Including Original "Paul H. Letters" Copyright © 1996-2025 Paul V. Heinrich / website © 1996-2025 Dirk Ross - All rights reserved.



Saturday, 18 October 2008

Reevaluation of the Tektites from Proposed Mahuika Impact (New Zealand)

Reevaluation of the Tektites from Proposed Mahuika Impact (New Zealand)

Friday, October 17, 2008 4:07 AM

A Reevaluation of the Tektites Associated with
the Proposed Mahuika Impact, Mohana Kumar, Earth
and Environmental Sciences Journalism, Columbia
University - Master's Thesis

links to PDF file of Master's Thesis

http://www.mohikumar.com/science.html


http://www.mohikumar.com/PDFs/Science_Thesis_with_Abstract.pdf


Masters Thesis Figures

http://www.mohikumar.com/PDFs/Figures_final.pdf


Yours,

Paul H.

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites

Friday, October 17, 2008 4:20 AM


Sterling K. Webb wrote:

>Are these "alleged tektites" that you refer to the
>ones found in Glenmora, Rapides Parish, that were
>reported on by King in 1970?
>http://adsabs.harvard.edu/abs/1970Metic...5Q.205K

>No abstract or paper available. I guess these
>tektites are not popular.

Yes, they are the ones that I referred to.

>Former (?) List member Ed Albin:
>http://www.lpi.usra.edu/meetings/LPSC99/pdf/1357.pdf

>"King [1968] described a bediasite find within the
>upper Eocene Wellborn Formation in Grimes County,
>Texas. This deposit has been traced eastward and
>correlates with the Yazoo Clay Formation in Louisiana,
>Mississippi, Alabama, and the Dry Branch Formation
>in Georgia. It is entirely possible that North American
>tektites may eventually be recovered from upper
>Eocene deposits between Georgia and Texas."
>
>But were King's tektites North American tektites in
>composition? Wetback Bediasites, as it were?

According to King (1970), their composition was
identical to certain Australites. They also were
dated by K/Ar dating to about the same age as
Australites. Therefore, they clearly are not North
American strewn field tektites. I expect that when
someone looks at the right outcrop, that tektites
of the North American strewn field will be found
in either Eocene strata of the right age or
redeposited in younger Pliocene or Pleistocene
gravels within Louisiana.

>In 1986, leading geochemist Cristian Koeberl
>said the King tektites from Louisiana were Australites:
>http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.ea.14.050186.001543?journalCode=earth

>I can't get to that paper, naturally.

Again, that is what King (1970) concluded from
composition and K/Ar dating. The tektite examined
by King (1970) was one of two specimens sent him
by an unnamed "Louisiana rancher" as possible
meteorites. The rancher said that he had found
it and two other similar specimens at a "local"
gravel pit in 1965.

>I can get to this paper by Koeberl (and so can
>everybody else on the List). It's his analysis
>of the Cuban "tektite" which proved to be a
>member of the North American strewnfield:
>http://adsabs.harvard.edu/full/1988Metic..23..161K

>but I can't pull a quote out as the paper's a page
>image, not text. The gist of Koeberl's remark is
>that the "Cuban" tektite is genuine, in distinction
>to King's tektites which were "allergedly" found in
>Louisiana, were then discovered to be Australites,
>and therefore could not have come from Louisiana.
>He said that they were a fraud, in other words.
>The tektites are tektites, but is the find a find
>in Louisiana?

The problem, as I have discovered doing archaeology,
is that people can be vary careless in keeping track,
what specimen was found and where it was and what
specimens were bought and where they were bought.
Unfortunately, some collectors of artifacts, fossils,
rocks, and tektite get their specimens mixed up and
lose track of what was found where. It was 5 years
between when the specimens were reported to have
been found and King's paper. One possibility is that
the collector lost track of where and how he
originally obtained the specimens. The question is
one of human carelessness that abounds among some
collectors.

There is the archaeological site in Hawaii where
hundreds of European Paleolithic artifacts were found
that shows how prehistoric materials have been
unintentionally moved about by humans in historic
times. How that happened is another story that is
quite instructional about how stuff gets misplaced
around the world by accident.

>but is the find a find in Louisiana?

That is the key question as King (1970) pointed out.

>What Koeberl was not aware of is that some years
>later Alan Hildebrandt (another geochemical
>authority) found some Australities in and around
>Tikal, the ancient Mayan city in Guatemala adjacent
>to the Yucatan. On the global scale, Louisiana and
>the Yucatan a mere tektite's throw apart, and both
>roughly antipodal to the Australasian strewnfield.

