Featured Research

from universities, journals, and other organizations

Scientist Uncovers Miscalculation In Geological Undersea Record

Date:
September 13, 2008
Source:
University of Miami Rosenstiel School of Marine & Atmospheric Science
Summary:
The precise timing of the origin of life on Earth and the changes in life during the past 4.5 billion years has been a subject of great controversy for the past century. The principal indicator of the amount of organic carbon produced by biological activity traditionally used is the ratio of the less abundant isotope of carbon, 13C, to the more abundant isotope, 12C. A new study challenges how geologists interpret variations in the 13C/12C ratio throughout Earth's history.

A new study examines changes in carbon isotope ratios over the past 10 million years at sites off the Bahamas (Atlantic Ocean), the Maldives (Indian Ocean), and Great Barrier Reef (Pacific Ocean).
Credit: NASA

The precise timing of the origin of life on Earth and the changes in life during the past 4.5 billion years has been a subject of great controversy for the past century.

The principal indicator of the amount of organic carbon produced by biological activity traditionally used is the ratio of the less abundant isotope of carbon, 13C, to the more abundant isotope, 12C. As plants preferentially incorporate 12C, during periods of high production of organic material the 13C/12C ratio of carbonate material becomes elevated. Using this principle, the history of organic material has been interpreted by geologists using the 13C/12C ratio of carbonates and organics, wherever these materials can be sampled and dated.

While this idea appears to be sound over the last 150 million years or so, prior to this time there are no open oceanic sediment records which record the 13C/12C ratio, and therefore, geologists are forced to use materials associated with carbonate platforms or epicontinental seas.

In order to test whether platform-associated sediments are related to the global carbon cycle, a paper by University of Miami Professor Dr. Peter K. Swart appears in the Proceedings of the National Academy of Sciences. This paper examines changes over the past 10 million years at sites off the Bahamas (Atlantic Ocean), the Maldives (Indian Ocean), and Great Barrier Reef (Pacific Ocean). The variations in the 13C/12C ratio are synchronous at all of the sites studied, but are unrelated to the global change in the 13C/12C ratio.

It appears that records related to carbonate platforms which are often used throughout the early history of the Earth are not good recorders of the 13C/12C ratio in the open oceans. Hence, the work presented suggests that assumptions made previously about changes in the 13C/12C ratios of carbonate sediments in the geological record are incorrect.

"This study is a major step in terms of rethinking how geologists interpret variations in the 13C/12C ratio throughout Earth's history. If the approach does not work over the past 10 million years, then why would it work during older time periods?" said Swart. "As a consequence of our findings, changes in 13C/12C records need to be reevaluated, conclusions regarding changes in the reservoirs of carbon will have to be reassessed, and some of the widely-held ideas regarding the elevation of CO2 during specific periods of the Earth's geological history will have to be adjusted."

The study is funded by the National Science Foundation and the Comparative Sedimentology Laboratory at the University of Miami.


Story Source:

The above story is based on materials provided by University of Miami Rosenstiel School of Marine & Atmospheric Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Peter K. Swart. Global synchronous changes in the carbon isotopic composition of carbonate sediments unrelated to changes in the global carbon cycle. Proceedings of the National Academy of Sciences, 2008; DOI: 10.1073/pnas.0802841105

Cite This Page:

University of Miami Rosenstiel School of Marine & Atmospheric Science. "Scientist Uncovers Miscalculation In Geological Undersea Record." ScienceDaily. ScienceDaily, 13 September 2008. <www.sciencedaily.com/releases/2008/09/080910104202.htm>.
University of Miami Rosenstiel School of Marine & Atmospheric Science. (2008, September 13). Scientist Uncovers Miscalculation In Geological Undersea Record. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2008/09/080910104202.htm
University of Miami Rosenstiel School of Marine & Atmospheric Science. "Scientist Uncovers Miscalculation In Geological Undersea Record." ScienceDaily. www.sciencedaily.com/releases/2008/09/080910104202.htm (accessed August 23, 2014).

Share This




More Earth & Climate News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Airlines on Iceland Volcano Alert

Airlines on Iceland Volcano Alert

Reuters - Business Video Online (Aug. 22, 2014) Iceland evacuates an area north of the country's Bardarbunga volcano, as the country's civil protection agency says it cannot rule out an eruption. Authorities have already warned airlines. As Joel Flynn reports, ash from the eruption of the Eyjafjallajokull volcano in 2010 shut down much of Europe's airspace for six days. Video provided by Reuters
Powered by NewsLook.com
Endangered Red Wolves Face Uncertain Future

Endangered Red Wolves Face Uncertain Future

AP (Aug. 22, 2014) A federal judge temporarily banned coyote hunting to save endangered red wolves, but local hunters say that the wolf preservation program does more harm than good. Meanwhile federal officials are reviewing its wolf program in North Carolina. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Coal Gas Boom in China Holds Climate Risks

Coal Gas Boom in China Holds Climate Risks

AP (Aug. 22, 2014) China's energy revolution could do more harm than good for the environment, despite the country's commitment to reducing pollution and curbing its carbon emissions. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Microbrewery Chooses Special Can for Its Beer

Microbrewery Chooses Special Can for Its Beer

AP (Aug. 22, 2014) Aluminum giant, Novelis, has partnered with Red Hare Brewing Company to introduce the first certified high-content recycled beverage can. (Aug. 22) 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