Since CO2Carbon dioxide is less dense than saline water, it tends to migrate upward within the saline aquiferAn underground layer of fluid-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) with significant permeability to allow flow system; therefore, a caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir above the storage(CO2Carbon dioxide) A process for retaining captured CO2Carbon dioxide, so that it does not reach the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%) unit is required. Caprocks significantly retard the movement of fluids (Couples, 20052005 - G. D. CouplesSeals: The Role of Geomechanics. In Evaluating Fault and Caprock Seals.see more). Without a caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir, hydrocarbons (oil or gas) generated at depth would have long ago migrated toward the surface and either biodegraded to heavier oil or escaped to the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%). In the same manner, injected CO2Carbon dioxide will not remain trapped in a storage(CO2Carbon dioxide) A process for retaining captured CO2Carbon dioxide, so that it does not reach the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%) reservoirA subsurface body of rock with sufficient porosityMeasure for the amount of pore spaceSpace between rock or sediment grains that can contain fluids in a rock and permeabilityAbility to flow or transmit fluids through a porous solid such as rock to store and transmit fluids unless adequate caprocks are present.
Caprocks are an essential geological element of petroleum and CO2Carbon dioxide Reservoirs. A caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir (i.e., sealAn impermeable rock that forms a barrier above and around a reservoirA subsurface body of rock with sufficient porosityMeasure for the amount of pore spaceSpace between rock or sediment grains that can contain fluids in a rock and permeabilityAbility to flow or transmit fluids through a porous solid such as rock to store and transmit fluids such that fluids are held in the reservoirA subsurface body of rock with sufficient porosityMeasure for the amount of pore spaceSpace between rock or sediment grains that can contain fluids in a rock and permeabilityAbility to flow or transmit fluids through a porous solid such as rock to store and transmit fluids) is a low-permeabilityAbility to flow or transmit fluids through a porous solid such as rock lithological unit capable of impeding hydrocarbon or CO2Carbon dioxide movement upward, causing these buoyant fluids and gases to spread laterally, filling any stratigraphicThe order and relative position of geological strata or structural it encounters. Effective caprocks for liquid and gaseous accumulations are typically thick, laterally continuous, ductile rocks with high capillary entry pressures. The most common caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir lithologies over commercial petroleum reservoirs are evaporates and Shales. There may be several layers of caprocks. The lowermost caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir directly overlying the reservoirA subsurface body of rock with sufficient porosityMeasure for the amount of pore spaceSpace between rock or sediment grains that can contain fluids in a rock and permeabilityAbility to flow or transmit fluids through a porous solid such as rock to store and transmit fluids is then called the principal caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir and the overlaying layers of caprocks are referred to as secondary caprocks.