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Author Topic:   Which animals would populate the earth if the ark was real?
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 885 of 991 (709218)
10-22-2013 4:34 PM
Reply to: Message 884 by NoNukes
10-22-2013 2:20 PM


Re: Uniformity assumptions...
Even worse for our deluded pal, the Mississippi River is around 10,000 years old, and at most parts of it could be two million years old. The Mesozoic ended around 65 million years ago. So speaking of the Mississippi River during the Mesozoic is ipso facto meaningless.

This message is a reply to:
 Message 884 by NoNukes, posted 10-22-2013 2:20 PM NoNukes has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 887 of 991 (709225)
10-22-2013 6:54 PM
Reply to: Message 886 by NoNukes
10-22-2013 5:55 PM


Re: Uniformity assumptions...
His "mechanism" would disturb secular equilibrium in the U and Th decay chains, and we would see that today. Of course our pal has never heard of secular equilibrium.

This message is a reply to:
 Message 886 by NoNukes, posted 10-22-2013 5:55 PM NoNukes has seen this message but not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 888 of 991 (709229)
10-22-2013 8:39 PM
Reply to: Message 886 by NoNukes
10-22-2013 5:55 PM


Re: Uniformity assumptions...
Oh, and he /she thinks rates are currently slowed by the neutrons and were on the order of 10^5 faster for a few thousand years until around 300 CE. I haven't found any reference for this slowing by neutron Flux and he's provided none. If it exists I bet it doesn't happen under terrestrial conditions.

This message is a reply to:
 Message 886 by NoNukes, posted 10-22-2013 5:55 PM NoNukes has not replied

Replies to this message:
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JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 893 of 991 (709266)
10-23-2013 11:47 AM
Reply to: Message 869 by mindspawn
10-22-2013 6:52 AM


Re: Uniformity assumptions...
Sedimentation would have to be about 50 000 times slower during the Mesozoic to explain fossilisation along the Mississippi.
The Mississipi river is 10,000 years old. Maybe parts of it were formed between 10,000 and 2,000,000 years ago. The Mesozoic ended about 66 million years ago. Even it you try to condense the time scale, the Mississippi river did not exist during the Mesozoic.
I suppose your condensed time scale has the Mississippi river forming much more recently than 10,000 years ago, since you've got the Mesozoic ending much less than about 4,000 years ago. You've looked up the sediment transport rate. What is the total amount of sediment transported by the Mississippi river in your time frame, and how does that compare with the mass of the Mississippi delta?

This message is a reply to:
 Message 869 by mindspawn, posted 10-22-2013 6:52 AM mindspawn has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 902 of 991 (709287)
10-24-2013 8:11 AM
Reply to: Message 899 by mindspawn
10-24-2013 7:17 AM


Re: Uniformity assumptions...
Not Found
"Neutron capture can occur when a neutron approaches a nucleus close enough for nuclear forces to be effective. The neutron is captured and forms a heavier isotope of the capturing element."
In stars. The neutron flux, temperature, and pressure on Earth at any time during its existence are nowhere near enough to produce your alleged effect. Elements and isotopes heavier than iron are produced only in supernovae, not even in ordinary novae. No way have they ever been produced on Earth. {ABE: under terrestial conditions. Maybe appropriate conditions have been produced in a lab, but I doubt it.}
And even after that destroys your argument, you need to have relevant radioactive isotopes produced at a rate that exactly matches their decay rate minus a little bit in order for the various dating methods to be as consilient as we see.
From Earth's Magnetic Field Strength - Past 800,000 Years:
We see that the strength of the Earth's magnetic field has varied considerably over the last 50,000 years. In your scenario that would have affected the 14C dates in Suigetsu's varves in a highly nonlinear fashion. But the correlation between varve count and 14C dates is pretty darned linear.
That's all the occurs to me off the top of my head. Bet others can come up with more gaping holes.
All in all,
Edited by JonF, : No reason given.
Edited by JonF, : No reason given.

