This is of course the Pleistocene nonconformity that I first wrote up
in 2005 and posted here in 2007. I predicted that we would prove a
targetedv comet impact into the Northern Ice sheet. The hard
evidence that continues to be gathered continues to conform to my
conjecture. No one has completely woken up to the targeted nature of
this event yet and may well remain unprovable unless we locate the
center of the impact itself.
I also need someone to do an isotope analysis of the carbon itself.
This carbon was integral to the comet itself and came in from space.
Thus it must be different than carbon formed by forests burning after
the shaockwave passed through.
The actual impact would have changed temproraily the rotational speed
of the crust and induced a southward shift of the pole that likely
was partially powered by internal dynamo as well as the blunt impact.
This will be a difficult simulation to pull off that demands plenty
of conventional mechanics. That it could be done in terms of our own
knowledge is pretty certain although the finesse would be difficult.
Study examines
13,000-year-old nanodiamonds from multiple locations across three
continents
Aug 27, 2014 by Julie
Cohen
A transmission
electron microscopy image of carbon spherules from the Younger Dryas
Boundary 30 cm below the surface in Gainey, Michigan. Credit: UCSB
Most of North
America's megafauna—mastodons, short-faced bears, giant ground
sloths, saber-toothed cats and American camels and horses—disappeared
close to 13,000 years ago at the end of the Pleistocene period. The
cause of this massive extinction has long been debated by scientists
who, until recently, could only speculate as to why.
A group of scientists,
including UC Santa Barbara's James Kennett, professor emeritus in the
Department of Earth Science, posited that a comet collision with
Earth played a major role in the extinction. Their hypothesis
suggests that a cosmic-impact event precipitated the Younger Dryas
period of global cooling close to 12,800 years ago. This cosmic
impact caused abrupt environmental stress and degradation that
contributed to the extinction of most large animal species then
inhabiting the Americas. According to Kennett, the catastrophic
impact and the subsequent climate change also led to the
disappearance of the prehistoric Clovis culture, known for its big
game hunting, and to human population decline.
In a new study
published this week in the Journal of Geology, Kennett and an
international group of scientists have focused on the character and
distribution of nanodiamonds, one type of material produced during
such an extraterrestrial collision. The researchers found an
abundance of these tiny diamonds distributed over 50 million square
kilometers across the Northern Hemisphere at the Younger Dryas
boundary (YDB). This thin, carbon-rich layer is often
visible as a thin black line a few meters below the surface.
Kennett and
investigators from 21 universities in six countries investigated
nanodiamonds at 32 sites in 11 countries across North America, Europe
and the Middle East. Two of the sites are just across the Santa
Barbara Channel from UCSB: one at Arlington Canyon on Santa Rosa
Island, the other at Daisy Cave on San Miguel Island.
###
The solid line defines
the current known limits of the Younger Dryas Boundary field of
cosmic-impact proxies, spanning 50 million square kilometers. Credit:
UCSB
"We conclusively
have identified a thin layer over three continents, particularly in
North America and Western Europe, that contain a rich assemblage of
nanodiamonds, the production of which can be explained only by cosmic
impact," Kennett said. "We have also found YDB
glassy and metallic materials formed at temperatures in excess of
2200 degrees Celsius, which could not have resulted from
wildfires, volcanism or meteoritic flux, but only from cosmic
impact."
The team found that
the YDB layer also contained larger than normal amounts of cosmic
impact spherules, high-temperature melt-glass, grapelike soot
clusters, charcoal, carbon spherules, osmium, platinum and other
materials. But in this paper the researchers focused their
multi-analytical approach exclusively on nanodiamonds, which were
found in several forms, including cubic (the form of diamonds used in
jewelry) and hexagonal crystals.
"Different types of diamonds are found in the YDB assemblages
because they are produced as a result of large variations in
temperature, pressure and oxygen levels associated with the chaos of
an impact," Kennett explained. "These are exotic conditions
that came together to produce the diamonds from terrestrial carbon;
the diamonds did not arrive with the incoming meteorite or comet."
James P. Kennett,
professor emeritus in UCSB's Department of Earth Science. Credit:
Sonia Fernandez
Based on multiple
analytical procedures, the researchers determined that the majority
of the materials in the YDB samples are nanodiamonds and not some
other kinds of minerals. The analysis showed that the nanodiamonds
consistently occur in the YDB layer over broad areas.
"There
is no known limit to the YDB strewnfield which currently covers more
than 10 percent of the planet, indicating that the YDB event was a
major cosmic impact," Kennett said. "The
nanodiamond datum recognized in this study gives scientists a
snapshot of a moment in time called an isochron."
To date, scientists
know of only two layers in which more than one identification of
nanodiamonds has been found: the YDB 12,800 years ago and the
well-known Cretaceous-Tertiary boundary 65 million years ago, which
is marked by the mass extinction of the dinosaurs, ammonites and many
other groups.
"The evidence
we present settles the debate about the existence of abundant YDB
nanodiamonds," Kennett said. "Our hypothesis challenges
some existing paradigms within several disciplines, including impact
dynamics, archaeology, paleontology and
paleoceanography/paleoclimatology, all affected by this relatively
recent cosmic impact."
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