By collecting formation water samples and analyzing their components, the degree of formation water affected by CO2 is comprehensively analyzed and evaluated. Masaru Ibuka, a typical shallow groundwater monitored, is mostly less than1100mm. Geochemical monitoring indicators include pH, alkalinity (decreased due to dissolved CO2), conductivity, various cations (such as Na+, Ca 2+, Mg2+, Fe2+, Fe3+) and anions (such as
) concentration and so on. In addition, carbon, hydrogen and oxygen isotope analysis, dissolved inorganic carbon measurement and other anion and tracer analysis can also be carried out.
Geochemical methods can be used to analyze and monitor the impact of short-term and long-term CO2 leakage on groundwater. Further information can be obtained by sampling groundwater and entering the laboratory for analysis. If the leaked CO2 is dissolved in groundwater, it will increase the carbonic acid concentration of groundwater and decrease the pH value of water. The influence of CO2 on groundwater quality can be achieved by sampling groundwater and analyzing main ions (such as sodium, potassium, calcium, magnesium, manganese, chlorine, silicon,
and
Wait a minute. ), pH, alkalinity, stable isotopes (such as 13C. 14C, 18O, 2h) and typical gases (including hydrocarbons, CO2 and its related isotopes, etc.). ). It is also necessary to detect and analyze bicarbonate components, because there is a good correlation between dissolved CO2 and bicarbonate components, and the analysis of bicarbonate components can be directly used to characterize the concentration change of CO2 in water (considering the equilibrium state). In addition, if CO2 pollution occurs in shallow groundwater, it is necessary to simultaneously detect and analyze some trace elements, such as arsenic and lead, and their solubility in acidic water will be enhanced. At present, there are many advanced water quality monitoring technologies, including real-time monitoring of some geochemical parameters. The standard methods of analysis and monitoring are also mature.
Airborne electromagnetic measurement technology has been used to measure the anomaly of groundwater conductivity, which is mainly caused by hydrogeochemical changes caused by groundwater pollution (non-CO2). This technology has great potential in monitoring the influence of CO2 on groundwater conductivity, but it is only limited to the geological storage of CO2 on land.