It is interesting seeing the difference...

[stellar_muddle]

basal_surge was going to get the points of posting this one first, but since he has been too slack...
"Crispy Mammoths!!"
Spot the contrast between NZ Herald article on the subject

Ancient comet explosion left trail of destruction
5:00AM Monday May 21, 2007 (NZ Herald)

LONDON - Evidence suggesting a comet exploded over the Earth nearly 13,000 years ago, creating a hail of fireballs that set fire to most of the Northern Hemisphere, will be outlined by scientists this week.

Stone Age cultures were destroyed and populations of mammoths and other large land animals were wiped out. The blast also caused a major bout of climatic cooling that lasted 1000 years and seriously disrupted the development of the early human civilisations emerging in Europe and Asia.

"This comet set off a shock wave that changed Earth profoundly," said Arizona geophysicist Allen West.

"It was about 2km-3km in diameter and broke up just before impact, setting off a series of explosions, each the equivalent of an atomic bomb blast.

"The result would have been hell on Earth. Most of the Northern Hemisphere would have been left on fire."

The theory is to be outlined at the American Geophysical Union meeting in Acapulco, Mexico.

A group of US scientists including West will report that they have found a layer of microscopic diamonds at 26 different sites in Europe, Canada and North America. They say these are the remains of the giant carbon-rich comet that crashed 12,900 years ago.

The huge pressures and heat triggered by the fragments crashing to Earth turned the comet's carbon into diamond dust.

"The shock waves and the heat would have been tremendous," said West. "It would have set fire to animals' fur and to human clothing. The searing heat would have also set fire to the grasslands of the Northern Hemisphere.

"Great grazing animals like the mammoth that had survived the original blast would have died later in their thousands from starvation. Only animals, including humans, that had a wide range of food would have survived the aftermath."

The scientists point out that archaeological evidence shows that early Stone Age cultures clearly suffered serious setbacks at this time.

In particular, American Stone Age hunters, descendants of the hunter-gatherers who had migrated to the continent from Asia, vanished.

Their disappearance has been a cause of intense debate, with climate change being put forward as an explanation.

Now there is a new idea: the first Americans were killed by a comet, as were countless others.

- OBSERVER

and
Abstract from the Acapulco American Geophysics Union conference:

Evidence for a Massive Extraterrestrial Airburst over North America 12.9 ka Ago

Richard B. Firestone 1 (*contact details removed*)
Allen West 2 (*contact details removed*)
Zsolt Revay 3
Tamas Belgya 3
Allan Smith 1
Shane S. Que Hee 4

1 Lawrence Berkeley National Laboratory, Berkeley, CA 94720, Berkeley, CA 94720, United States
2 GeoScience Consulting, P.O.Box 1636, Dewey, AZ 86327, United States
3 Department of Nuclear Research, Institute of Isotopes, H-1525 Budapest, Hungary, Budapest H-1525, Hungary
4 Department of Environmental Health Sciences, University of California, Los Angeles CA 90095, Los Angeles, CA 90095, United States

A carbon-rich black layer commonly referred to as a black mat, with a basal age of approximately 12.9 ka, has been identified at over 50 sites across North America [1]. The age of the base of the black mat coincides with the abrupt onset of Younger Dryas (YD) cooling and megafaunal extinctions in North America. In situ bones of extinct mammals, including mammoths, mastodons, ground sloths, horses, camels, many smaller mammals and birds, and Clovis tool assemblages occur below the black mat but not within or above it. In this paper, we provide evidence for an ejecta layer at the base of the black mat from an extraterrestrial impact event 12.9 ka ago. We have investigated nine terminal Clovis-age sites in North America and a comparable site in Lommel, Belgium that are all marked by a thin, discrete layer containing varying peak abundances of (1) magnetic grains/microspherules containing iridium concentrations up to 117 ppb, (2) charcoal, (3) soot, (4) vesicular carbon spherules, (5) glass-like carbon, and (6) fullerenes enriched in 3He. This layer also extends throughout the rims of at least fifteen Carolina Bays, unique, elliptical, oriented lakes and wetlands scattered across the Atlantic Coastal Plain whose major axes point towards the Great Lakes and Canada. Microspherules, highly enriched in titanium, were found only in or near the YD boundary (YDB) layer with greatest deposition rates (35 per cm2) occurring near the Great Lakes. Magnetic grains also peak in the YDB with maximum deposition near the Great Lakes (30 mg/cm2). Magnetic grains near the Great Lakes are enriched in magnetite (4 mg/cm2) and silicates (23 mg/cm2) but contain less ilmenite/rutile (1 mg/cm2) than distant sites where ilmentite/rutile deposition ranges up to 18 mg/cm2. Analysis of the ilmenite/rutile-rich magnetic grains and microspherules indicates that they contain
considerable water, up to 28 at.\% hydrogen, and have TiO2/FeO, TiO2/Zr, Al2O3/FeO+MgO, CaO/Al2O3, REE/chondrite, K/Th, FeO/MnO ratios and SiO2, Na2O, K2O, Cr2O3, Ni, Co, Ir, Th, U, and other trace element abundances that are inconsistent with all terrestrial and extraterrestrial sources except for Lunar Procellarum KREEP terrain (PKT). We propose that the YDB layer is the ejecta layer from an airburst over the Laurentide Ice Sheet that deposited local, low-speed terrestrial material near the airburst site and KREEP-like, high-speed projectile material farther away, leaving little or no permanent crater. The associated blast wave and thermal pulse would have contributed to the megafaunal extinctions and destabilized the
Laurentide Ice Sheet, loading the atmosphere with dust, soot, NOx, and water vapor and triggered the YD cooling.
[1] Haynes, C. V., Jr. in Murray Springs: a Clovis site with multiple activity areas in the San Pedro Valley, Arizona. C. V. Haynes, Jr. and Bruce B. Huckell, eds. Tucson:
Univ. of Arizona Press, in press, 2007.


More info on the impact from http://georgehoward.net/Carolina_bay_abstracts.htm from I think one of the authors, so I am not certain of the impartiality. Be interesting to see how is stands up to peer review.