This message is a reply to:
 Message 899 by mindspawn, posted 10-24-2013 7:17 AM mindspawn has replied

Replies to this message:
 Message 909 by NoNukes, posted 10-24-2013 5:28 PM JonF has replied
 Message 915 by mindspawn, posted 10-25-2013 4:11 AM JonF has replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 903 of 991 (709289)
10-24-2013 8:41 AM
Reply to: Message 901 by NoNukes
10-24-2013 7:54 AM


Re: This so bad it is disrespectful.
Uranium 235 does not transmute to higher elements when bombarded by neutrons. It undergoes fission roughly into nucleii half roughly original size and releasing lots of energy. This would be quite detectable. The neutron flux would not make it decay or transmute to new elements.
Mindie's fantasy is so wacked out it's really hard to wrap your mind around it. But I bet that if it happened it would really blow secular equilibrium away with 235U fissioning and the decay products forming new elements. But we see lots of rock samples in secular equilibrium.

This message is a reply to:
 Message 901 by NoNukes, posted 10-24-2013 7:54 AM NoNukes has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 906 of 991 (709312)
10-24-2013 2:07 PM


One more thought: perhaps neutron capture in a sufficiently high flux could "reconstitute" some radioactive parent elements. I'm not a nuclear physicist. But how would neutron capture "reconstitute" parents that decay by alpha particle (a helium nucleus, two neutrons and two protons) emission? Such as 87Rb and several isotopes in the U and Th decay series.
And what of the electron capture decay of 40K?
It's all so incredibly laughable.

Replies to this message:
 Message 910 by NoNukes, posted 10-24-2013 5:55 PM JonF has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 918 of 991 (709340)
10-25-2013 8:12 AM
Reply to: Message 909 by NoNukes
10-24-2013 5:28 PM


Re: Uniformity assumptions...
In stars. The neutron flux, temperature, and pressure on Earth at any time during its existence are nowhere near enough to produce your alleged effect.
Actually, this part of the proposal does work in terrestial conditions. Neutrons, having no charge, easily find their way into the nucleus of atoms.
Hum. Makes sense. Yet I'm sure that elements above iron are only created in supernovae. Maybe neutron capture is not important in making new elements?

This message is a reply to:
 Message 909 by NoNukes, posted 10-24-2013 5:28 PM NoNukes has replied

Replies to this message:
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JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 921 of 991 (709343)
10-25-2013 8:36 AM
Reply to: Message 915 by mindspawn
10-25-2013 4:11 AM


