[meteorite-list] Re: Last Word (from me) on the Crackpot Theory, I Think...

[Paul]

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 As a result, old, outdated 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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