The Tikal tektites are unexplained. They consist
of 11 "nodules" found among obsidian tools in
various parts of the Tikal site, Guatemala. Unlike the
"Louisiana tektites", they were found during
archaeological excavations. Thus, it is known that
they are "in situ" at least within the region within
prehistoric times. It has been suggested that they
are tektites of the Muong Nong type. Also, they have
been Ar/Ar dated at 800,000+/-100,000 BP. Nothing
like them has been found at any other site or parts
of Central America. The Tikal tektites, like any
other tektite, continue to defy any attempt to
explain them.

A Couple Tikal tektite references:

Nagy, H. M.,2002, Tikal Report 27B: The Artifacts
of Tikal : Utilitarian Artifacts and Unworked
Material, University of Pennsylvania Museum
Publication, Philadelphia, Pennsylvania

Hildebrand, A. R., Moholy-Nagy, H., Koeberl, C.,
May, L., and others, 1994, Tektites found in the
ruins of the Maya city of Tikal, Guatemala. Lunar
and Planetary Science, vol. 77, pp. 213-219.

>If this is the case, then no amount of analysis of
>the "alleged" tektites is meaningful -- they are
>tektites!

I agree with King, Koeberl, and you that they are
tektites. The problem, which King (1970) also discusses,
is that it is uncertain whether these tektites came from
Louisiana or not.

>You would need instead need to investigate the
>circumstances of the find, the character and motives
>of the finder. This would seem to be a difficult goal
>to pursue definitively after a 38 year lapse.

That is what I have been doing off and on for a couple
of years. Having checked NASA, University of Houston,
king's daughter, and many other places, I found that
all of the field notes, laboratory notes, pictures,
maps, and specimen(s) related to King (1970) have
apparently been lost. Nobody, whom I have contacted,
know where these materials are. If anyone has any ideas
where these materials might be / can be found, please
drop me a note off-list with your ideas and suggestions.

>But if they are (both) Australites and were discovered
>in situ, that in itself is major news (or an inconvenience
>to be ignored, of course), like the Ivory Coast tektite
>(identified by analysis in 1982 by Shaw and Wasserberg)
>found off the coast of Australia in the sea bed. (Currents?
>Yeah, sure...)
>
>If Koerberl said the Louisiana tektites were real
>(and Australites), then they were tektites. No question.
>Better go find some more! Did anybody record the exact
>location of the find?

Apparently Dr. King did know as he and "three field
assistants" spent three days at the gravel pit looking
for more tektites and found none. While, talking with
people, I found that his daughter also accompanied
them to look for tektites. However, she did not
remember anything about the pit's location. Unfortunately,
any field or personal notes and maps about the exact
location of the gravel pits have apparently all been
either misplaced or discarded and utterly lost for any
practical purposes. Without this information, it is
impossible to find out who the "Louisiana rancher" was
and check to see if he might have either any more
specimens or information.

Another problem is that the gravel pits around Glenmora,
Louisiana have been largely reclaimed. Thus, even if we
knew exactly where the gravel pit was located, very
likely there would be nothing except grass and ponds to
look at.

If a person applies what is known about the local
geomorphology and Pleistocene sediments, there is a
specific “stratigraphic” horizon where a person can
expect to find them, if they exist. That is where I am
looking for them. Also, I have contacted knowledgeable
people have, after a fashion, have been looking over
the locations where any tektites might be found
around Glenmora on a regular basis for decades. What
they have and have not found does say something
about whether Louisiana tektites might exist. The
specific details of the above part of the story are
best told at another time and in another venue.

Yours,

Paul H.


Online Moldavite papers (including "Moldavites: a review")

Online Moldavite papers (including "Moldavites: a review")

Friday, October 17, 2008 11:28 PM

The Czech Geological Survey has a number
of papers published in the Bulletin of
the Czech Geological Survey. These papers
include some that discuss Moldavites.

The Czech Geological Survey web page is at:

http://www.geology.cz/extranet-eng


http://www.geology.cz/extranet-eng/search


The papers, which found are:

Trnka, M., and Houzar, S., 2002, Moldavites: a
review. Bulletin of the Czech Geological Survey.
Vol. 77, No. 4,pp. 283-302.

http://www.geology.cz/bulletin/contents/2002/vol77no4/04trnkafinal.pdf


Artemieva, N., E. Pierazzo, and Stoffler, D.,
2002, Numerical modeling of tektite origin in
oblique impacts: Implication to Ries-Moldavites
strewn field. Bulletin of the Czech Geological
Survey. vol. 77, no. 4, pp. 303-311.

http://www.geology.cz/bulletin/contents/2002/vol77no4/05artemievafinal.pdf


Sevcik, J., Z. Kvacek, and D. H. Mai, 2007, A
new mastixioid florula from tektite-bearing
deposits in South Bohemia, Czech Republic
(Middle Miocene, Vrábče Member). Bulletin
of Geosciences, Vol. 82, No. 4, 429-436,

http://www.geology.cz/bulletin/contents/2007/vol82no4/bullgeosci200704429.pdf


Kvacek, Z., and V. Teodoridis, 2007, Tertiary
macrofloras of the Bohemian Massif: a review
with correlations within Boreal and Central
Europe. Bulletin of Geosciences, Vol. 82,
No. 4, 383-408. Bulletin of Geosciences, Vol. 82, No. 4, 429-436,

http://www.geology.cz/bulletin/contents/2007/vol82no4/bullgeosci200704429.pdf


Yours,

Paul H.