Re: Uniformity assumptions...
And even after that destroys your argument, you need to have relevant radioactive isotopes produced at a rate that exactly matches their decay rate minus a little bit in order for the various dating methods to be as consilient as we see.
Is there any reason why the effect would not be proportionate?
Wrong question. The burden of proof is yours. I see no reason why it should be proportionate. It's your job to provide evidence that it would be proportionate. That's required as one of the many questions you must answer to establish your fantasy as a viable hypothesis.
A lot of consilience in radiometric dating is due to calibrating against existing methods.
Ar-Ar dating is calibrated against existing methods. Other methods are not. (well, occasionaly they are,but it's rare; see below). You need to explain all the consilience.
I have often searched for evidence of how the rates were established in the first place, correct me if I'm wrong, but it seems they measure the changing ratio of parent to daughter over time, by literally separating the rock in a mass spectrometer.
It's not all that difficult to find. Begemann et al have a good summary in the introduction of Call for an improved set of decay constants for geochronological use. It's not open access, but I have a copy:
quote:
Accurate radioisotopic age determinations require accurate decay constants of the respective parent nuclides. Ideally, the uncertainty on the decay constants should be negligible compared to, or at least be commensurate with, the analytical uncertainties of the mass spectrometric measurements entering the calculations. Clearly, this is not the case at present. The stunning improvements in the performance of mass spectrometers during the past three decades, starting with the seminal paper by Wasserburg et al. (1969), have not been accompanied by any comparable improvement in the accuracy of the decay constants.The uncertainties associated with direct half-life determinations are, in most cases, still at the percent level at best. The recognition of an urgent need to improve the situation is not new (cf., e.g., Renne et al., 1998; Min et al., 2000a); it has presumably been mentioned, at one time or another, by every group active in geo- or cosmochronology. The present contribution is intended to be a critical guide to the existing experimental approaches. Except in a few cases, we do not evaluate the individual reports on decay constants, and we also do not make any recommendations as to which values should be considered “correct” and be used by the dating community at large. This must, in our opinion, be left for existing commissions to decide, following the precedent of Steiger and Jager (1977). Three approaches have so far been followed to determine the decay constants of long-lived radioactive nuclides.
1. Direct counting. In this technique, alpha, beta or gamma activity is counted, and divided by the total number of radioactive atoms. Among the difficulties of this approach are the self-shielding of finite-thickness solid samples, the low specific activities, imprecise knowledge of the isotopic composition of the parent element, the detection of verylow- energy decays, and problems with detector efficiencies and geometry factors. Judged from the fact that many of the counting experiments have yielded results that are not compatible with one another within the stated uncertainties, it would appear that not all the difficulties are always fully realized so that many of the given uncertainties are unrealistically small, and that many experiments are plagued by unrecognized systematic errors. As the nature of these errors is obscure, it is not straightforward to decide which of the, often mutually exclusive, results of such counting experiments is closest to the true value. Furthermore, the presence of systematic biases makes any averaging dangerous. Weighted averaging using weight factors based on listed uncertainties is doubly dubious. It is well possible that reliable results of careful workers, listing realistic uncertainties, will not be given the weights they deserve-this aside from the question whether it makes sense to average numbers that by far do not agree within the stated uncertainties.
2. Ingrowth. This technique relies on measuring the decay products of a well-known amount of a radioactive nuclide accumulated over a well-defined period of time. Where feasible, this is the most straightforward technique. Ingrowth overcomes the problems encountered with measuring large fractions of low-energy b-particles, as in the case of 87Rb and 187Re. It also comprises the products of radiation- less decays (which otherwise cannot be measured at all) like the bound-beta decay branch of 187Re and the possible contribution to the decay of 40K by electron capture directly into the ground state of 40Ar. Among the drawbacks of this approach is that the method is not instantaneous.The experiment must be started long before the first results can be obtained because long periods of time (typically decades) are required for sufficiently large amounts of the decay products to accumulate. “Ingrowth”-experiments further require an accurate determination of the ratio of two chemical elements (parent/daughter) as well as an accurate determination of the isotopic composition of parent and daughter element at the start of the accumulation (see below). Moreover, because of the hold-up in the chain of intermediaries, for uranium and thorium measuring the ingrowth of the stable decay products in the laboratory does not work at all.
3. Geological comparison. This approach entails multichronometric dating of a rock and cross-calibration of different radioisotopic age systems by adjusting the decay constant of one system so as to force agreement with the age obtained via another dating system. In essence, because the half-life of 238U is the most accurately known of all relevant radionuclides, this amounts to expressing ages in units of the half-life of 238U.
This procedure is less than ideal, however.The different radioisotopic dating systems were developed, and as a rule are being utilized, because different parent/daughter element pairs are affected in different ways by different geological processes. Thus, employing a variety of element pairs often allows to distinguish chemical, thermal, mechanical, or other processes capable of fractionating or homogenizing the chemical signature of its minerals during a rock’s history. It is the sequence of such events that one wants to learn about.This, in turn, implies that there is the practical problem of selecting a sample where the initial event starting the radioisotopic clock was so short and simple as to be truly “point-like” in time, and whose subsequent perturbations were totally nonexistent. As illustrated by the case of early comparisons between Rb-Sr and K-Ar ages, or K-Ar and U-Pb ages, on non-retentive materials like micas, feldspars, and uraninites in plutonic rocks, simple concepts about “ideal” samples that were considered valid a quarter of a century ago have not withstood the test of time. Our present perception of isotopic closure has been changed as a result of improved understanding of mineralogy and isotope systematics; consequently, now the definition of a “point-like event” is more restrictive than that implicitly assumed by the studies that influenced Steiger and Jager (1977). The obvious requirements are that the two isotopic systems being compared are exactly coherent due to simple thermal, chemical, and mechanical histories. In addition to selecting a sample which was rapidly quenched from a magmatic stage, it is of vital importance to ascertain that the sample escaped any retrogressive change of mineralogy and especially any exchange with fluids, and was spared any later disturbance, chemical and/or thermal. This can be investigated by detailed microchemistry of major and trace elements. Vagaries and problems potentially encountered with the “standard” Pb-Pb and U-Pb ages used for this kind of calibration have most recently been discussed by Tera and Carlson (1999).
We see that the strength of the Earth's magnetic field has varied considerably over the last 50,000 years. In your scenario that would have affected the 14C dates in Suigetsu's varves in a highly nonlinear fashion. But the correlation between varve count and 14C dates is pretty darned linear.
Its only linear because they already adjust their dates according to the magnetic field effect on carbon dating. The effect is attributed to the changing production of atmospheric carbon during fluctuations in the magnetic field.
{ABE: Mindie, see Message 933 before responding to the following section}
Wrong again, as usual. The relationship between raw unadjusted carbon dates and varve counts is within 10% or less of perfect linearity. From RADIOCARBON DATING:
The line at 45 degrees is perfect linear relationship. The X-coordinate of the purple crosses is the varve count age, the Y coordinate of the purple crosses is the raw 14C age of the varve (that's why they specified "(14C)" in the axis label, that mens "radiocarbon unadjusted"). If those cross's 14C ages were adjusted by the standard calibration method they would lie directly on the 45 degree line. But once Suigetsu varve counts have been used to construct the calibration curve, you can't adjust their 14C ages by using the calibration curve; that would be circular reasoning. Real scientists aren't that stupid.
{ABE}And note the near-perfect consilience between tree rings and varve counts and unadjusted 14C ages.
{ABE again}Note the total lack of consilience between the raw 14C ages and the magnetic field history I posted earlier.
Edited by JonF, : No reason given.
Edited by JonF, : Clarify Y-axis label
Edited by JonF, : No reason given.
Edited by JonF, : Add note to Mindie.

