'Chevrons' Are Not Evidence Of Megatsunamis

Paul bristolia at yahoo.com
Thu Apr 30 20:37:41 EDT 2009

Past Tsunamis? Contrary To Recent Hypothesis, 'Chevrons'
Are Not Evidence Of Megatsunamis, Science Daily, April 30, 2009,
http://www.sciencedaily.com/releases/2009/04/090429091637.htm

Contrary to recent hypothesis, 'chevrons' are not evidence
of megatsunamis by Vince Stricherz, University of Washington,
http://uwnews.washington.edu/ni/article.asp?articleID=49190

Yours,

Paul H.

Papers on the Araguainh Impact Structure (Brazil) and Permian Extinction

Paul bristolia at yahoo.com
Tue Apr 28 23:24:47 EDT 2009

Below are some papers about the Araguainh Impact Structure.

Lana, C., R. Romano, W. U. Reimold, and J. Hippertt, 2006,
Collapse of large complex impact craters: Implications from
the Araguainha impact structure, central Brazil. Geology.
vol. 34, no. 1, pp. 9–12.

http://geology.geoscienceworld.org/cgi/content/abstract/34/1/9


Lana, C., and Y. Marangoni, 2009, The Araguainha impact:
a South American Permo–Triassic catastrophic event.
Geology Today. vol. 25 , no. 1, pp. 21-28.

http://www3.interscience.wiley.com/journal/121659122/abstract


Lana, C., C. R. S. . Filho, Y. R. Marangoni, E. Yokoyama,
R. I. F. Trindade, E. Tohver, and W. U. Reimold, 2008,
Structural evolution of the 40 km wide Araguainha impact
structure, central Brazil. Meteoritics & Planetary Science.
vol. 43, no. 4, pp. 701–716

https://digitalcommons.library.arizona.edu/objectviewer?o=uadc%3A%2F%2Fazu_maps%2FVolume43%2FNumber4%2Fb4c801ae-1277-4c90-aa90-88feae2679b6

and

http://bulletin.geoscienceworld.org/cgi/content/abstract/119/9-10/1135


Lana, C., C. R. S. Filho, Y. R. Marangoni, E. Yokoyama,
R.I.F. Trindade, E. Tohver, and W.U. Reimold, 2007, Insights
into the morphology, geometry, and post-impact erosion of the
Araguainha peak-ring structure, central Brazil. Geological
Society of America Bulletin. vol. 119, no. 9-10, pp. 1135-1150
DOI: 10.1130/B26142.

http://bulletin.geoscienceworld.org/cgi/content/abstract/119/9-10/1135


Mutter, J. R., H. Z. Tomassi, and D. A. do Carmo, 2008,
In pursuit of causes for the greatest mass extinction: the
Permo-Triassic Boundary in the Southern Hemisphere – part
II: : investigating 260 Million Years Old, Meteorite-
impacted Sedimentary Rocks In Central-west Brazil.
Vierteljahrsschrift der Naturforschenden Gesellschaft
in Zürich. vol. 153, no. ¾, pp. 81–91.

http://www.tomassi.net78.net/web_documents/mutter_tomassi_docarmo_2008.pdf

Yours,

Paul H.

Where to Look for Meteorites

Paul bristolia at yahoo.com
Tue Apr 28 16:13:18 EDT 2009

Below is a paper and a web page that might provide some
hints as to where to look for meteorites.

Matmon, A., O. Simhai, R. Amit, I. Haviv, N. Porat, E. McDonald,
L. Benedetti, and R. Finkel, 2009, Desert pavement–coated
surfaces in extreme deserts present the longest-lived landforms
on Earth. Geological Society of America Bulletin. v. 121, no. 5-6,
p. 688-697. doi:10.1130/B26422.1

http://gsabulletin.gsapubs.org/cgi/content/abstract/121/5-6/688

A related web page is “Matmon Ari Research Interests” at:

http://earth.huji.ac.il/staff-details.asp?topic=0&id=323

“Paran Plains, a typical environment in the Near East … The
combined surface and subsurface samples indicate that the
surface and its particles have not eroded for millions of years.”

http://earth.huji.ac.il/Data/Image/Ari/Paran%20Plains.jpg

The above web page also has a picture of a small erosional crater. at:

http://earth.huji.ac.il/Data/Image/Ari/Makhtesh%20Katan.jpg

“A small (4X5 km2) erosional crater (Makhtesh Katan). Active
channel sediment, sediment from Pleistocene terraces, and
bedrock samples were collected for cosmogenic isotope
analyses. Preliminary results suggest a cliff retreat rate and
enlargement of the crater at a rate of ~70 m/Ma.”

