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Liquid calcium carbonate

By Guest PostAugust 23, 2013Environmentalloys, antacids, atmospheric, calcium carbonate, calcium carbonate mineralization, carbon cycle, carbon dioxide levels, carbon storage reservoirs, concrete, crystallization pathway, dense liquid droplets, dense liquid phase, energy barrier, geologist adam wallace, limestone, liquid calcium carbonate, marine organisms, molecular dynamics simulations, nanoscale phase, nanoscopic clusters, polymers, salt solutions, seashells, seawater chemistry

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…)

New CU-Boulder led research effort dates oldest petroglyphs known in North America

By Guest PostAugust 17, 2013Environmentarchaeologists, benjamin aleck, boulder, boulders, carbonate coating, cave in oregon, elevation, emerson pass, eugene hattori, fossilized human excrement, lahontan basin, larry benson, limestone, maximum height, native american artifacts, North America, northeast of reno, oldest petroglyphs, pyramid lake, university of colorado, water level, western nevada, winnemucca lake, winnemucca lake petroglyphs, winnemucca lake subbasin

A new high-tech analysis led by a University of Colorado Boulder researcher shows the oldest known petroglyphs in North America, which are cut into several boulders in western Nevada, date to at least 10,500 years ago and perhaps even as far back as 14,800 years ago.

The petroglyphs located at the Winnemucca Lake petroglyph site 35 miles northeast of Reno consist of large, deeply carved grooves and dots forming complex designs on several large limestone boulders that have been known about for decades, said CU-Boulder researcher Larry Benson, who led the new effort. Although there are no people, animals or handprint symbols depicted, the petroglyph designs include a series of vertical, chain-like symbols and a number of smaller pits deeply incised with a type of hard rock scraper. (more…)

Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions

By Guest PostJune 24, 2013Scienceals, ancient seawater concrete, berkeley lab, bessy synchrotron, chemical attack, cutting carbon emissions, drill core, emperor augustus, environmentally damaging, Germany, greenhouse gas emissions, gulf of naples, king abdullah university, library foundation, limestone, loeb classical, marie jackson, mediterranean sea, modern world, paulo monteiro, pliny the elder, pompeii, portland cement, pozzolan, pozzuoli bay, roman concrete, roman harbor, roman seawater concrete, samples, saudi arabia, secret, vitruvius, volcanic ash

Berkeley Lab scientists and their colleagues have discovered the properties that made ancient Roman concrete sustainable and durable

The chemical secrets of a concrete Roman breakwater that has spent the last 2,000 years submerged in the Mediterranean Sea have been uncovered by an international team of researchers led by Paulo Monteiro of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), a professor of civil and environmental engineering at the University of California, Berkeley.

Analysis of samples provided by team member Marie Jackson pinpointed why the best Roman concrete was superior to most modern concrete in durability, why its manufacture was less environmentally damaging – and how these improvements could be adopted in the modern world. (more…)

UF Pine lsland Pollen Study Leads to Revision of State’s Ancient Geography

By Guest PostMarch 3, 2011Scienceavon park formation, calusa indian village, david jarzen, deep injection well, early eocene, evolution of mammals, florida, flowering plants, fort myers, fossils, fredrick rich, geologic history, gray lignitic clay, jonathan bloch, limestone, marine environments, oligocene epoch, paleontologist, phytoplankton, pine island, pollen, sea level

GAINESVILLE, Fla. — A new University of Florida study of 45-million-year-old pollen from Pine Island west of Fort Myers has led to a new understanding of the state’s geologic history, showing Florida could be 10 million to 15 million years older than previously believed.

The discovery of land in Florida during the early Eocene opens the possibility for researchers to explore the existence of land animals at that time, including their adaptation, evolution and dispersal until the present. (more…)

Tag Archives: limestone

Liquid calcium carbonate

New CU-Boulder led research effort dates oldest petroglyphs known in North America

Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions

UF Pine lsland Pollen Study Leads to Revision of State’s Ancient Geography