Thursday, September 24, 2009

New Starting Date For Quaternary


Doom Patrol © DC Comics
Controversy over when exactly the Quaternary Period began has raged for decades, with attempts in 1948 and 1983 to define the era. In 1983 the boundary was fixed at 1.8 million years, a decision which sparked argument within the earth science community as this point was not a 'natural boundary' and had no particular geological significance.

For practical reasons such boundaries should ideally be made as easy as possible to identify all around the world. The new boundary of 2.6 million years is just that," concluded Gibbard, "hence we are delighted at finally achieving our goal of removing the boundary to this earlier point."

The decision has been made by the International Commission on Stratigraphy (ICS), the authority for geological science which has acted to end decades of controversy by formally declaring when the Quaternary Period, which covers both the ice age and moment early man first started to use tools, began.

"It has long been agreed that the boundary of the Quaternary Period should be placed at the first sign of global climate cooling," said Professor Philip Gibbard. "What we have achieved is the definition of the boundary of the Quaternary to an internationally recognised and fixed point that represents a natural event, the beginning of the ice ages on a global scale." link