Yours,

Paul H.

Correction To "The Usselo Soil and the Younger Dryas Extraterrestrial Impact Hypothesis"

Paul bristolia at yahoo.com
Mon Apr 27 12:11:37 EDT 2009

I need to correct my previous post, "The Usselo Soil and the Younger
Dryas Extraterrestrial Impact Hypothesis". Its third paragraph should
read:

"One important point that this paper makes is that what
has been called either the “Usselo Horizon” or “Usselo
Layer” is not a "layer" in terms of being a tabular
depositional body of either rock or unconsolidated sediment
created separately from the sediments above and below it.
Rather, it is a relict, buried Albic Arenosol and Brunic
Arenosol (paleosol) that developed in preexisting sediment
as the result of a period of surface weathering during a
period of nondeposition. As a paleosol, it is pedolostratigraphic
marker horizon, not a depositional horizon as some
proponents of the Younger Dryas extraterrestrial impact
hypothesis imply by the use of the term “horizon”."

the first paragraph should read:

"A new paper, which in press in “Boreas” about the
Usselo Soil and the Younger Dryas extraterrestrial impact
hypothesis, has recently appeared. It is:"

I apologize for not being a better editor.

Best regards,

Paul H.

The Usselo Soil and the Younger Dryas Extraterrestrial Impact Hypothesis

Paul bristolia at yahoo.com
Mon Apr 27 12:00:25 EDT 2009

A new paper, which in press in “Boreas”, about the
Usselo Soil and the Younger Dryas extraterrestrial impact
hypothesis has recently appeared. It is:

Kaiser, K. H., A., N. Schlaak, M. Jankowski, M, P. Kuhn,
S. Bussemer, K. Przegietka, in press, Palaeopedological
marker horizons in northern central Europe: characteristics
of Lateglacial Usselo and Finow soils. Boreas.
Doi: 10.1111/j.1502-3885.2008.00076.x. ISSN 0300-9483
http://www3.interscience.wiley.com/journal/121660907/abstract

One important point that this paper makes is that what
has been called either the “Usselo Horizon” or “Usselo
Layer” in terms of being a tabular depositional body of
either rock or unconsolidated sediment created separately
from the sediments above and below it. Rather, it is a relict,
buried Albic Arenosol and Brunic Arenosol (paleosol)
that developed in preexisting sediment as the result of a
period of surface weathering during a period of
nondeposition. As a paleosol, it is pedolostratigraphic
marker horizon, not a depositional horizon as some
proponents of the Younger Dryas extraterrestrial impact
hypothesis imply the Usselo Soil by the use of the term
“horizon”.

Another important points this paper makes is that like
any paleosol, the Usselo Soil and its correlative Finow
Soil are time-transgressive in terms of when their burial
ended the period of weathering and soil formation that
created these paleosols. Radiocarbon dates from the
Usselo Soil represent all of the Allerod and Younger
Dryas age with a few outlier dates of Preboreal age.
Thus, both paleosols represent a variable period of
nondeposition encompassing the Allerod age and
the Allerod and Younger Dryas ages depending on
specific location that is examined. Thus, the Osselo Soil
cannot be an event bed created during a single
instantaneous event. Instead, it is a paleosol that reflects
nondeposition over a variable period of time that varies
between 1,000 and 1,500 years in length.

This paper also presents a number of optically stimulated
luminescence (OSL) dates of eolian sand overlying the
Usselo Soil. These OSL dates demonstrate that within
some parts of the area, in which the Usselo Soil occurs, it
was initially buried by eolian sands of late Allerod age.
Thus, at several locations, the Usselo Soil predates the
Allerod-Younger Dryas boundary and it is impossible for
the Usselo Soil at several locations be to connected with
any Allerod-Younger Dryas boundary event of any type.

