Re: Last Word (from me) on the Crackpot Theory, I Think...
Paul bristolia at yahoo.comTue Nov 1 12:05:13 EST 2005
Sterling Webb wrote:
" The clustering I mentioned came from a
complete list of dated carcases. Most dates
were single and isolated times, but there
were several dates clustered around the
two time periods Firestone found (elsewhere)
anomalies for. It was a very weak association
and I probably shouldn't have even suggested it
supported even vaguely the isotopic timetable.
And it was the one from the "talkorigins"
website you recommended, Paul."
The fundamental problem. as I pointed out in my last post in
detail, is not that the clustering is "weak". This problem is that
given few number of dates available, it is impossible to know
at this time if it exists at all. A few data points selected from
a larger population of data points can be and usually is quite
misleading. In case of the 30,000 to 35,000 BP period is
absolutely no clustering of dates in that time period.
Sterling Webb wrote:
"When I referred to the megafauna extinction
at 13,000 to 11,000 years ago, I was referring
SOLELY to North America and said so. I
specifically mentioned that the extinctions took
place at other times on other continents. What
Paul called this "old misstatement of the facts,
which has been endlessly recycled on various
catastrophist web sites despite having been
long known to be quite false" was mostly taken
from the web site of the American Museum of
Natural History in New York, New York..."
One problem is that just because something is posted on a web
page does not make it true. Unfortunately, even the web pages
of reputable museums are often **not** peer-reviewed and
sometimes prepared by publicists and other non-scientists, who
repeat what they learned years ago in school and not what is
now known about the subject. As a result, old, outdated
material is recycled with the best of intentions, regardless of
whether the information in it is still supported by the current
research.
Apparently, whoever wrote the Natural Museum of Natural
History web page, like the catastrophists and other people, who
also repeat this claim their web pages, mindlessly repeated
Paul S. Martin and H. E. Wright in their 1967 book "Pleistocene
Extinctions " when they stated:
"A sudden wave of large animal extinction,
involving at least 200 genera, most of them
lost without phyletie replacement,
characterized the late Pleistocene."
Unfortunately for whoever prepared the Museum of Natural
History web pages, they, like various catastrophists, failed to
research what they were writing. Had the done this, they would
have found that in the 38 years since book "Pleistocene
Extinctions " was published, research has conclusively proved
that Paul S. Martin and H. E. Wright were totally wrong about
there being a single and sudden wave of extinctions. They
occurred at different times in different places over a period
of tens of thousands of years as demonstrated by the articles,
which I cited in my previous papers.
The disproved nature of Martin and Wright's "200 genera"
statement is important because, the fact there was **not** a
single wave of extinction greatly contradicts the idea of using
a supernova to explain such extinctions. (Also, it reflects badly
one a person's scholarship to use antiquated and long discarded
and disproved ideas to support a person's hypothesis.) The
multiple waves of extinction, which occurred on different
continents at different times over a period of tens of thousands
of years is **not** the pattern of extinction that would be
expected from a supernova, which would have caused a single
synchronous extinctions event of global extent. An extinction
event associated with a supernova would have more resembled
the Cretaceous-Tertiary boundary because of the amount of
irradiation proposed by Firestone and his colleagues based on
his chert data and many other nasty aftereffects of a supernova.
It is impressive that 15 genera of mostly megafauna became
extinct at the end of the Pleistocene in North America.
However, this is far too localized to have been caused by a
supernova. Also, as noted in papers discussed in my previous
post, i,e, Stafford et al (2005) paper in the same conference,
which found that it actually consisted of two waves of
extinction, which is inconsistent with a supernova or any
other instantaneous event. A supernova or similar cosmic
event also cannot explain why horses in Alaska were being
subject increasing environmental stress before they became
extinct in Alaska before elsewhere and why remnant
populations of mammoths survived on St Paul island a
couple of thousand years past 10,000 BP.
Sterling wrote:
"Here is the problem with my attempting
to deal with the data (the isotopic anomalies).
People seem to consider me instead a
supporter of various theories, whacky or
not, Firestone's or any other's, about
extinctions. I have no brief for these
theories. I am interested only in what
exterior astronomical events created
these isotopic anomalies. They require
an explanation."
There is nothing wrong with this. However, a person needs to
carefully vet what they find on web pages to separate fact from
either fiction; antiquated and disproved conclusions; and
misstated and mangled facts. Basing your conclusions on ideas,
i.e. Martin and Wright's "200 genera" statement, which have
been disproved is not the way to this.
...text deleted...
Sterling wrote:
"Marco mentions the vagaries of radiocarbon
dating and so forth. It's obvious nobody is
reading the reference I gave for Firestone's
earlier paper on them:
<http://www.centerfirstamericans.com/mt.html?a=36 >
It derives, among other things, from
trying to calibrate those vagaries.
As a geochronologist, he was (apparently)
called in to examine material from a group of
paleoindian sites that, in varying degrees,
yielded anomalous dates.
Below a strata well-known to date geologically
to 10,000 BP (before present) are artifacts with
thermoluminescent dates of 12,400 BP but with
radiocarbon dates that are almost recent, 2880 BP.