Thursday, 16 October 2008

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites 1

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites

Wednesday, October 15, 2008 1:14 AM

Dear Friends,

Can anyone recommend a publication that provides a
comprehensive listing of Potassium-Argon (K/Ar) dates
that have been published for the North American and
Australasian tektites?

Also, what the authorative reference(s) work for
the bulk composition of tektites from each of these
strewn fields?

Any citations, which you can recommend would be
greatly appreciated.

Best Regards,

Paul H.

Tuesday, 14 October 2008

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites

Question About Potassium-Argon (K/Ar) dates for North American and Australasian Tektites

Paul bristolia at yahoo.com
Tue Oct 14 12:14:55 EDT 2008

Dear Friends,

Can anyone recommend a publication that provides a
comprehensive listing of Potassium-Argon (K/Ar) dates
that have been published for the North American and
Australasian tektites?

Also, what the authorative reference(s) work for
the bulk composition of tektites from each of these
strewn fields?

Any citations, which you can recommend would be
greatly appreciated.

Best Regards,

Paul H.

Saturday, 11 October 2008

Species Extinction By Asteroid A Rarity

Species Extinction By Asteroid A Rarity

Paul bristolia at yahoo.com
Sat Oct 11 23:16:51 EDT 2008

University of Southern California (2008, October 10). Species
Extinction By Asteroid A Rarity. ScienceDaily. Retrieved October
11, 2008, from

http://www.sciencedaily.com/releases/2008/10/081007102904.htm

Greene, S. E., D. J. Bottjer, F. A. Corsetti, and J. P. Zonneveld,
2008, Mass Extinction Déjà Vu: Seafloor Aragonite Fans near the
Triassic-Jurassic Boundary. Geological Society of America Abstracts
with Program. vol. 40, no. 6, p. 222.

http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_147579.htm

Martindale, R., 2008, Paleoecological Patterns of Reef Death and
Possible Causes for the Carbonate Collapse at the End-Triassic
Mass Extinction. Geological Society of America Abstracts with
Programs. vol. 40, no. 6, p. 279

http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_142398.htm

Heydrari, E. and others, 2008, Mantle Plumes and Phanerozoic
Biological Crises: Application to the Permian – Triassic Boundary
Mass Extinction. Geological Society of America Abstracts with
Programs. vol. 40, no. 6, p. 98.

http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_146945.htm

Richoz, S., and others, 2008, Repeated Photic Zone Euxinia after
the Triassic-Jurassic Mass-Extinction Event. Geological Society
of America Abstracts with Programs. vol. 40, no. 6, p. 505,

http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_146441.htm

A related news release is:

Extinction Theory Falls From Favor: The Great Dying 250 million
years ago happened slowly, according to USC geologists.
http://www.usc.edu/uscnews/stories/14432.html

Yours,

Paul H.

Asteroid blast may have thwarted life on Mars

Asteroid blast may have thwarted life on Mars

Paul bristolia at yahoo.com
Sat Oct 11 22:51:56 EDT 2008

Asteroid blast may have thwarted life on Mars
The Times, by Jonathan Leake, October 5, 2008

http://www.timesonline.co.uk/tol/news/uk/science/article4882708.ece

Yours,

Paul H.

Wednesday, 1 October 2008

Canada was a refuge during Permian-Triassic extinctions

Canada was a refuge during Permian-Triassic extinctions

Paul bristolia at yahoo.com
Wed Oct 1 09:43:52 EDT 2008

Canada a refuge in prehistoric holocaust by Randy Boswell
Canwest News Service, September 30, 2008
http://www.canada.com/topics/news/national/story.html?id=7e1d9583-f96b-4148-bec1-2cd1f66bad57

Canada's shores saved animals from devastating climate
change, EurekAlert, September 30, 2008
http://www.eurekalert.org/pub_releases/2008-09/uoc-css093008.php

Beatty, T. W., J-P Zonneveld, and C. M. Henderson, 2008,
Anomalously diverse Early Triassic ichnofossil assemblages
in northwest Pangea: A case for a shallow-marine habitable
zone. Geology. vol. 36, no. 10. pp. 771-774.

http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FG24952A.1&ct=1

Yours,

Paul H.