Some other papers about the Usselo Soil (Usselo Layer /
Horizon), are:

Bertran, P., G. Ge. Allenet, T., F. Naughton, P. Poirier, M. F.
and Goni, 2009. Coversand and Pleistocene palaeosols
in the Landes region, southwestern France. Journal of
Quaternary Science. no. 3, vol. 24 pp. 259–269.
http://www3.interscience.wiley.com/journal/121448008/abstract

Derese, C. D. Vandenberghe, E. Paulissen, P. V. den Haute, in
press, Revisiting a type locality for Late Glacial aeolian sand
deposition in NW Europe: Optical dating of the dune complex
at Opgrimbie (NE Belgium). Geomorphology.
http://dx.doi.org/10.1016/j.geomorph.2008.08.022

Hoek, W. Z., 1997, Paleogeography of Lateglacial vegetations:
Aspects of Lateglacial and Early Holocene vegetation, abiotic
landscape, and climate in The Netherland. Ook verschenen als
handelsed.: Utrecht: Koninklijk Nederlands Aardrijkskundig
Genootschap (Nederlandse Geografische Studies,
ISSN 0169-4839 ; 230) Proefschrift Vrije Universiteit
Amsterdam.
http://dare.ubvu.vu.nl/handle/1871/12731
http://dare.ubvu.vu.nl/bitstream/1871/12731/1/tekst.pdf
http://dare.ubvu.vu.nl/bitstream/1871/12731/2/bijlage.pdf

Hoek, W. Z., and S. J. P. Bohncke, 2002, Climatic and
environmental events over the Last Termination, as recorded
in The Netherlands: a review. Netherlands Journal of
Geosciences (Geologie en Mijnbouw) vol. 81, no. 1, pp. 123-137
http://www.njgonline.nl/publish/articles/000199/english.html
http://www.njgonline.nl/publish/articles/000199/article.pdf

Kasse, C., 1997, Cold-Climate Aeolian Sand-Sheet Formation
in North-Western Europe (c. 14±12.4 ka); a Response to
Permafrost Degradation and Increased Aridity. Permafrost and
Periglacial Processes. vol. 8, pp. 295-311.
http://www3.interscience.wiley.com/journal/14077/abstract

Kasse, C., 2002, Sandy aeolian deposits and environments
and their relation to climate during the Last Glacial Maximum
and Lateglacial in northwest and central Europe. Progress in
Physical Geography. vol. 26, no. 4, pp. 507-532.
http://ppg.sagepub.com/cgi/content/refs/26/4/507

Kasse, C., D. Vandenberghe, F. De Corte, and P. Van den
Haute, 2007, Late Weichselian fluvio-aeolian sands and
coversands of the type locality Grubbenvorst (southern
Netherlands): sedimentary environments, climate record and
age. Journal of Quaternary Science. vol. 22, pp. 695–708.
http://www3.interscience.wiley.com/journal/114185744/abstract

van der Hammen, T., and B. van Geel, 2008, Charcoal in
soils of the Allerød-Younger Dryas transition were the
result of natural fires and not necessarily the effect of
an extra-terrestrial impact. Netherlands Journal of
Geosciences. vol. 8. no. 4, pp. 359-361
http://www.njgonline.nl/publish/articles/000404/english.html
http://www.imep-cnrs.com/docu/charcoal.pdf

Yours,

Paul H.

PDF File of Dissertation About Shock Metamorphism at Meteor Crater Available Online

Paul bristolia at yahoo.com
Thu Apr 16 00:55:19 EDT 2009

Dear Friends,

A PhD dissertation about the shock metamorphism of Coconino
Sandstone at Meteor Crater can be downloaded as a PDF file.

It is;

Kieffer, Susan W., 1970, I. Shock metamorphism of the Coconino
sandstone at Meteor Crater, Arizona. II. The specific heat of
solids of geophysical interest. Unpublished PhD dissertation,
California Institute of technology, Pasadena, California.

The abstract and link to PDf file can be found at:

http://etd.caltech.edu/etd/available/etd-06232004-134838/

The 10.5 MB PDF file can downloaded directly from:

http://etd.caltech.edu/etd/available/etd-06232004-134838/unrestricted/Kieffer_sw_1971.pdf

Yours,

Paul H.

Black Diamonds: A interesting PBS NOVA article

Paul bristolia at yahoo.com
Sun Apr 12 22:23:49 EDT 2009

Personally, I do not know what to think about the
origin of carbonados. I do think that "there is much
contradictory evidence in the literature" and "This
is conundrum which still calls for much more research."
to quote from the abstract of:

McCall, G.J.H., 2009, The carbonado diamond conundrum.
Earth-Science Reviews. vol. 93, no. 3-4, pp. 85-91.
http://dx.doi.org/10.1016/j.earscirev.2009.01.002

Whatever happened to create carbonados, happened a
very long time ago as discussed by:

Yuji, S., R. Yokochia, K. Teradab, M.L. Chaves, and
M. Ozimad, 2002, Ion microprobe Pb-Pb dating of
carbonado, polycrystalline diamond. Precambrian
Research. vol. 113, no. 1-2, pp. 155-168
http://dx.doi.org/10.1016/S0301-9268(01)00208-X

Some quotes from Yuji et al. (2002).

