Consortium for Ocean Leadership (February 5, 2010)
"The chemical composition of our oceans is not constant but has varied significantly over geological time."
"(From ScienceDaily) -- In a study published in Science, researchers describe a novel method for reconstructing past ocean chemistry using calcium carbonate veins that precipitate from seawater-derived fluids in rocks beneath the seafloor.
"The research was led by scientists from the University of Southampton's School of Ocean and Earth Science (SOES) hosted at the National Oceanography Centre, Southampton (NOCS).
" 'Records of ancient seawater chemistry allow us to unravel past changes in climate, plate tectonics and evolution of life in the oceans. These processes affect ocean chemistry and have shaped our planet over millions of years,' said Dr Rosalind Coggon, formerly of NOCS now at Imperial College London...."
What seawater tasted like a hundred million years ago may not be a fascination for you. But I think it's another piece in the puzzle of what's happened in the four billion or so years that Earth has been around. And, as such, quite interesting.
And yes, I am curious about really old seawater. Particularly now that there's a chance to find out something about it.
The scientists are piecing together the ratio of strontium to calcium (Sr/Ca) and magnesium to calcium (Mg/Ca) during the last 170,000,000 years. They're using basalt seafloor core samples taken over the last few decades.
They found that seawater older than 25,000,000 years had less of those elements in it than seawater has had for the last couple dozen millions of years.
Getting a little off-topic: There were folks who had a hard time dealing with change in my youth, and there still are.
I sympathize, in a way. I liked looking at a lake, between Minneapolis and Moorhead, Minnesota, back in the seventies. Most of it's a marsh now. The same's happening with most Minnesota lakes. No surprises there. We're coming out of a glacial period - and that's what happens to the puddles left by glaciers as they melt.
Change happens.
Which is why you won't see recipes that call for fresh trilobite.
Almost-related posts:
- "Change, American Culture, Trilobites, Humanity's History, and the Big Picture"
(Last updated January 5, 2010) - "Frail, Delicate Little Mother Nature?!"
(December 20, 2009)
A tip of the hat to CRKARLA and therightblue, on Twitter, for the heads-up on this article.
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