Method for identification of origin of carbon-dioxide flow measured on surface of ground, involves identifying deep origin of flow of carbon-dioxide when volume of carbon-dioxide becomes independent of nitrogen/oxygen ratio

摘要

The method involves jointly measuring the volumetric quantities of carbon-dioxide (CO2), oxygen (O2), and nitrogen (N2), and determining a relationship between the volume of CO2 and N2/O2 ratio. A deep origin of flow of CO2 is identified when the volume of CO2 becomes independent of the N2/O2 ratio, where measurements are performed on a surface that is vertical or nearly vertical to a geological reservoir containing CO2, before CO2 injection operations in the reservoir.