"Pb–Pb age of mineral inclusions in GM01 carbonado,
3.3+/-0.7 Ga is older than the formation age of the
Sopa conglomerate in carbonado-bearing deposit
related to the first extensional event in southeast
border of the Sao Francisco craton at 1750–1700 Ma
(Uhlein et al., 1998). Therefore, the carbonados
were originated somewhere else and later incorporated
in the Sopa conglomerate."

"Mineral inclusions (rutile, florencite, quartz,
zircon, and clay minerals) of GM01 and DO3
carbonados are typically crustal. The upper mantle
origin of the carbonados may be, therefore, ruled out."

"In addition we can not find any evidence of high
pressure shock-metamorphism such as occurrence
of coesite based on the mineral assemblage of the
carbonado inclusions. Therefore, the early impact
origin of the carbonados is probably excluded."

"207Pb/206Pb isochron age of DO3 carbonado
matrix is consistent with that of Central African
carbonado reported by other workers, suggesting
a close genetic relationship between Brazilian and
African carbonados within a united landmass
during the Archean, as supported by 3.6 Ga zircons
observed in the conglomerate.

With the contradictory evidence for their origin,
the lack of any carbonados being found in place where
they formed, and their great age, it might be very
difficult to understand exactly how they formed.
Because of their great age and having been eroded
and redeposited from the parent strata in which they
either form in place or accumulated as debris from
some extraterrestrial event means a lot of the
critical evidence concerning their origin has been
lost.

Yours,

Paul H.

Black Diamonds: A interesting PBS NOVA article

Paul bristolia at yahoo.com
Fri Apr 10 23:15:49 EDT 2009

Steve Schoner wrote:

"Here is a very interesting PBS article on carbonados.

http://www.pbs.org/wgbh/nova/diamond/sky2.html "

Also look at:

Kagi, H. and S. Fukura, 2008, Infrared and Raman spectroscopic
observations of Central African carbonado and implications for
its origin. European Journal of Mineralogy. vol. 20, no. 3,
pp. 387-393, DOI: 10.1127/0935-1221/2008/0020-1817
http://eurjmin.geoscienceworld.org/cgi/content/abstract/20/3/387

McCall, G.J.H., 2009, The carbonado diamond conundrum.
Earth-Science Reviews. vol. 93, no. 3-4, pp. 85–91.
http://dx.doi.org/10.1016/j.earscirev.2009.01.002

Yokochi, R., D. Ohnenstetter, and Y. Sano, 2008, Intragrain
Variation in g13C And Nitrogen Concentration Associated
with Textural Heterogeneities of Carbonado. The Canadian
Mineralogist. vol. 46, no. 5, pp. 1283-1296, DOI: 10.3749/canmin.46.5.1283
http://canmin.geoscienceworld.org/cgi/content/abstract/46/5/1283

Diamonds, II: Diamond and Carbonado: Crystal Habits and Surface Morphology
http://www.turnstone.ca/diamond2.htm

Yours,

Paul H.

Gamma Ray Burst caused mass extinction? (With URLs to PDF Files)

Paul bristolia at yahoo.com
Fri Apr 10 23:10:48 EDT 2009

Gamma-Ray Burst Caused Mass Extinction? Anne Minard
National Geographic News, April 3, 2009,
http://news.nationalgeographic.com/news/2009/04/090403-gamma-ray-extinction.html

There are a number of papers about this hypothesis.

