It is a priori necessary to predict that a potential storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site has a good sealing capacity, so that the injected CO2Carbon dioxide would be safely contained. The caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir and exiting wells are the main types of potential weak points in a storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere system. An accurate assessment of storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere performance may require the modelling of coupled processes: multiphase flow, kinetically-controlled geochemical reactions and geomechanical deformation. For example, porosityMeasure for the amount of pore space in a rock/permeabilityAbility to flow or transmit fluids through a porous solid such as rock of the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids rock may be altered due to concomitant mineral precipitation/dissolution and fractureAny break in rock along which no significant movement has occurred-aperture evolution (Johnson, 20092009 - J. W. JohnsonIntegrated modeling, monitoring, and site characterization to assess the isolation performance of geologic CO2 storage: Requirements, challenges, and methodologysee more). This interplay of geochemical and geomechanical processes, within both the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids and, most importantly, the caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir, can strongly influence storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere containmentRestriction of the movement of a fluid to a designated volume (e.g. reservoir), capacity and the CO2 plumeDispersing volume of CO2-rich phase contained in target formation distribution.
A series of dynamic flow simulation and geomechanical analysis models that are consistent with the geological model should be built to predict the impacts of the planned storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere operation. These models will usually only represent a sub-set of the domain for the geological model where CO2Carbon dioxide is expected to migrate, or geomechanical responses to any pressure increase which may occur (Aarnes et al., 2010). The model will allow prediction of flow of CO2Carbon dioxide from the injectionThe process of using pressure to force fluids down wells wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids(s) into the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it for the duration of injectionThe process of using pressure to force fluids down wells operations, and the long-term evolution of the CO2 plumeDispersing volume of CO2-rich phase contained in target formation after the cessation of injectionThe process of using pressure to force fluids down wells. The dynamic model should give quantified estimates of CO2Carbon dioxide volume, concentration and spatial distribution at an appropriate temporal resolution. In particular, the coupled geomechanical and flow simulations should be planned and executed to assess leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column probabilities and rates relative to key risks, such as:
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CO2Carbon dioxide entry into the caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir (e.g. due to pressure in excess of capillary entry pressureAdditional pressure needed for a liquid or gas to enter a pore and overcome surface tension of the caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir or due to caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir degradation);
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leakage(in CO2Carbon dioxide storage) The escape of injected fluid from the storage formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it to the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%) or water column through inadequately sealed wells;
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upward flux of CO2Carbon dioxide or formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it fluids in fractureAny break in rock along which no significant movement has occurred and fault(geology) A surface at which strata are no longer continuous, but are found displaced zones.
Coupled flow and geomechanical modelling studies increase our understanding as discussed in the following sections.