Dec 15, 2010 11:45 GMT  ·  By
If sequestration does become a major part of the effort to reduce greenhouse gases, a public education campaign will be needed, said Stanford geophysicist Mark Zoback
   If sequestration does become a major part of the effort to reduce greenhouse gases, a public education campaign will be needed, said Stanford geophysicist Mark Zoback

One of the most widely-researched methods of disposing of excess carbon dioxide in Earth's atmosphere is to literally sweep it under the rug, inside underground caverns and deposits. However, a new study suggests that this is not necessarily the wisest thing to do.

While combating global warming should undoubtedly be a priority for us, we should also take into account the effects that pumping millions of tons of CO2 underground will have.

According to the new study, it would appear that carbon capture and storage systems (CCS) could be breached, and then fail, by their own hand. The deposits might be capable of triggering small tremors, that would destabilize the areas where they were built.

This would crack the caverns or deposits, releasing the carbon dioxide all at once. This scenario was developed by geophysicist Mark Zoback, who is based at the Stanford University.

The expert argues that this is a serious obstacle in the path of adopting CCS technologies at a scale large enough for the technique to make any difference in atmospheric CO2 levels.

Around the world, thousands of carbon injection sites will have to be built. While the tremors they could produce would not be powerful enough to hurt people or damage property, the ground movements would still destabilize the deposits.

“It is not the shaking an earthquake causes at the surface that creates the hazard in this instance, it is what it does at depth,” Zoback explains.

“It may not take a very big earthquake to damage the seal of an underground reservoir that has been pumped full of carbon dioxide,” he argues. Naturally, once this happens, the contents of the reservoir would be released back into the atmosphere.

CO2 is currently produced in vast amounts by coal-burning power plants and refineries, as well as by the burning of fossil fuels in engines. The largest polluters are the United States, China and India.

Scientific studies have determined that carbon is the primary cause of anthropogenic global warming, and subsequent climate change, and have called for politicians to take firm steps in reducing pollution.

At this point, a host of geoengineering schemes are making the rounds, and CCS is one of them. Whether it will win the competition, or some other technique will, still remains to be seen.

“I am not against carbon dioxide sequestration by any means and it certainly has a role. What I am asking people to consider is whether or not it should really be one of the key components of a strategy for reduction of greenhouse gas,” Zoback concludes.