There are a number of these sites, including
one where there is an area with an archaic
cultural items whose radiocarbon date is 160
years old!"
Sterling wrote:
One signifcant problem here is that thermoluminescent dating
presumes a steady level of radiation damage over time by the
decay of radioactive elements trapped in either quartz or
feldspar comprising the sand. Irradiation significant enough
to have altered the isotopic composition of uranium in chert
would have also caused extensive radiation damage to the
quartz and feldspar in the sand surrounding. Therefore, had
what Firestone and his colleagues claimed to have occurred,
actually happened, any thermoluminescent dates from the
effected site should have also been altered to the point of
providing apparent dates considerably older than the
associated Paleo-Indian artifacts. The fact, that the
thermoluminescent dates are only slightly older, which is
common due to incomplete bleaching of the sand, than age
of the culture affiliated with the Paleo-Indian artifacts, strongly
refutes the idea that these sites were irradiated at all. Had
these sites been irradiated as much as proposed by Firestone,
then the ages given by the thermoluminescent dates would
have given apparent dates significantly older than the
artifacts actually are,which was not the case.
Sterling wrote:
"This indicates an large excess of
radiocarbon, which is normally formed
in the upper atmosphere by the solar
wind (protons) and cosmic rays (also
protons) at a relatively constant rate,
but in fact is produced in variable
qualtities. But these excesses are far
beyond mere variation, much larger."
The fundamental problem here is that Firestone and his
colleagues, although they cite texts on geomorphology and
pedology, failed to understand that although Paleo-Indian
archaeological deposits may occur at depth in Wisconsinan
deposits that predate Holocene sediment buildup that it does
not mean that these deposits are undisturbed by pedogenesis,
weathering, and other processes. In case of the Paleo-Indian
sites, which they mentioned, they have greatly misjudged, as
did the archaeologists, who originally dug the sites, by greatly
underestimating the degree to which these sites have been
modified by pedogenesis, including bioturbation. The fact
of matter is that it is quite possible, in fact probable, that
the charcoal and other organic matter, which gave the
anomalous dates was mixed into the Paleo-Indian levels by
bioturbation. The claim that the archaeological sites, form
which he cited C14 data have **not** been altered in any
way by pedogenesis, specifically bioturbation, is simply
false. It is impossible for them to claim that the C14 dated
material could not have been introduced by bioturbation.
Sterling Webb wrote:
"Firestone finds other isotopic anomalies.
The soil itself is radioactively enhanced.
The uranium content of the flint implements
is very abnormal. This whole area of the
upper Midwest US has been, more than
once, irradiated on a massive scale. Go
to the link; read the details.
Everything indicates a massive radiation
exposure. This is not a minor occurrence.
The dose is "comparable to being irradiated
in a 5-megawatt reactor more than 100
seconds," in other words, instantly lethal."
This paragraph states a fundamental problem with the supernova
idea. Such an event would have obliterated entire ecosystems in
an area, if not the entire world. In case of a supernova, the
irradiation would have lasted more than 100 seconds. The initial
burst of gamma rays would have destroyed Earth's ozone layer
by creating massive amounts of nitrous oxide and other
chemicals. As a result, the sky would have turned brown with
the entire Earth shrouded in a brown toxic smog and ultraviolet
radiation, 50 times above normal, powerful enough to killed
exposed life, would have bathed the Earth. Even if the initial
burst of gamma rays was by some mysterious process localized,
such a supernova would cause a global disruption of ecosystems.
More than just mammoths and mastodons would have become
extinct. Not just the Midwest would have been effected.
Just in the Midwest, there are more than a couple dozen cores
from lakes and ponds, which have yielded pollen records
recording environmental changes back into the last glacial and,
in a couple case, the last interglacial. In none of these records is
there indication of the type of catastrophic ecological
disruptions, which such an event would have caused, for the
past 14,000 years, and in a couple of cases, more than the
past 100,000 years.
Although Firestone and his colleagues talk about random
anomalies in Be and other elements as evidence of their having
been a supernova, this proposal makes absolutely no sense in
the fact that the buildup of cosmogenic nuclides, i.e. Be10,
Al26, and Cl36, within the upper one meter of the land's
surface has been and is being used to date various types of
landforms, i.e. glacial moraines, river terraces, and alluvial
fans, which are hundreds of thousands of years old. The fact
that cosmogenic dating works as well as it does, is strong
evidence that the steady accumulation of these isotopes in
the ground's surface, including dates form the Midwest, have
not been disturbed by being irradiated by a supernova event.
For details, look at "Cosmogenic Exposure Dating and the Age
of the Earth" at
http://www.geocities.com/earthhistory/tcn.htm
The fact that Cosmogenic Exposure Dating works as well as
it does indicates to me that the isolated and quite random
isotope anomalies, from which Firestone and his colleagues
base their ideas have a far different cause than they have so
far proposed.
The reason nobody really pays an serious attention to Firestone
is that he has done an extremely poor job of understanding the
consequences of what he proposed and of explaining why none
of the obvious consequences of his hypothesis can be found in
the enormous amount of paleoenvironmental data that has been
published in the scientific literature.
Best Regards,
Paul
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