2.1 CO2 plume migration in the storage reservoir

Subsurface monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions techniques play a vital role in identifying CO2 plumeDispersing volume of CO2-rich phase contained in target formation location, pressure propagation, and reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids and sealAn impermeable rock that forms a barrier above and around a reservoir such that fluids are held in the reservoir integrity. These techniques can detect CO2Carbon dioxide and compare observations with the predicted fate and transport results from modelling efforts. Many techniques can be imported from oil and gas exploration and reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids management disciplines. A variety of techniques is also available to assess the condition of the wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids and ensure that the wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids itself does not provide a leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column pathway for CO2Carbon dioxide migrationThe movement of fluids in reservoir rocks.

However, no techniques are available to measure the CO2Carbon dioxide in situ with precision. Therefore, it is not possible to directly quantify CO2Carbon dioxide in the injectionThe process of using pressure to force fluids down wells zone. Hence, it is necessary to use indirect or inferential methods to document that the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site is performing as expected and that CO2Carbon dioxide and brine are not escaping the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids in unacceptable directions and at unacceptable rates.

For geological storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere, CO2Carbon dioxide is injected at depths of ³ 800 m so that it will be present as a supercritical(CO2) Conditions where carbon dioxide has some characteristics of a gas and some of a liquid fluid under typical temperature and pressure conditions prevailing at these depths. Since compressibility and density of supercritical(CO2) Conditions where carbon dioxide has some characteristics of a gas and some of a liquid CO2Carbon dioxide are smaller in comparison to those of saline formationUnderground rock where saline water occupies the tiny spaces between the grains of rock water, the pore spaceSpace between rock or sediment grains that can contain fluids in a saline aquiferAn underground layer of fluid-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) with significant permeability to allow flow will be filled with a less compressible and less dense fluidA gas compressed to a density approaching that of the liquid after substituting formation waterWater that occurs naturally within the pores of rock formations by injected CO2Carbon dioxide. This contrast in properties is useful for different geophysical monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions techniques. The situation is more complicated in depleted(hydrocarbon reservoir) one where production is significantly reduced hydrocarbon reservoirs due to the large variations in the physical properties of oil, and since CO2Carbon dioxide will modify the physicochemical properties of the oil in short time scales.

A recent overview of the different geophysical monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions techniques can be found in Sayers and Wilson (2010). Estimates of CO2Carbon dioxide detection limits for some of the most commonly used geophysical methods are given by JafarGandomi and Curtis (2011). Tab. 2-1 gives a summary of the most common monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions techniques to monitor CO2Carbon dioxide injectionThe process of using pressure to force fluids down wells and follow the migrationThe movement of fluids in reservoir rocks of the CO2 plumeDispersing volume of CO2-rich phase contained in target formation.