Melott, A.L., B.S. Lieberman, C.M. Laird, L.D. Martin,
M.V. Medvedev, B.C. Thomas, J.K. Cannizzo, N. Gehrels,
and C.H. Jackman, 2004, Did a gamma-ray burst initiate
the late Ordovician mass extinction? International
Journal of Astrobiology, vol. 3, pp. 55-61.
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=240775

The PDF file is at http://arxiv.org/pdf/astro-ph/0309415

Thomas, B.C. C.H.. Jackman, A.L. Melott, C.M. Laird, RS.
Stolarski, N. Gehrels, J.K. Cannizzo, and D.P. Hogan, 2005.
Terrestrial Ozone Depletion due to a Milky Way Gamma Ray
Burst. The Astrophysical Journal Letters. vol. 622, no. 2,
pp. L153–L156.
http://www.journals.uchicago.edu/doi/abs/10.1086/429799


The PDF file is at http://arxiv.org/pdf/astro-ph/0411284

Dar, A. and A. De Rujula, 2002, The threat to life from
Eta Carinae and gamma ray bursts. Astrophysics and
Gamma Ray Physics in Space. Frascati Physics Series Vol. 24
pp. 513-523 http://arxiv.org/abs/astro-ph/0110162

PDF file at http://arxiv.org/pdf/astro-ph/0110162v2

Thomas, B.C., A.L. Melott1, C.H. Jackman, C.M. Laird, M.V.
Medvedev, R.S.. Stolarski, N. Gehrels, J.K. Cannizzo, D.P.
Hogan, and L.M. Ejzak, 2005, Gamma-Ray Bursts and the
Earth: Exploration of Atmospheric, Biological, Climatic and
Biogeochemical Effects. The Astrophysical Journal.
vol. 634, pp. 509-533 http://arxiv.org/abs/astro-ph/0505472

PDF file at http://arxiv.org/pdf/astro-ph/0505472

A.L. Melott and B.C.Thomas, Late Ordovician geographic
patterns of extinction compared with simulations of
astrophysical ionizing radiation damage.

PDf file at http://arxiv.org/pdf/0809.0899

Gamma-Ray Bursts as a Threat to Life on Earth
by B. C. Thomas. http://arxiv.org/pdf/0903.4710

Gamma-ray burst
http://en.wikipedia.org/wiki/Gamma_ray_burst

Yours,

Paul H.

STEREO Hunts for Remains of an Ancient Planet near Earth

Paul bristolia at yahoo.com
Fri Apr 10 23:06:40 EDT 2009

Ron Baalke posted:

" http://science.nasa.gov/headlines/y2009/09apr_theia.htm?list973415

STEREO Hunts for Remains of an Ancient Planet near Earth
NASA Science News, April 9, 2009"

Some additional papers and articles are:

Stereo spacecraft set to search for lunar origins By Pete
Spotts, Christian Science Monitor,

http://features.csmonitor.com/discoveries/2009/04/10/stereo-spacecraft-set-to-search-for-lunar-leftovers/

Giant impact hypothesis, http://en.wikipedia.org/wiki/Giant_impact_hypothesis

The Origin of the Moon and the Single Impact Hypothesis
by A. G. W. Cameron

http://www.xtec.es/recursos/astronom/moon/camerone.htm

The Theia Hypothesis: New Evidence Emerges that Earth and
Moon Were Once the Same, July 05, 2007,

http://www.dailygalaxy.com/my_weblog/2007/07/the-theia-hypot.html

O'Neill, H.S., 2007, Bowen Lecture: The origin of the Moon
and the early history the Earth revisited

http://www.agu.org/cgi-bin/SFgate/SFgate?&listenv=table&multiple=1&range=1&directget=1&application

Halliday, A. N., 2008, A young Moon-forming giant impact at
70–110 million years accompanied by late-stage mixing, core
formation and degassing of the Earth. Philosophical
transactions of the Royal Society A. vol. 366, no. 1883,
pp. 4163-4181. Abstract at:

http://rsta.royalsocietypublishing.org/content/366/1883/4163.abstract

PDF file of paper at

http://rsta.royalsocietypublishing.org/content/366/1883/4163.full.pdf+html

Yours,

Paul H.

Microtektites from Antarctica

Paul bristolia at yahoo.com
Fri Apr 3 17:45:55 EDT 2009

McCall, J., 2008, Microtektites from Antarctica
Geoscientist 18.8 September 2008

http://www.geolsoc.org.uk/gsl/geoscientist/geonews/page4229.html

Yours,

Paul H.

