Thursday, November 19, 1998
Dinosaurs’ end less mysterious due to recent UCLA discovery
RESEARCH: Fragment of 65-million-year-old asteroid found by
Kyte
By Andy Shah
Daily Bruin Contributor
The theory that dinosaurs vanished from the planet because of a
huge asteroid impact just received more support from a discovery by
Frank Kyte, a UCLA geophysicist and professor of oceanography.
Kyte discovered what he says is the first known fragment of an
asteroid that hit the earth 65 million years ago, possibly
eliminating 70 percent of all plant and animal species, including
the dinosaurs.
"We can now add information to the debate of whether it was a
comet or an asteroid that caused the impact," he said. "Comets are
more fluffy, whereas my sample is more compact, so it’s probably an
asteroid."
Kyte said the fragment he found has high concentrations of
iridium, which is usually found in meteorites.
Kyte pulled the fragment from the K/T layer of the Pacific
Ocean, which scientists believe is a layer of debris that settled
back to Earth after being blown away by the meteor.
"The K/T layer has ejecta from the impact, such as high levels
of iridium," he said.
Kyte said he also found samples of quartz granules, which show
signs of being impacted by the asteroid.
The fragment also contains large amounts of iron, nickel and
chromium.
But he added that he hasn’t proven if his sample is from the
actual asteroid that wiped out the dinosaurs.
"There’s no question that this fragment is from an asteroid," he
said. "But it’s open to debate if it’s from the actual asteroid
that killed the dinosaurs."
Kyte said he isn’t phased by this discovery.
"It’s pretty cool, but I’m not that excitable," he said. "I’ve
done stuff before which I thought was more exciting than this."
Kyte first presented the fragment at a NASA meeting three years
ago, and used electron microscopes to examine whether it came from
an asteroid.
He published his findings recently.
Other scientists have found fragments from the K/T layer that
might have been part of the asteroid, but they were too small to
analyze.
"The K/T asteroid was something like 6 miles across, and it got
blasted into pieces that would fit on the head of a pin," said Jeff
Pleschia, a crater specialist with the U.S. Geological Service in
Flagstaff, Arizona.
Kyte has been researching the K/T layer for 18 years.
"I’ve worked with the layer’s sediments and spherules for
years," he said. "It’s just really interesting stuff."
Kyte said he will continue to work with impact deposits. He said
he is currently analyzing some meteoric deposits he found in the
ocean near southern Chile.
"Those fragments are bigger, but they’re younger," he said.
Written with Daily Bruin wire reports
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