise.

 

[lordkalvan]

But you are assuming are you not?

Nope, making reasoned conclusions from available evidence.

Do you offer proof that all varve-like deposits represent annual processes?

There are no varve-like deposits that are varves. There are plenty of laminae that are not varves that are laid down under different depositional conditions. Geologists can distinguish amongst these and spend a lot of time and effort making sure that what they think are varves are, indeed, varves.

I think not.

On what basis do you 'think not'?

In your arm-chair version of geology can turbidity currents be mistaken for varves or have you scientifically ruled that out? Remember, assumptions are not 'proof' of anything.

So is your version of geology practical and derived from actual fieldwork, or do you have a more home-based view? The straightforward answer to your question is no, they can't. If your point is that geologists can make mistakes from time to time, then that is certainly the case, but in order to invalidate varve chronologies you have to show that hundreds of geologists have been consistently mistaken in their analyses for nearly a century of research. Good luck with that.

 

[lordkalvan]

And again I ask you - can you present evidence from science that proves the uniformitarian assumption that millions of varves represent millions of years. Do you have such evidence?

You seem very eager to avoid discussing Mia Tiljander's work as I offered to. Why is that? Once we have discussed the soundness of her conclusions, it is reasonable then to progress to looking at other varve formations that extend our understanding further into the past. Would you like to begin this process?

 

[zeke]

You seem very eager to avoid discussing Mia Tiljander's work as I offered to. Why is that? Once we have discussed the soundness of her conclusions, it is reasonable then to progress to looking at other varve formations that extend our understanding further into the past. Would you like to begin this process?

Why don't you first present evidence from science that proves the uniformitarian assumption that millions of varves represent millions of years. Or just admit the truth - you have no such evidence?

 

[zeke]

There are no varve-like deposits that are varves.

You didn't answer the question. Do you offer proof that all varve-like deposits represent annual processes? You do understand the question or do you need help? Are you stumped or can you provide evidence from science that proves the uniformitarian assumption that millions of varves represent millions of years? Take your time.

 

[zeke]

Pollen distribution in the light and dark phases rules that out.

Lol - how exactly do "light and dark phases" prove turbidity currents cannot be mistaken for varves? Please be specific - you may be in over your head.