Monday, 15 September 2008

Koronis asteroid dust within Antarctic ice

Koronis asteroid dust within Antarctic ice

Paul bristolia at yahoo.com
Mon Sep 15 14:45:10 EDT 2008

Koronis asteroid dust within Antarctic ice

Genge, M. J., 2008, Koronis asteroid dust within Antarctic ice.
Geology. vol. 36, no. 9, pp. 687-690.

http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FG24493A.1

http://www.gsajournals.org/perlserv/?request=get-toc&issn=0091-7613

Ancient Koronis Space Rocks Reveal The Origin
Of Cosmic Dust, Submitted by News Staff on
2 September 2008 -

http://www.scientificblogging.com/news_releases/ancient_koronis_space_rocks_reveal_the_origin_of_cosmic_dust

Origin Of Cosmic Dust That Lands On Earth Discovered

http://www.sciencedaily.com/releases/2008/09/080902075227.htm

Yours,

Paul H.

Thursday, 11 September 2008

New Summary Paper on Permian Extinction (Downloadable for Free)

New Summary Paper on Permian Extinction (Downloadable for Free)

Paul bristolia at yahoo.com
Thu Sep 11 13:14:08 EDT 2008

Dear Friends,

"GSA Today"'s feature article for September is about the Permian
extinction. It is:

Bottjera, D. J., M. E. Claphama, M. L. Fraisera, and C. M.
Powersa, 2008, Understanding mechanisms for the end-Permian
mass extinction and the protracted Early Triassic aftermath
and recovery. vol. 18, no. 9, pp. 4-10.

It can be downloaded from:

http://www.gsajournals.org/archive/1052-5173/18/9/pdf/i1052-5173-18-9-4.pdf

and

http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FGSATG8A.1&ct=1

Yours,

Paul H.
Baton Rouge, LA

Monday, 1 September 2008

Pingualuit (One Last Post Before the Gustav Comes)

Pingualuit (One Last Post Before the Gustav Comes)

Paul bristolia at yahoo.com
Mon Sep 1 09:03:46 EDT 2008

Charles O'Dale wrote:

" http://www.flickr.com/photos/chuckexpeditions/2813874599/

I just returned from northern Quebec where I was exploring the
Pingualuit impact structure. This image gives you an appreciation
for the size of the crater!

Some URLs about Pingualuit Impact Crater.

St-Onge, G., H. Guyard, R. Pienitz, S. Hausmann, and others,
2007, Preliminary Chronostratigraphy of Pingualuit Impact
Crater Lake Sediments (Nunavik, Canada): a Possible Arctic
Terrestrial Record of Several Glacial/Interglacial Cycles.
Eos Trans. AGU. vol. 88, vol. 52. Fall Meet. Suppl.,
abstract no. U13B-1150
http://adsabs.harvard.edu/abs/2007AGUFM.U13B1150S
http://cgrg.geog.uvic.ca/abstracts/St-OngePreliminaryThe.html

New Images: Pingualuit Crater, Canada
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17919

Google Earth - Chubb Crater / New Quebec Crater /PINGALUIT CRATER
http://bbs.keyhole.com/ubb/showthreaded.php/Number/903182

Laval University Paleolimnology and Paleoecology Laboratory.
Pingualuit Crater Lake Project.
http://www.cen.ulaval.ca/pingualuit/index.html
http://www.cen.ulaval.ca/paleo/Projets/Pingualuit/index.html

University of Arkansas. (2007, December 11) Arctic Impact
Crater Lake Reveals Interglacial Cycles in Sediments.
http://dailyheadlines.uark.edu/11974.htm

Arctic Impact Crater Lake Reveals Interglacial Cycles In Sediments
http://www.sciencedaily.com/releases/2007/12/071215212916.htm

Pingualuit National Park
http://www.fapaq.gouv.qc.ca/en/consultation/pingualuit/

Yours,

Paul H.

Sunday, 31 August 2008

ATTN : Hurricane Gustav Evacuation

ATTN : Hurricane Gustav Evacuation

Paul bristolia at yahoo.com
Sun Aug 31 00:51:35 EDT 2008

Dave Carothers wrote:

"Best of luck, Mike. Having been stationed at Keesler
AFB in Biloxi, I know what you are going through.
God speed."

Some quotes:

"The mother of all storms." and "This is the storm of the century."
- Mayor Ray Nagin.

"This is as worst as it can get." - Gov. Bobby Jindle

They are now predicting that Gustav will be a Category 4 (and
possibly even 5 at times) Hurricane with 15 to 20 foot storm
surge. The coastal areas and parishes are going to get hammered
very, very badly if the predictions come true. In Baton Rouge,
we will definitely be with out power for days at least. The
only saving grace is that being in the northwest side of the
hurricane, the wind will blow any trees in our yard away from
the house if they should fall. Just as long as there are not
any tornadoes, we should be able to ride out what looks to be
a rather rough sleigh ride on Monday. I and Irina have all
of our supplies, money, full tank of gas in both of our cars,
and so forth. Now all we can do is wait and make the remainder
of the preparations. It feels like what it would be like to
know that a medium-size meteorite was headed toward a part
of Earth near me.


