Featured Research

from universities, journals, and other organizations

Where have all the craters gone?

Date:
May 27, 2014
Source:
Geological Society of America
Summary:
Impact craters reveal one of the most spectacular geologic process known to human beings. During the past 3.5 billion years, it is estimated that more than 80 bodies, larger than the dinosaur-killing asteroid that struck the Yucatan Peninsula 66 million years ago, have bombarded Earth. However, tectonic processes, weathering, and burial quickly obscure or destroy craters. If Earth weren't so dynamic, its surface would be heavily cratered like the Moon or Mercury.

Ouarkziz Impact Crater.
Credit: Image courtesy NASA

Impact craters reveal one of the most spectacular geologic process known to human beings. During the past 3.5 billion years, it is estimated that more than 80 bodies, larger than the dinosaur-killing asteroid that struck the Yucatan Peninsula 66 million years ago, have bombarded Earth. However, tectonic processes, weathering, and burial quickly obscure or destroy craters. For example, if Earth weren't so dynamic, its surface would be heavily cratered like the Moon or Mercury.

Work by B.C. Johnson and T.J. Bowling predicts that only about four of the craters produced by these impacts could persist until today, and geologists have already found three such craters (larger than 170 km in diameter). Their study, published online for Geology on 22 May 2014, indicates that craters on Earth cannot be used to understand Earth's bombardment history.

Johnson and Bowling write, however, that layers of molten rock blasted out early in the impact process may act as better records of impacts -- even after the active Earth has destroyed the source craters. The authors suggest that searches for these impact ejecta layers will be more fruitful for determining how many times Earth was hit by big asteroids than searches for large craters.


Story Source:

The above story is based on materials provided by Geological Society of America. Note: Materials may be edited for content and length.


Journal Reference:

  1. B. C. Johnson, T. J. Bowling. Where have all the craters gone? Earth's bombardment history and the expected terrestrial cratering record. Geology, 2014; DOI: 10.1130/G35754.1

Cite This Page:

Geological Society of America. "Where have all the craters gone?." ScienceDaily. ScienceDaily, 27 May 2014. <www.sciencedaily.com/releases/2014/05/140527154715.htm>.
Geological Society of America. (2014, May 27). Where have all the craters gone?. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2014/05/140527154715.htm
Geological Society of America. "Where have all the craters gone?." ScienceDaily. www.sciencedaily.com/releases/2014/05/140527154715.htm (accessed July 30, 2014).

Share This




More Earth & Climate News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins