Including Original "Paul H. Letters" Copyright © 1996-2017 Paul V. Heinrich - All rights reserved.



Saturday, 22 December 2007

Coal Methane Contributed Late Permian Extinctions ????

Coal Methane Contributed Late Permian Extinctions ????

Paul bristolia at yahoo.com
Fri Dec 21 16:23:22 EST 2007

Dear friends,

There is an interesting paper about how coal methane
might have contributed to Late Permian extinctions.

It is:

Retallack, G. J., and A. H. Jahren. 2007, Methane Release
from Igneous Intrusion of Coal during Late Permian
Extinction Events. The Journal of Geology. vol. 116, pp. 1–20

http://www.journals.uchicago.edu/doi/abs/10.1086/524120

In part the abstract read:

“Unusually large and locally variable carbon isotope excursions
coincident with mass extinctions at the end of the Permian
Period (253 Ma) and Guadalupian Epoch (260 Ma) can be
attributed to methane outbursts to the atmosphere. .... On
paleogeographic maps, the most marked carbon isotope
excursions form linear arrays back to plausible methane
sources: end-Permian Siberian Traps and Longwood-Bluff
intrusions of New Zealand and end-Guadalupian Emeishan
Traps of China. Intrusion of coal seams by feeder dikes to
flood basalts could create successive thermogenic methane
outbursts of the observed timing and magnitude, ...
Methane released by fracturing and heating of coal during
intrusion of large igneous provinces may have been a
planetary hazard comparable with bolide impact.”

This paper concluded:

“Addition of the end-Guadalupian case to the better known
end-Permian, end-Triassic, and end-Cretaceous cases
makes coincidence less likely, and copious generation of
methane by intrusion of coals supplies ample killing power.
Like meteorite and comet impacts, thermogenic methane
outbursts may have been significant hazards to life on Earth.”

Yours,

Paul H.

Friday, 14 December 2007

Meteorite articles in "Comptes Rendus Geosciences"

Meteorite articles in "Comptes Rendus Geosciences"

Paul bristolia at yahoo.com
Thu Dec 13 09:26:18 EST 2007

Volume 339, No. 14-15 (November 2007), issue of Comptes
Rendus Geosciences has a few articles about "Formation
du système solaire : approche cosmochimique dans le c
onteste astrophysique. They include:

1. Short-lived radioactive nuclides in meteorites and early
solar system processes by Marc Chaussidon and Matthieu
Gounelle.

2. The insoluble organic matter in carbonaceous chondrites:
Chemical structure, isotopic composition and origin by
Laurent Remusat, François Robert and Sylvie Derenne

and 3. Impacts in the primordial history of terrestrial planets
by Alessandro Morbidelli

Yours,

Paul H.

Arctic Impact Crater Lake Reveals Interglacial Climate

Arctic Impact Crater Lake Reveals Interglacial Climate

Paul bristolia at yahoo.com
Thu Dec 13 09:21:21 EST 2007

Arctic Impact Crater Lake Reveals Interglacial
Cycles in Sediments Univerity of Arkansas,
December 11, 2007

http://dailyheadlines.uark.edu/11974.htm

Pingualuit Crater Lake Project

http://www.cen.ulaval.ca/pingualuit/index.html

Yours

Paul H.

Thursday, 13 December 2007

Evidence Against Permian-Triassic Asteroid Impact Published

Evidence Against Permian-Triassic Asteroid Impact Published

Paul bristolia at yahoo.com
Wed Dec 12 16:21:26 EST 2007

In “December Media Highlights: Geology and GSA Today” at:
http://www.geosociety.org/news/pr/07-68.htm, there is:

Xie, S., R. D. Pancost, J. Huang, P. B. Wignall, J.
Yu, X. Tang, L. Chen, X. Huang, and X. Lai, 2007,
Changes in the global carbon cycle occurred as two
episodes during the Permian-Triassic crisis. Vol. 35,
no. 12, pp. 1083-1086.

http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FG24224A.1

The press release stated:

“Earth witnessed its most severe mass extinction 250
million years ago. This extinction has been thought
to be abrupt and probably caused by an extraterrestrial
impact. However, Xie et al. present several lines of
geochemical evidence from a South China section (an
optimal section to study the biotic crisis) that
indicates a two-episodic global change in association
with the ecological crisis. The global carbon cycle,
the enhanced terrestrial weathering, the marine
photic zone euxinia, the faunal mass extinction,
and the cyanobacterial expansion all occurred as two
episodes, showing a close coupling among the ocean,
the atmosphere, and the land system at that time. In
particular, Xie et al. found that the first episode
occurred before the presumed bolide impact. The
temporal sequence of these two events suggests that
the biotic crisis was a consequence of prolonged and
episodic changes in the marine and continental
systems, and argues against an extraterrestrial
impact as the main cause.”

Yours,

Paul H.

Crow Creek Member of Pierre Shale is Impact Tsunami Generated

Crow Creek Member of Pierre Shale is Impact Tsunami Generated

Paul bristolia at yahoo.com
Wed Dec 12 16:19:38 EST 2007

In “December Media Highlights: Geology and GSA Today” at:
http://www.geosociety.org/news/pr/07-68.htm , there is:

Weber, R. D., and D. K. Watkins, 2007, Evidence from
the Crow Creek Member (Pierre Shale) for an impact-
induced resuspension event in the late Cretaceous
Western Interior Seaway. . Vol. 35, no. 12,
pp. 1119-1122.

http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FG24209A.1

The press release stated:

The Crow Creek Member, a unique rock unit in the Upper
Cretaceous Pierre Shale in South Dakota and Nebraska,
has been thought to represent sea-level rise along
the eastern margin of the Western Interior Seaway.
However, Weber et al. show that the presence of impact
ejecta from the Manson Impact Structure, found within
the Member, suggests an impact-induced genesis.
Current investigation of a reworked nannofossil
assemblage occurring within the Crow Creek Member is
consistent with an origin involving gravitational
settling rather than sea-level rise. Additionally,
the reworked assemblage decreases in abundance with
increased distances from the Manson Impact Structure.
These observations support the hypothesis that Manson
Impact may have caused a re-suspension event in the
Western Interior Seaway, resulting in Crow Creek
deposition.”

Yours,

Paul H.

AGU Paper Claims Meteorites Blasted Mammoths

AGU Paper Claims Meteorites Blasted Mammoths

Paul bristolia at yahoo.com
Wed Dec 12 09:56:40 EST 2007

Great beasts peppered from space
By Jonathan Amos, BBC News

http://news.bbc.co.uk/1/hi/sci/tech/7130014.stm

“Startling evidence has been found which shows
mammoth and other great beasts from the last
ice age were blasted with material that came
from space.”

+++++

Mammoth tusks show up meteorite shower: Fossils
could provide a new gold mine for micrometeorite
hunters by Rex Dalton, Nature News

http://www.nature.com/news/2007/071212/full/news.2007.372.html

+++++

Proof great beasts were blasted from space By
Laura Clout, T he Telegraph, Decemebr 12, 2007

http://www.telegraph.co.uk/earth/main.jhtml?view=DETAILS&grid=&xml=/earth/2007/12/12/scidino212.xml

Yours,

Paul