>From the looks of it, this will be worst than either Katrina,

Rita, or Andrew, which I have all been through here and from
what I have heard of it, at least either as bad as or worse
than Betsy even as far inland as Baton Rouge, LA.

People are "getting out of Dodge City".

Hurricane Gustav Evacuees Make Way To Chicago
http://cbs2chicago.com/local/hurricane.gustav.hurricane.2.806975.html

Then there is this:

Gustav's potential storm surge could inundate Houma
http://www.dailycomet.com/article/20080830/ARTICLES/808309944/1212&title=Gustav_s_potential_storm_surge_could_inundate_Houma

Gustav could send a 25-foot wall of water into Terrebonne,
Lafourche, meteorologist says
http://www.dailycomet.com/article/20080830/HURBLOG/808300293&title=Gustav_could_send_a_25_foot_wall_of_water_into_Terrebonne__Lafourche__meteorologist_says

Best regards,

Paul

Tuesday, 26 August 2008

Acraman Corrections and Bunyeroos

Acraman Corrections and Bunyeroos

Paul bristolia at yahoo.com
Tue Aug 26 17:29:40 EDT 2008

Sterling K. Webb wrote:

“Don't ask me what a Bunyeroo is... Maybe a relative of
the Bunyip?”

Your guess is as good as mine. :-) :-)

Whatever a Bunyeroo might be, there is a gorge and creek
in the Flinders Ranges of South Australia named after it.

A brief description of the geology, including the Acraman
impact bed exposed in Bunyeroo George can be found in:

Webb, G. 2005. The geology of Bunyeroo, Brachina, and
Parachilna Gorges. In: (eds.) Aikman, A., Lilly, K., Célérier,
J., Kovács, I., and Estermann, G., An excursion guide to the
Flinders Ranges, South Australia, Journal of the Virtual
Explorer, Electronic Edition, ISSN 1441-8142, Volume 20,
Paper 2.

http://virtualexplorer.com.au/journal/2005/20/webb/

Tsunamis and super-hurricanes after the Acraman
asteroid impact

http://www.pir.sa.gov.au/__data/assets/pdf_file/0011/11108/mj39_tsunamis_acraman.pdf

Flinders Ranges National Park Bunyeroo and Wilcolo Creeks Hike

http://www.environment.sa.gov.au/parks/pdfs/BUNYEROO_WILCOLO_HIKE.PDF

Yours,

Paul H.

Downloadable Paper and web Page about Scandinavian Impact Structures

Downloadable Paper and web Page about Scandinavian Impact Structures

Paul bristolia at yahoo.com
Tue Aug 26 13:36:48 EDT 2008

There is online a paper about Scandinavian impact
structures, which can be downloaded for free. It is:

Dypvik, H., J. Plado, C. Heinberg, E. Hakansson, L. J.
Pesonen, B. Schmitz and S. Raiskila, 2008, Impact
structures and events – a Nordic perspective. Episodes.
vol. 31, no. 1, pp. 107-114.

It can be downloaded from

http://www.episodes.org/backissues/33igc/15%20Impact%20%20structures-r.pdf

The link to this paper and table of contents for the issue
of Episodes containing it can be found at:

http://www.episodes.org/backissues/33igc/33igc.htm

Also, there is "Store runde strukturer i norsk natur" at:

http://www.geo.uio.no/groper/

Yours,

Paul H.

Monday, 18 August 2008

Meteorite impact structures: the good and the bad

Meteorite impact structures: the good and the bad

Paul bristolia at yahoo.com
Mon Aug 18 09:15:01 EDT 2008

While looking for something else I came across a general article
about impact structures. It is:

Osinsk, G. R., 1999, Meteorite impact structures: the good and
the bad. Geology Today. vol. 24, no. 1, pp. 13-19.

The PDF file is at:

http://www3.interscience.wiley.com/cgi-bin/fulltext/119400823/PDFSTART

The abstract is at:

http://www3.interscience.wiley.com/journal/119400823/abstract

Yours,

Paul H.

