Early oceans more temperate than thought

STANFORD, Calif., Nov. 17 (UPI) -- U.S. scientists say the scalding-hot sea that many of us were taught covered the early Earth might, in fact, never have existed.

Stanford University researchers who analyzed isotope ratios in 3.4 billion-year-old ocean floor rocks say their findings suggest the early ocean was much more temperate and spread across the globe much sooner in Earth's history than has been generally theorized.

Professor Page Chamberlain, who led the study, said the findings also mean the chemical composition of the ancient ocean was significantly different from today's ocean, which in turn might change interpretations of how the early atmosphere evolved.

"By looking at both oxygen and hydrogen in these ancient rocks we were able to put some constraints on how different the ancient ocean composition may have been from today, and then use that composition to try to determine how hot the ancient ocean was," said researcher Michael Hren, the lead author of the study.

A paper describing the work that included co-author Mike Tice was published in the Nov. 12 early online edition of the journal Nature.