Tag Archives: seawater chemistry

Liquid calcium carbonate

Geologist Adam Wallace reports in ‘Science’ that calcium carbonate has a dense liquid phase

Computer simulations could help scientists make sense of a recently observed and puzzling wrinkle in one of nature’s most important chemical processes. It turns out that calcium carbonate — the ubiquitous compound that is a major component of seashells, limestone, concrete, antacids and other naturally and industrially produced substances — may momentarily exist in liquid form as it crystallizes from solution.

“Our simulations suggest the existence of a dense liquid form of calcium carbonate,” said co-corresponding author Adam Wallace, an assistant professor of geological sciences in UD’s College of Earth, Ocean, and Environment who conducted the research while a postdoctoral researcher at the Lawrence Berkeley National Laboratory. “This is important because it is an as-yet unappreciated component of the carbon cycle.” (more…)

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Ancient Alteration of Seawater Chemistry Linked With Past Climate Change

Dissolution or creation of huge gypsum deposits changed sulfate content of the oceans

Scientists have discovered a potential cause of Earth’s “icehouse climate” cooling trend of the past 45 million years. It has everything to do with the chemistry of the world’s oceans.

“Seawater chemistry is characterized by long phases of stability, which are interrupted by short intervals of rapid change,” says geoscientist Ulrich Wortmann of the University of Toronto, lead author of a paper reporting the results and published this week in the journal Science.

“We’ve established a new framework that helps us better interpret evolutionary trends and climate change over long periods of time. The study focuses on the past 130 million years, but similar interactions have likely occurred through the past 500 million years.” (more…)

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