Crater impostor unmasked as sheep-dip

Paul bristolia at yahoo.com
Fri Apr 3 17:56:24 EDT 2009

Crater impostor unmasked as sheep-dip

"The supposed meteorite that supposedly caused the
supposed “Sirente crater” in the Abruzzi mountains
did not bring down the Roman Empire after all. Ted
Nield reports. Geoscientist Online 19 March 2009"

http://www.geolsoc.org.uk/gsl/geoscientist/geonews/page5368.html

The references given in this article are:

Bondre, N 2009: Crater or not? Nature Geoscience vol. 2 March 2009 p. 166

Ormö J et al., 2002: The Sirente Crater Field, Italy. Meteorit.
Planet. Sci., 37 1507-1521
http://articles.adsabs.harvard.edu/full/2002M%26PS...37.1507O

Speranza, F et al., 2004: An anthropogenic origin of the “Sirente
Crater”, Abruzzi, Italy. Meteorit. Planet. Sci., 39, 4, 635-649
http://www.earth-prints.org/handle/2122/3941

Speranza, F et al., 2009: The “Sirente crater field”, Italy,
revisited. Journal of Geophysical Research. vol. 114, B03103,
doi:10.1029/2008JB005759.
http://www.agu.org/pubs/crossref/2009/2008JB005759.shtml

Yours,

Paul H.

ALICES Tr3k3Δ

Mysterious White Rabbit Comes & Goes in Time
------------------------------------------------------------------------------

NOVA: Comet Airburst Destruction

Paul bristolia at yahoo.com
Tue Mar 31 23:17:38 EDT 2009

Keith wrote


>On PBS tonight in the US is about Meteorite impacts

>on Earth or see it online at pbs.org/nova , NOVA: Comet

>Airburst Destruction

>

>See how explosion three miles above Earth would act

>like a white-hot tornado on the surface. .

>

> http://www.youtube.com/watch?v=bbKIbPKWo2c&feature=channel_page


Also, there is the Libyan Desert Glass and the mysteriously
craterless Australasian tektite field, which the above URLs
need to be kept in mind, while contemplating.

Best Wishes

Paul H.

Did Giant Salt Lakes Cause Permian Mass Extinction ???

Paul bristolia at yahoo.com
Tue Mar 31 23:09:44 EDT 2009

New Theory On Largest Known Mass Extinction In Earth's
History: The largest mass extinction in the history of
the earth could have been triggered off by giant salt
lakes, whose emissions of halogenated gases changed the
atmospheric composition so dramatically that vegetation
was irretrievably damaged, Science Daily, March 31, 2009,

http://www.sciencedaily.com/releases/2009/03/090330102659.htm

New theory on largest known mass extinction in the history
of the earth. Did volatile halogenated gases from giant
salt lakes at the end of the Permian Age lead to a mass
extinction of species?

http://www.ufz.de/index.php?en=17896
and http://www.ufz.de/index.php?de=17896

Weissflog, L. N.F. Elanskii, K. Kotte, F. Keppler, A.
Pfennigsdorff, C.A. Lange, E. Putz, L.V. Lisitzina, 2009,
Late Permian Changes in Conditions of the Atmosphere and
Enviroments Caused by Halogenated Gases. Dokladi Earth
Sciences. vol. 424, no. 6, pp. 818-823.

http://www.springerlink.com/content/t8n5118h4w180566/?p=8383a07971444193bea480c152b84936&pi=25

Yours,

Paul H.

Origin of Sirente “crater” (sag) disputed

Paul bristolia at yahoo.com
Thu Mar 26 09:08:34 EDT 2009

An article in journal of Geophysical Research disputes
the origin of the what has been called the “Sirente crater”.

The paper discussing this theory is:

Speranza, F., I. Nicolosi, N. Ricchetti, G. Etiope, P. Rochette,
L. Sagnotti, R. De Ritis, and M. Chiappini (2009), The
“Sirente crater field,” Italy, revisited. Journal of Geophysical
Research. vol. 114, B03103, doi:10.1029/2008JB005759
http://www.agu.org/pubs/crossref/2009/2008JB005759.shtml

They concluded:

“Our data show that the Sirente crater and the minor
depressions are simply the results of human activity and
karstic processes, respectively.”

An article that discusses this paper is:

Bondre, N., 2009, Geomorphology: Crater or not? Nature
Geoscience. vol 2, no. 3, p. 166.

TOC at
http://www.nature.com/ngeo/journal/v2/n3/index.html

PDF file at
http://www.tulane.edu/~kmstraub/Publications/Abrams_09/News_and_Views_09.pdf

Yours,

Paul H.

Kennett Talk and NOVA special on Younger Dryas Impacts

Paul bristolia at yahoo.com
Wed Mar 25 09:50:45 EDT 2009


E.P. Grondine mentioned the below NOVA Special in his post,
“[meteorite-list] NOVA special on Holocene Start Impacts and AD”.