Sahara Paleoclimate was "When the Sahara was wetter (relevant to your interests)"

Sahara Paleoclimate was "When the Sahara was wetter (relevant to your interests)"

Paul bristolia at yahoo.com
Mon Aug 18 00:09:02 EDT 2008

David Garrison wrote:

" http://i45.photobucket.com/albums/f79/bougainvillea1/Relevant_to_interests_hedgehog.jpg

How wet and for how long and how recently the Sahara
was wet of course is a determining factor in the ages
of the older Saharaian meteorites. (of course the 1,000
years ago is an error on the part of the article writer

http://www.msnbc.msn.com/id/26203952/

Remains of cemetery found in Sahara A thousand
years ago, the now-barren desert was moist and
green By Randolph E. Schmid updated 6:28 p.m.
ET, Thurs., Aug. 14, 2008"

The dissication of the Sahara Desert is discussed in
"Climate and environmental history of the Sahara: the
last 6000 years" by Dr.Patrick Honecker at:

http://www.pressoffice.uni-koeln.de/1651+M5f856bfc5ae.html

He states:

"The results of this work document a progressive drying
of the regional terrestrial ecosystem between 5600 and
2700 years ago, in response to gradually decreasing
tropical monsoon rainfall. This drying followed a logical
ecological sequence starting with tropical grassland trees
and herbs being replaced by typical Sahel vegetation,
followed by loss of grass cover and establishment of
the modern desert plant community that is largely
restricted to oases."

and

"In summary, this new environmental reconstruction from
within the Sahara proper strongly contrasts with the
generally accepted hypothesis that the ‘green Sahara’
which existed between 10,000 and ~6000 years ago had ended
abruptly."

The paper ("work") discussing the paleoclimatology of the
Sahara Desert is:

Francus, P., J.-P. Cazet, M. Fagot, B. Rumes, J. M. Russell,
F. Darius, D. J. Conley, M. Schuster, H. von Suchodoletz, and
D. R. Engstrom, 2008 Climate-Driven Ecosystem Succession in
the Sahara: The Past 6000 Years. Science. vol. 320, no. 5877,
pp. 765-768.

The abstract to this paper can be found at:

http://www.sciencemag.org/cgi/content/abstract/320/5877/765
http://www.ncbi.nlm.nih.gov/pubmed/18467583?dopt=Abstract

Their paleoenvironmental reconstruction of the pollen from a
continuous core covering 6000-year from northern Chad indicates
a "progressive drying of the regional terrestrial ecosystem"
that resulted in strong reductions in tropical trees and then
Sahelian grassland cover" and "large-scale dust mobilization"
starting about 4300 calendar years before the present. They
concluded that "today's desert ecosystem and regional wind
regime were established around 2700 calendar years before
the present."

A PDF file of this paper can be found at:

http://www.old.uni-bayreuth.de/departments/geomorph/docs/Kroepelinetal_2008.pdf

A discussion of this paper can be found in "Study:
Sahara Gradually Dried Up Over 6,000 Years" at:

http://www.npr.org/templates/story/story.php?storyId=90289718

Another recent paper about the paleoclimatology of the
Sahara Desert is;

Bubenzer1, O., and H. Riemer, 2007, Holocene Climatic
Change and Human Settlement Between the Central Sahara
and the Nile Valley: Archaeological and Geomorphological
Results. Geoarchaeology, vol. 22, no. 6, 607–620.

For the eastern Sahara, they conclude:

"The evidence derived from archaeological excavations and
surveys coupled to nearly 500 14C dates (Figure 2) suggests
that the Holocene wet phase lasted from approximately
9500–6000 B.P. (9000–5000 cal. B.C., calibration: dispersion
calibration program, Cologne 2001, www.calpal.de). After
the hyper-arid Pleistocene, the tropical summer rain front
moved about 700–1000 km northward (e.g., Haynes, 1987;
Neumann, 1989a; Pachur and Hoelzmann, 2000), which
initiated more humid conditions in the Eastern Sahara."

Notice that the Pleistocene before 9,500 BP was hyper-arid
and the "wet" Sahara was only from 9500–6000 B.P.

An interesting web page on this topic is "Africa During the
Last 150,000 Years" by Jonathan Adams at:

http://www.esd.ornl.gov/projects/qen/nercAFRICA.html
http://www.esd.ornl.gov/projects/qen/new_africa.html
http://www.esd.ornl.gov/projects/qen/refs.html

This is what he has to say about the Sahara:

"(dates in Guo et al are given in 14C years ago on the
left, approximate calibrated of 'real' dates are given
on the right)

Moist 9,500-8,200 14C ya (10,400-9,100 ya)
Slight drying 8,200-8,000 14C ya (9,100-8,900 ya)
Moist 8,000-7,000 14C ya (8,900-7,900 ya)
Moderately dry 7,000-5,700 14C ya (7,900-6,500 ya)
Moist 5,700-4,000 14C ya (6,500-4,500 ya)
Very dry - as dry as at present - 4,000-3,800 14C ya (4,500-4,100 ya)
Slightly moister than present 3,800-3,500 14C ya (4,100-3,700 ya)
After 3,500 14C ya (3,700 ya). Remaining about as dry as at present"

Yours,

Paul H.

