Text Version
RSS Feeds
Newsletter
Home Forum Photos Features Newsletter Archive Employment
About US Help Site Map
SEARCH   About US FAQ Site Map Site News
  SERVICES
  -Text Version
  -RSS Feeds
  -Newsletter
  -News Archive
  -Give us feedback
  -Voices of Readers
  -Online community
  -China Biz info
  What's new
 -
 -
Dinosaur-killing asteroid covered Earth with beads
+ -
20:18, May 08, 2008

 Related News
 Skeleton of dinosaur to be sold
 China Exclusive: Giant step ahead as experts find big cluster of dinosaur footprints
 Dinosaurs to get new home in Heyuan
 New dinosaur species identified in E China
 New dinosaur species identified in E China
 Comment  Tell A Friend
 Print Format  Save Article
The dinosaur-killing asteroid that impacted the Yucatan Peninsula 65 million years ago did so with such force it pulverized Earth's crust, creating a veil of airborne carbon beads that blanketed the planet, a new study reveals.

Spanning about 124 miles (200 kilometers), the giant indentation left by the asteroid impact continues to be a treasure trove of clues for scientists piecing together the wipe-out of 70 percent of life on Earth, including non-avian dinosaurs. Called the Chicxulub Crater, this CSI-site is located just west of Mexico's Yucatan Peninsula.

Geologists generally agree an asteroid slammed into Earth at the end of the Cretaceous period; that the catastrophic impact sent molten rock and super-hot ash airborne; and that as the molten material fell from the sky, it ignited flammable flora, sparking forest fires.

More perplexing has been the formation of carbon particles called cenospheres hiding out in rocks of the Chicxulub Crater and other sites. One idea was that the carbon beads were charred remnants formed as a result of the plant-burning.

That seemed plausible since, until now, such carbon beads were associated only with modern power plants, and scientists thought intense burning of coal and crude oil generated the structures. Power plants didn't exist 65 million years ago, and even heat produced by pressure from layers of earth deposited atop the dino fossils would not have been sufficient to form the beads.

However, flames were not needed, say the current researchers, who find besides that the combustion of plants wouldn't produce such paleo-beads. Rather than a flammable origin, the carbon beads could have formed from the violent pulverization of the Earth's carbon-rich crust.

Their counter-view, detailed in this month's issue of the journal Geology, comes from analyses of cenospheres within rock samples collected at oceanic and inland locations around the world.

"Carbon embedded in the rocks was vaporized by the impact, eventually forming new carbon structures in the atmosphere," said researcher Simon Brassell, a geologist at Indiana University, Bloomington.

Source: Xinhua/Agencies



  Your Message:   Most Commented:
Chinese netizen discussion of"boycott on French goods"
Miley Cyrus' sexy photos cause controversy
What is Nancy Pelosi really up to?
Dalai's brag about "peace", "non-violence" is nothing but lie
FM: China strongly denounces CNN host's insulting words

|About Peopledaily.com.cn | Advertise on site | Contact us | Site map | Job offer|
Copyright by People's Daily Online, All Rights Reserved

http://english.people.com.cn/90001/90781/90879/6407175.pdf