PBS Program to Feature Two UMaine Scientists, March 23, 2009
http://www.umaine.edu/news/view_release.php?x=1237809989

Dr. Kennett gave a talk, which included a lot of research that is either
being prepared for publication, been submitted for publication, and in
press. Dr. Kennett made a very convincing case that something unique,
extraordinary, and instantaneous occurred at the beginning of the
Younger Dryas about 12,900 B. calender years ago and could be an
event that was extraterrestrial in nature. His idea that it involved
multiple, simultaneous Tunguska-like events occurring across the
North American continent.

He also, discussed and showed pictures of the research on the
Greenland ice sheet, carried out by Paul Mayewski, and Andrei
Kurbatov. Outcropping along the edge of the Greenland Ice Sheet
is a well defined Younger Dryas bed, which consists of dark grey
dusty ice with clean, white Holocene ice above it and clean, white
terminal Pleistocene ice below it. They found the nannodiamonds
and other alleged impact indicators right at and only at the basal
contact of the Younger Dryas ice layer. They found exactly what
would be expected for an layer of meteoritic debris from Tunguska-
like events.

This is a show that you do not want to miss.

It is in the realm of possibility, that decade or so from now, Dr.
West, Dr. Kennett, and other members the YDB Group will likely
be known as the "Walter Alvarezes of the Quaternary.

I am now getting together with a couple of archaeologists to do
some “prospecting” for nannodiamonds and microspherules.

Some relevant publications:

Haynes, V. C., Jr., 2008, Younger Dryas “black mats” and the
Rancholabrean termination in North America. Proceedings of the
National Academy of Sciences. vol. 105 no. 18 6520-6525
http://www.pnas.org/content/105/18/6520.abstract

Did a Significant Cool Spell Mark the Demise of Megafauna?
http://uanews.org/node/19409

Kennett, J.D., J.P. Kennett, G.J. West, J.M. Erlandson, J.R.
Johnson, I.L. Hendy, A. West, B.J. Culleton, T.L. Jones and
Thomas W. Stafford Jr., 2008, Quaternary Science Reviews.
vol. 27, no. 27-28, pp. 2530-2545.
http://dx.doi.org/10.1016/j.quascirev.2008.09.006

Kennett, D.J., J. P. Kennett, A. West, C. Mercer, S. S. Que
Hee, and L. Bement, 2009, Nanodiamonds in the Younger Dryas
Boundary Sediment Layer. Science. vol. 323, no. 5910, p. 94.
http://www.sciencemag.org/cgi/content/abstract/323/5910/94

Best Regards,

Paul H

The terrestrial Permian-Triassic boundary event bed is a nonevent

Paul bristolia at yahoo.com
Tue Mar 17 13:18:58 EDT 2009

New paper about the Permian-Triassic boundary is South Africa
has been published in the March 2009 issue of “Geology”. It
argues that the so-called “event bed” that allegedly marks the
Permian-Triassic boundary neither marks it nor can be used to
interpreted paleoenvironmental changes that occurred during
the Permian-Triassic extinction event. The paper is:

Gastaldo, R.A., J. Neveling2, C.K. Clark, and S.S. Newbury, 2009,
The terrestrial Permian-Triassic boundary event bed is a nonevent
Geology. vol. 37, no. 3, pp. 199-202, doi:10.1130/G25255A.1

The abstract for Gastaldo, et al. (2009) can be found at:

http://geology.gsapubs.org/cgi/content/abstract/37/3/199

and the PDF file for it can be obtained from either:

http://www.colby.edu/~ragastal/RAG_reprints/RAG2009a.pdf

or http://www.colby.edu/~ragastal/Publications.htm

“ GSA Data Repository Item 2009056, The terrestrial Permian-Triassic
boundary event bed is a non-even” is downloadable from:

ftp://rock.geosociety.org/pub/reposit/2009/2009056.pdf

Yours,

Paul H.

