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Press Release 07-109
Volcanic Activity Key to Oxygen-rich Atmosphere
Activity contributed to rise of complex biological forms
August 29, 2007
Next time you catch a breath, be thankful, for a change, that the Earth's surface is dotted with volcanoes.
National Science Foundation-funded research published this week in the journal Nature indicates that billions of years ago, when the Earth was home largely to undersea volcanoes, some previously unknown agent was removing the gas.
The researchers suggest that mixture of gases and lavas produced by submarine volcanoes scrubbed oxygen from the atmosphere and bound it into oxygen-containing minerals.
Lee R. Kump, a professor of geosciences at Penn State University, working with a colleague at the University of Western Australia, looked at the geologic record from the Archaean--a geologic period from 3.8 to 2.5 billion years before the present day--and the Palaeoproterozoic-- geologic era immediately following that featured profound global change that included the breakup and formation of two supercontinents. They found that in the Archean there was a dearth of terrestrial volcanoes, while in the Palaeoproterozoic, although submarine volcanoes continued to be common, the population of terrestrial volcanoes increased dramatically.
"The rise of oxygen allowed for the evolution of complex oxygen-breathing life forms," Kump said.
Terrestrial volcanoes could become much more common because land masses stabilized and the current system of tectonics regime took shape.
Because submarine volcanoes erupt at lower temperatures than terrestrial volcanoes, they are more efficient at converting--or "reducing"--oxygen. As long as the reducing ability of the submarine volcanoes was larger than the amounts of oxygen created, the atmosphere had no oxygen. When terrestrial volcanoes began to dominate, oxygen levels increased.
The change over time caused an atmospheric shift from oxygen-free to oxygen-rich, the researchers argue, with profound implications for life on the planet.
-NSF-
Media Contacts
Peter West, NSF (703) 292-7761 pwest@nsf.gov
A'ndrea Messer, Penn State University (814) 865-9481 aem1@psu.edu
Principal Investigators
Lee R. Kump, Penn State University (814) 863-1247 kump@essc.psu.edu
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2009, its budget is $9.5 billion, which includes $3.0 billion provided through the American Recovery and Reinvestment Act. NSF funds reach all 50 states through grants to over 1,900 universities and institutions. Each year, NSF receives about 44,400 competitive requests for funding, and makes over 11,500 new funding awards. NSF also awards over $400 million in professional and service contracts yearly.
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