Carbon in the environment form the carbon cycle. For example, photosynthetic plants draw carbon dioxide from the atmosphere (or seawater) and build it into biomass, as in the Calvin cycle, a process of carbon fixation. Some of this biomass is eaten by animals, while some carbon is exhaled by animals as carbon dioxide. The carbon cycle is considerably more complicated than this short loop; for example, some carbon dioxide is dissolved in the oceans; if bacteria do not consume it, dead plant or animal matter may become petroleum or coal, which releases carbon when burned. Carbon can form very long chains
Carbon dioxide flooding Carbon dioxide flooding Carbon dioxide (CO) flooding is a process whereby carbon dioxide is injected into an oil reservoir in order to increase output when extracting oil. When a reservoir’s pressure is depleted through primary and secondary production, carbon dioxide flooding can be an ideal tertiary recovery method. It is particularly effective in reservoirs deeper than 2,500 ft., where will be in a supercritical state, with API oil gravity greater than 22–25° and remaining oil saturation greater than 20%. Carbon dioxide flooding is not affected by the lithology of the reservoir area, but simply by the reservoir porosity and permeability,