Sunday, 17 August 2008

Russian Sikhote Aline Meteorite Film

Russian Sikhote Aline Meteorite Film

Paul bristolia at yahoo.com
Sun Aug 17 23:14:32 EDT 2008

Dear Friends,

While looking for something else, I came across the below Russian
meteorite film in the Library of Congress Cataloge.

"THE SIKHOTE ALINE METEORITE (1956) FEA 1315-16
Central Documentary Film Studio 35mm
Dir: I. Gradov, Consultant: V. Fesenkov

A well-photographed documentary film on the scientific
investigation of the Sikhote Aline Meteorite that fell in Siberia in
1947. Print is in good shape, with one splice. Probably of most
interest to specialists, either in meteorology or those interested in
Soviet scientific methods in the late 1940s.

English track."

http://www.loc.gov/rr/mopic/findaid/russian.html

Yours,

Paul H.


Thursday, 14 August 2008

It came from the sky: school rock an ancient meteorite (Australia)

It came from the sky: school rock an ancient meteorite (Australia)

Paul bristolia at yahoo.com
Thu Aug 14 23:05:57 EDT 2008

It came from the sky: school rock an ancient meteorite
by Dimity Barber, Berwick leader, August 14, 2008

http://www.berwickleader.com.au/article/2008/08/13/41154_blv_news.html

The first few sentences states:

"CLYDE Primary School has been rocked by news it is the
custodian of a 4.5 billion-year-old meteorite.

Principal Maurie Richardson said the school had received word from Museum Victoria that an 85kg rock now on display at the school is a fragment of Cranbourne’s world-famous meteorite shower."

...rest of text omitted...

More Photographs of Meteorite

http://tools.leadernewspapers.com.au/photo_galleries/gallery.php?id=1375

Yours,

Paul H.

Wednesday, 13 August 2008

Articles on Impact Caused "megatsunami chevrons" and URL Correction

Articles on Impact Caused "megatsunami chevrons" and URL Correction

Paul bristolia at yahoo.com
Wed Aug 13 23:59:48 EDT 2008

First, I found a couple of very interesting articles about the
alleged "'megatsunami chevrons", which are argued to have
been caused by megatsunamis by Dallas Abbott (at Lamont
Doherty Earth Observatory) and her co-workers. The articles
are:

1. Some questions about the 'megatsunami-chevrons' at
http://zsylvester.blogspot.com/2008/03/some-questions-about-megatsunami.html

and 2. Some questions about the 'megatsunami chevrons':
addendum at:

http://zsylvester.blogspot.com/2008/05/some-questions-about-megatsunami.html

in addition, one of the URLs does not work in my last post,
"[meteorite-list] Re Here We Go Again About Terminal
Pleistocene Impact" at:

http://six.pairlist.net/pipermail/meteorite-list/2008-August/046160.html

The URL for "States and Stability of Climate System", PDF file,
should be:

http://www.iac.ethz.ch/education/bachelor/climate_systems/notizen/Climate-States-and-Stability.pdf

It discusses the Younger Dryas.

Yours,

Paul H.

Re Here We Go Again About Terminal Plesitocene Impact

Re: Here We Go Again About Terminal Pleistocene Impact

Paul bristolia at yahoo.com
Wed Aug 13 23:21:14 EDT 2008

In http://six.pairlist.net/pipermail/meteorite-list/2008-August/046148.html ,
Darren Garrison noted the article “Comet strike would be cataclysmic” at:

http://www.thisiswesternmorningnews.co.uk/news/Comet-strike-end-world-scenario/article-265193-detail/article.html

The article states:

“Fiery debris from the comet also melted
huge portions of the ice sheet, which
drastically altered the planet's climate.
Massive volumes of fresh water found
their way into the oceans and changed
their currents, plunging the Earth into
an Ice Age for 1,000 years.”

It is interesting to note that Dyke (2004) made a detailed study of
the deglaciation of North America. As a part of this study, he
constructed and published in this paper a series of detailed
paleogeographic maps showing the extent of ice starting at 18,000
C14 BP and ending at 5,000 C14 BP. for time periods ranging from
500 to 100 years.

From calculating ice volumes using these paleogeographic
maps Dyke (2004) states:

“The world’s largest ice sheet complex lost
<10% of its area prior to 14 ka BP. It then
retreated nearly linearly until 7 ka BP, by
which time only 10% of the area remained
more glaciated than today. This linear
reduction of area, as currently understood,
was interrupted by two events: a reduced
rate of recession during the later half of the
Younger Dryas, and an increased rate as ice
was clearing from Hudson Bay (Fig. 5).
These events are clearer when plotted on
the calendar time scale, because the
radiocarbon time scale abbreviates the
duration of the impact of the Younger Dryas
effect in North America (Fig. 5b).”

