Six North American sites hold 12,900-year-old nanodiamond-rich soil

Jan 01, 2009

Abundant tiny particles of diamond dust exist in sediments dating to 12,900 years ago at six North American sites, adding strong evidence for Earth's impact with a rare swarm of carbon-and-water-rich comets or carbonaceous chondrites, reports a nine-member scientific team.

These nanodiamonds, which are produced under high-temperature, high-pressure conditions created by cosmic impacts and have been found in meteorites, are concentrated in similarly aged sediments at Murray Springs, Ariz., Bull Creek, Okla., Gainey, Mich., and Topper, S.C., as well as Lake Hind, Manitoba, and Chobot, Alberta, in Canada. Nanodiamonds can be produced on Earth, but only through high-explosive detonations or chemical vaporization.

Last year a 26-member team from 16 institutions proposed that a cosmic impact event, possibly by multiple airbursts of comets, set off a 1,300-year-long cold spell known as the Younger Dryas, fragmented the prehistoric Clovis culture and led to the extinction of a large range of animals, including mammoths, across North America. The team's paper was published in the Oct. 9, 2007, issue of the Proceedings of the National Academy of Sciences.

Now, reporting in the Jan. 2 issue of the journal Science, a team led by the University of Oregon's Douglas J. Kennett, a member of the original research team, report finding billions of nanometer-sized diamonds concentrated in sediments -- weighing from about 10 to 2,700 parts per billion -- in the six locations during digs funded by the National Science Foundation.

"The nanodiamonds that we found at all six locations exist only in sediments associated with the Younger Dryas Boundary layers, not above it or below it," said Kennett, a UO archaeologist. "These discoveries provide strong evidence for a cosmic impact event at approximately 12,900 years ago that would have had enormous environmental consequences for plants, animals and humans across North America."

The Clovis culture of hunters and gatherers was named after hunting tools referred to as Clovis points, first discovered in a mammoth's skeleton in 1926 near Clovis, N.M. Clovis sites later were identified across the United States, Mexico and Central America. Clovis people possibly entered North America across a land bridge from Siberia. The peak of the Clovis era is generally considered to have run from 13,200 to 12,900 years ago. One of the diamond-rich sediment layers reported sits directly on top of Clovis materials at the Murray Springs site.

News release on the 2007 paper is available here, with link to a copy of that paper.)

Source: University of Oregon

Explore further: Wrapping carbon nanotubes in polymers enhances their performance

Related Stories

Humans erode soil 100 times faster than nature

Jan 07, 2015

A new study shows that removing native forest and starting intensive agriculture can accelerate erosion so dramatically that in a few decades as much soil is lost as would naturally occur over thousands of ...

Geologists discover ancient buried canyon in South Tibet

Nov 20, 2014

A team of researchers from Caltech and the China Earthquake Administration has discovered an ancient, deep canyon buried along the Yarlung Tsangpo River in south Tibet, north of the eastern end of the Himalayas. ...

There's something ancient in the icebox

Apr 17, 2014

Glaciers are commonly thought to work like a belt sander. As they move over the land they scrape off everything—vegetation, soil, and even the top layer of bedrock. So scientists were greatly surprised ...

Recommended for you

Natural nanocrystals shown to strengthen concrete

6 hours ago

Cellulose nanocrystals derived from industrial byproducts have been shown to increase the strength of concrete, representing a potential renewable additive to improve the ubiquitous construction material.

From tobacco to cyberwood

Mar 30, 2015

Swiss scientists from ETH Zurich have developed a thermometer that is at least 100 times more sensitive than previous temperature sensors. It consists of a bio-synthetic hybrid material of tobacco cells and nanotubes.

'Atomic chicken-wire' is key to faster DNA sequencing

Mar 30, 2015

An unusual and very exciting form of carbon - that can be created by drawing on paper- looks to hold the key to real-time, high throughput DNA sequencing, a technique that would revolutionise medical research ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

WolfAtTheDoor
5 / 5 (1) Jan 02, 2009
Great, I can hear my wife now... "I want some jewelry for Christmas, and none of that 'nanodiamond' B.S. that you usually get me!"

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.