The U.S. Geological Survey (USGS) conducted a detailed assessment and found 36 regions across the country that have the proper subterranean conditions to store between 2,400 to 3,700 metric gigatons of carbon dioxide underground a process known as . One metric gigaton is equal to a billion metric tons.
In a separate report released in early June, the U.S. Energy Information Administration, an organization that collects and analyzes statistics on , projects the United States will emit approximately 5.4 metric gigatons of fossil fuel-related carbon dioxide in 2013, which includes coal, natural gas and petroleum emissions. Based on these estimates, the USGS findings represent a vast, untapped resource that could helpand mitigate the impact they have on Earths climate, said Briana Mordick, a geologist at the Natural Resources Defense Council (NRDC), a nonprofit environmental advocacy group headquartered in New York City.
"This is just one tool in a range of options that we have, but it's an important one to give us additional time to transition from fossil fuels to nonfossil fuel energy," Mordick told LiveScience. []
As part of its survey, the USGS excluded areas of the country that are considered freshwater sources, and limited their assessment to rock layers at depths at which thewould be under sufficient pressure to remain in a liquid state, which would help the carbon dioxide mix in with the briny water found underground.
The study identified the largest storage potential in the Coastal Plains region, which encompasses much of the Gulf Coast. This area could account for roughly 2,000 metric gigatons, or 65 percent, of the country's storage potential, according to the USGS report. Other areas with considerable storage capacity include the Alaska region and the Rocky Mountains.
Going beneath the surface
Geologic carbon sequestration involves capturing the exhaust gases from power plants before they are released into the , and separating the carbon dioxide from the rest of the emissions. This carbon dioxide is then cooled and compressed into a so-called supercritical state, which means it has properties between a liquid and a gas, Mordick explained.
Next, the supercritical carbon dioxide travels through a network of underground pipelines to a site where it is pumped through a well into subsurface rocks.
"The idea is that the carbon dioxide will be trapped there pretty much indefinitely," Mordick said. "Things like oil, gas and brine are trapped in the subsurface for millions of years, so basic geologic principles tell us this is possible. In some ways, it's mimicking ."
To do this, the carbon dioxide needs to be injected deep underground, between at least 3,000 and 15,000 feet (914 and 4,600 meters), said Peter Warwick, chief of the geologic carbon sequestration project at the USGS, which put out the sequestration report. In addition, certain types of rocks are more suited to hold carbon dioxide. [Video: ]
"You want a rock that has what we call porosity, which means there are small, open areas within the rock, and permeability, which is the ability for fluid to move through the rock," Warwick said.
Sandstone or limestone rock formations are particularly good storage reservoirs, but equally important are the layers of rock over the top that act as a cap, sealing in the carbon dioxide, Mordick said. Without this robust rock layer, carbon dioxide could seep out and leak to the surface, reaching the atmosphere anyway.
"There has to be a good ceiling formation above something like shale, with low porosity and low permeability," Mordick said. "Essentially, it's like a lid on top of the storage formation that prevents carbon dioxide from migrating vertically."
Leaks are one of the primary concerns surrounding geologic carbon sequestration, and researchers around the country are assessing the risks involved, which includes studying the types of conditions that could cause carbon dioxide to escape.
http://zuycmock.blogdetik.com/2013/06/26/download-suspectvictim-e-book/
http://en.netlog.com/corazonwein/blog/blogid=25685571
http://patrickyuoyu.webs.com/apps/blog/show/29262568
http://christalefi.skyrock.com/3170712629-Download-The-Dieter-s-Paradox-Why-Dieting-Makes-Us-Fat-e-book.html
http://blog.yahoo.com/_EBS6ZYDFCXJN7LEZ6SFHVIBVP4/articles/1276009
http://blog.yahoo.com/_RNHF73YFCWR2DDFS2JTFFGKQTU/articles/1376751
http://en.netlog.com/bradnovoa/blog/blogid=25685580
http://friendfeed.com/rvdmdaa/ac72a4f2/heaven-and-earth-three-sisters-island-trilogy
http://friendfeed.com/ucyiur/21173641/orlando-innamorato-book-downloads
http://twitpic.com/czi279
http://annitaria.soup.io/post/321514760/Christian-Baptism
http://oaloqmpfpq.blogdetik.com/2013/06/24/downloads-print-ad-1966-motorola-x11-solid-state-signal-sensor-e-book/