At the beginning of the Younger Dryas, Dyke (2004) shows a lack
of any abrupt increase in the retreat (melting) of the North American
ice sheet. So far, the proponents of this theory have provided a
single shred of evidence that massive melting of the ice sheets, as
described in the newspaper article, actually occurred.

There is significance evidence of the discharge of large amounts
of freshwater from either Lake Agassiz, the melting of the Keewatin
ice dome, or combination of both sufficient to shut down
thermohaline circulation within the Atlantic Ocean, i.e. Alley (2000),
Broecker (2003), and Tarasov and Peltier (2006). The water
contained by Lake Agassiz was already there and was simply
released, not created, abruptly.

References:

Alley, R.B., 2000, The Younger Dryas cold interval as
viewed from central Greenland. Quaternary Science
Reviews. vol. 19, no. 1-5, pp. 213-226.

Broecker, W.S., 2003, Does the Trigger for Abrupt
Climate Change Reside in the Ocean or in the Atmosphere?
Science. vol. 300, pp. 1519-1522.

Dyke, 2004 A.S. Dyke, An outline of North American
deglaciation with emphasis on central and northern Canada.
In: J. Ehlers and P.L. Gibbard, EDS., pp. 373–424,
Quaternary Glaciations—Extent and Chronology, Part II
vol. 2b, Elsevier, Amsterdam.

Tarasov , L., and W.R. Peltier, 2005, A calibrated deglacial
drainage chronology for the North American continent:
evidence of an Arctic trigger for the Younger Dryas.
Quaternary Science Reviews. vol. 25, pp. 659–688

Also, look at:

States and Stability of Climate System, PDF file at:

http://www.iac.ethz.ch/education/bachelor/climate_systems/notizen/Climate-States-and-Stability.pdf.

The newspaper article also stated:

“It left no impact crater but sparked the
biggest wildfires in history, which stretched
across the continent and suffocated humans
and animals with overwhelming amounts
of soot and smoke, leaving the few survivors
with no vegetation or prey to live on.

The just published paper, which I mention in my previous post
comments on this claims. The paper is;

Buchanan, B., M. Collard, and K. Edinborough, 2008,
Paleoindian demography and the extraterrestrial impact
hypothesis. Proceedings of the National Academy of
Sciences. Published online before print August 12,
2008, doi: 10.1073/pnas.0803762105

http://www.pnas.org/content/early/2008/08/11/0803762105.abstract

They noted:

"Given that the ET impact is proposed to have
occurred north of the Great Lakes, if the trough
represents a population decline, there should be
significantly fewer Paleoindian radiocarbon dates in
northern latitudes during the second time period
compared with the first and third time periods.
This is not the case."

They concluded:

"The results of our analysis are consistent with recent
comments by Pinter and Ishman (13) and Haynes (14).
Pinter and Ishman reject Firestone et al.’s (1) claim
that there was a devastating ET impact north of the
Great Lakes at 12,900+/-100 calBP."

and

“The results of the analyses were not consistent
with the predictions of extraterrestrial impact
hypothesis. No evidence of a population decline
among the Paleoindians at 12,900 ± 100 cal BP
was found.”

Note:

"Pinter and Ishman (13)" = Pinter, N., and S. E. Ishman, 2007,
Impacts, mega-tsunami, and other extraordinary claims. GSA
Today. vol. 18, no. 1, pp. 37-38.

http://www.gsajournals.org/archive/1052-5173/18/1/pdf/i1052-5173-18-1-37.pdf

Also look at figure 4 at:

http://www.hallofmaat.com/images/004Fig.jpg

Notice there were three major periods of rapid vegetational change
in the northeast Midwest and southeast United States as indicated
by the green lines, None of them correspond to Firestone’s
hypothesized impact. There is a complete lack of any evidence in
the paleovegetation records from numerous lake cores in these
areas for Firestone’s hypothesized impacts. Given the claims
made for the size, magnitude, and devastation of his hypothesize
impact, it is impossible for entire ecosystems to have been
devastated by continent-wide wildfires and not significantly changed
the vegetation in an abrupt manner The lack of any apparent effect
on vegetation in North America as illustrated by Jacobson et al.
(1987) grossly contradicts, if not refutes, the geopoetry, which
appears in this newspaper article, about continent-wide
devastating wildfires.

References cited:

Jacobson, George L., Jr., Webb, Thompson, III, and Grimm,
Eric E., 1987, Patterns and rates of vegetational change
during the deglaciation of North America. in W. F. Ruddiman
and H. E. Wright, Jr., eds., pp. 277-287. North America
Adjacent Oceans During the Last Deglaciation. The Geology
of North America. vol. K-3. Geological Society of America,
Boulder, Colorado.

Yours,

Paul H.