19 Mar 2013:
New Carbon Storage Method
Reduces Earthquake Risk, Study Says
A team of researchers says it has demonstrated a method of underground carbon storage that reduces the risk of triggering earthquakes
, a safety concern cited by some scientists about the emerging field of carbon capture and sequestration. While often cited as a potentially key option in reducing atmospheric levels of carbon dioxide, earlier studies
have suggested that the use of carbon sequestration technologies in some rock formations can result in leaks that ultimately cause minor tremors. But in a new study, published in the journal Geophysical Research Letters
, Yale University researchers say that storing carbon in a common type of volcanic rock, known as reactive mafic rock, offers a far safer alternative. According to their findings, injecting carbon into the mafic rock causes a chemical reaction that generates carbon minerals, creating a so-called “mineral-trapping” phenomenon that reduces fluid pressure, distributes the stress load, and increases frictional contact, which in turn minimizes seismic risks. “Not only do the new carbonate minerals safely store CO2, but they possibly have the added benefit of reducing fluid pore pressure and distributing the stress at the injection site, both of which mitigate seismic risk,” said Dave Bercovici, a professor of geophysics at Yale and the lead investigator in the study.