Hi Rodger, Thanks for your input on this. It's nice to have a geologist on the list. Just goes to prove that UA knows all. I downloaded the latest Science Friday podcasts and, by coincidence, one of the segments was on "Deep-Sea Carbon Sequestration" and featured the director of something called the Borehole Research Group. They talked about liquifying CO2 and pumping it into voids in the ocean floor. The idea is since it's heavier than water it would stay put and eventually react with whatever's down there and turn permanently into chalk. They stated there's room enough in a spot off the NW corner of the us to sequester the next 150 year's worth of the US's CO2 output. More details here: http://www.sciencefriday.com/program/archives/200807255 patrick On 28 Jul 2008, at 17:41, Rodger Fry wrote:
In the oceans, CO2 precipitates out of water via biochemical & physical action. Many marine organisms absorb CO2 from sea water and use this in forming their shell in the case of mallusks and crustaceons or their colony as in the case of coral.
Chemically, when CO2 rich waters are drawn deep in the benthic areas of the oceans, the pH and temperature conditions are right for the precipication of Calcium and Magnesium carbonates. This forms the minerals Calcite and Dolomite that are the two most common minerals in marine limestones.
Removal of CO2 from the biosphere occurs through photosynthesis in the chloroplasts of plants both marine and sub-aerial.