Renewed Interest in Asteroid Defence

Paul
Fri Mar 13 16:32:33 EDT 2009

Near Miss Renews U.N. Interest in Asteroid Defence By Thalif Deen,
Inter Press Service, http://www.ipsnews.net/news.asp?idnews=46089

NEO News (03/12/09) UN Report on NEO Threat Mitigation
http://planetarydefense.blogspot.com/2009/03/neo-news-031209-un-report-on-neo-threat.html

NEO News (03/07/09) Newsworthy NEAs: 2009DD45 & 2008TN166
http://planetarydefense.blogspot.com/2009/03/neo-news-030709-newsworthy-neas.html

Surprise Asteroid Buzzed Earth Monday, National Geographic, March 2, 2009,
http://news.nationalgeographic.com/news/2009/03/090302-asteroid-earth.html

EDITORIAL COMMENT | Cosmic Near-miss, Times of India,
March 11, 2009
http://timesofindia.indiatimes.com/Opinion/EDITORIAL-COMMENT--Cosmic-Near-miss/articleshow/4253466.cms

Yours,

Paul H.

Recently Published Papers on Impact Structures and Impactites

Paul
Sun Feb 15 23:11:48 EST 2009

Dear Friends,

Below are some recent papers about impact structures and
alleged impactites that have appeared.

1. Schmieder, M., E. Buchner, and D. P. LeHeron, 2009, The Jebel
Hadid structure (Al Kufrah Basin ,SE Libya)—A possible impact
structure and potential hydrocarbon trap? Marine and Petroleum
Geology. vol 26. no. 3, pp. 310-318. doi:10.1016/j.marpetgeo.2008.04.003

http://dx.doi.org/10.1016/j.marpetgeo.2008.04.003

The Jebel Hadid structure is formed in the Nubian Sandstone and
located in southern Al Kufrah Basin. It is a 4.7 km circular
feature with a set of multiple concentric annular ridges. they
suggest "that the Jebel Hadid structure might represent an
eroded, complex impact structure' much like the Tin Bider
structure in Algeria. Its location is 20º 52' N and 22º 42' E).

2. Ghoneim, E. M., 2008, Ibn-Batutah: A possible simple impact
structure in southeastern Libya, a remote sensing study.
Geomorphology. vol. 103, no. 3, pp. 341-350.

The Ibn-Batutah feature is a circular structure centered on
21° 34′ 10″ N and 20° 50′ 15″ E and located in southeastern
Libya. It is formed in Nubian Sandstone.

http://dx.doi.org/10.1016/j.geomorph.2008.07.005
http://www.bu.edu/remotesensing/faculty/research/ghoneim/index.html

3. McCall, G. J. H., 2009, Half a century of progress in research
on terrestrial impact structures: A review. Earth-Science Reviews.
vol 92, no. 3-4, pp. 99-116.

http://dx.doi.org/10.1016/j.earscirev.2008.11.004

4. McCall, G. J. H., in press, The Carbonado diamond conundrum
Earth-Science Reviews, In Press, Accepted Manuscript, Available
online 13 February 2009. doi:10.1016/j.earscirev.2009.01.002

http://dx.doi.org/10.1016/j.earscirev.2009.01.002

"The reviewer presents the results of a literature search on the
enigmatic occurrences of carbonado; a form (but not the only
form) of polycrystalline diamond, which is mined for industrial
diamonds."

He hypothesizes that "carbonado does stem from terrestrial
eruptive processes" and concludes that much research remains
to be performed before any conclusions can be reached.

5. Schmieder, M., and E. Buchner, 2007, Short note: The Faya
basin (N Chad, Africa) – A possible impact structure? Journal
of African Earth Sciences. vol. 47, pp. 62–68.

The Faya basin is an almost circular structure, centered on
18º 10' N and 19º 34' E. It lies about 55 km ENE of the city
of Faya (Largeau) and has a diameter of about 2 km."

http://dx.doi.org/10.1016/j.jafrearsci.2006.11.004
http://adsabs.harvard.edu/abs/2007JAfES..47...62S

Yours,

Paul

Life forms May Have Evolved In Ancient Hot Springs On Mars

Paul
Thu Feb 12 15:12:21 EST 2009

Life forms May Have Evolved In Ancient Hot Springs On Mars
Science Daily, Feb. 12, 2009

http://www.sciencedaily.com/releases/2009/02/090212112829.htm

Evidence of Ancient Hot Springs on Mars Detailed in
Astrobiology Journal, Vicki Cohn, Mary Ann Liebert,
Inc. publishers

http://www.liebertpub.com/prdetails.aspx?pr_id=693

Allen C. C., and D. Z. Oehler, in press, A Case for
Ancient Springs in Arabia Terra, Mars. Astrobiology.

PDF file can be found at

http://www.liebertonline.com/doi/pdfplus/10.1089/ast.2008.0239

Yours,

Paul H.