This message is a reply to:
 Message 915 by mindspawn, posted 10-25-2013 4:11 AM mindspawn has not replied

Replies to this message:
 Message 933 by JonF, posted 10-25-2013 12:14 PM JonF has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 923 of 991 (709345)
10-25-2013 8:51 AM
Reply to: Message 917 by NoNukes
10-25-2013 7:48 AM


Re: This so bad it is disrespectful.
Not possible for the flux to be slight. According to you, the neutron flux intervenes by converting atoms to higher isotopes. Thus the flux must affect enough atoms to explain the entire difference between the high decay rates you say used to exist and the current rates.
It's unclear whether mindie's speaking of isotopic or elemental transmutation, but I think he means transmuting daughter elements back to parent elements.
In fact when we measure the rate of decay of U235 or U238, we take a sample in which the other isotopes have been removed.
Another excerpt from Begemann et al seems appropriate:
quote:
The decay of 238U and 235U to 206Pb and 207Pb, respectively, forms the basis for one of the oldest methods of geochronology. While the earliest studies focused on uraninite (an uncommon mineral in igneous rocks), there has been intensive and continuous effort over the past three decades in U-Pb dating of more-commonly occurring trace minerals. Zircon in particular has been the focus of thousands of geochronological studies, because of its ubiquity in felsic igneous rocks and its extreme resistance to isotopic resetting.
No decay constant of any radionuclide used for geochronology has been (or, arguably, can be) more-precisely measured than those of 238U and 235U”a consequence of the mode of decay (alpha), favorably short half-lives, and the availability of large quantities of isotopically pure parent nuclides {bombs and reactors, ya know - JonF}. The most recent measurements by Jaffey et al. (1971) (Figs. 1, 2) quote precisions (recalculated to 95%-confidence limits) of 0.11% for 238U and 0.14% for 235U, with the somewhat cryptic statement that “systematic errors, if present, will no more than double the quoted errors.”
{emphasis added}

This message is a reply to:
 Message 917 by NoNukes, posted 10-25-2013 7:48 AM NoNukes has replied

Replies to this message:
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JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 924 of 991 (709346)
10-25-2013 8:56 AM
Reply to: Message 919 by NoNukes
10-25-2013 8:30 AM


Re: Uniformity assumptions...
Also U-Th dating depends on an equilibrium amount of daughter products
Perhaps overly pedantic, but U-Th dating depends on the lack of an equilibrium amount of daughter products. E.g. corals. Uranium is pretty soluble in seawater, Thorium is not. When U decays to Th the Th settles out and is incorporated into coral. But it's not in secular equilibrium with its daughter products and won't be for may thousands of years. We take advantage of that fact.

