[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Precisely Dating The KT Boundary

http://www.sciencedaily.com/releases/2006/08/060822172243.htm August 23, 2006

The mass extinction of dinosaurs occurred about 66 million years ago, at the end of the Cretaceous Period (K) and the beginning of the Tertiary Period, known as the K-T boundary. A massive asteroid slammed into what is now the Gulf of Mexico about that time.

"About" is the key word here. The correlation is close, but not close enough for Samuel A. Bowring, a professor of geology in MIT's Department of Earth, Atmospheric and Planetary Sciences.

"With the K-T boundary and the death of the dinosaurs, everyone is happy with it being caused by an impact. To me, that's a reason not to be happy," said Bowring.

Bowring thinks there is a correlation between the two events. But he firmly believes that it may be possible to more precisely date the sequence of events before, during and after the extinction.
In 2003 Bowring launched the Earthtime initiative to bring together scientists from all over the world to work together to calibrate and sequence Earth history through the integration of high-precision geochronology and quantitative chronostratigraphy.

Now, Earthtime (http://www.earth-time.org) has more than 200 members, hailing from a variety of disciplines. ...

Earthtime's official goal is to bring dating accuracy to better than 0.1 percent. That means in dating a 250-million-year-old fossil, results would be plus or minus 250,000 years. Bowring thinks it is possible to improve precision to 0.05 percent.
"We are working on the age of the K-T boundary right now using zircon and we think we can constrain it to within about 50,000 years," Bowring said.