This message is a reply to:
 Message 919 by NoNukes, posted 10-25-2013 8:30 AM NoNukes has replied

Replies to this message:
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JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 929 of 991 (709368)
10-25-2013 11:26 AM


French-fried people everywhere!
Cross-posted since Mindie seems to have been scared away from the genetic thread:
I need links, I need calculations. I don't care about the source of information, if the information makes sense then I respect it.
Well, you've got links and calculations. Which you obviously don't respect and are incapable of addressing. We ride into the sunset, leaving the charnel house that mindspawn's scenario would make of Earth as the fantasy that it is.
Message 157 and Heat and radiation destroy claims of accelerated nuclear decay.
And, mindspawn, your problem is much worse than I calculated in the linked message. Most proponents of accelerated nuclear decay have it happening during the fludde so Noah et. al. are somewhat shielded by water. That's not your scenario. In your scenario life is exposed to all the background radiation from the Earth itself and other living things and construction materials an whatnot. This "terrestrial background" exposure varies widely, from 2 nGy/hr (Ireland) to 1,300 nGy/hr (China) (from United Nations Scientific Committee on the Effects of Atomic Radiation, UNSCEAR 2008 Report to the General Assembly, with scientific annexes Annex B, table 6 on the 109th page.) That translates to 17.5 to 11,388 μGy/year. The conversion to Sieverts requires a weighting factor that depends on the type of radiation and ranges from 1 to 20 (see Wikipedia). So let's be as kind as possible and use 1 as the weighting factor. Therefore, 17.5 to 11,388 μSv/year.
In the linked message I calculated that mindie's scenario resulted in self-irradiation doses of about 10 Sv/year when radioactive decay is sped up by a factor of 100,000 relative to today. To that we must add the terrestrial contribution above; sped up by a factor of 100,000 that's 1.75 to 1,139 Sv/year. Those poor Chinese don't stand a chance, accumulating a 90% lethal dose every 6/(100 + 1139) = 0.0048 year = 1.8 days.
Mindspawn, this refutes your fantasy. Obviously you have no refutation. Your scenario would kill all life on Earth (except perhaps for cockroaches and some exteremophile bacteria) many, many times over. Game, set, match.

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 930 of 991 (709369)
10-25-2013 11:33 AM
Reply to: Message 926 by PaulK
10-25-2013 9:21 AM


Re: This so bad it is disrespectful.
Not only would there have been a neutron flux in the past, but the neutron flux in the present will still be affecting samples brought in for dating.
He thinks that the present-day neutron flux is much lower than in the past.

This message is a reply to:
 Message 926 by PaulK, posted 10-25-2013 9:21 AM PaulK has replied

Replies to this message:
 Message 931 by PaulK, posted 10-25-2013 11:47 AM JonF has replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 933 of 991 (709377)
10-25-2013 12:14 PM
Reply to: Message 921 by JonF
10-25-2013 8:36 AM


Re: Uniformity assumptions...
Just to make it even clearer, let's overlay the magnetic field changes for the last 50,000 years over the 14C calibration curve:
The relationship between varve count and 14C age is nearly 1:1. But over the last 40,000 years the Earth's magnetic field has varied from about 20% higher than today to about 45% lower than today. Mindie's fantasy would have 14C decay rates varying wildly over that period. The correlation between varve count and raw 14C age would not be anywhere near what's observed unless the varve formation were also varying in step with the Earth's magnetic field.
So, mindspawn, in your scenario how does the Earth's magnetic field affect the rate of formation of varves in lake Suigetsu and elsewhere?

This message is a reply to:
 Message 921 by JonF, posted 10-25-2013 8:36 AM JonF has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 934 of 991 (709378)
10-25-2013 12:15 PM
Reply to: Message 931 by PaulK
10-25-2013 11:47 AM


Re: This so bad it is disrespectful.
No, he thinks that we have a higher neutron flux now, that "slows down decay" (which doesn't mean slowing down decay, just transmuting the decay products).
You're right, it's hard to keep track of this risible fantasy.

This message is a reply to:
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