Monitoring Remaining Oil Saturation Using Carbon/Oxygen Logging Technique in CO2 Injection Reservoirs
F. Zhang, Q.Y. Zhang, J.T. Liu, Z.Y. Han and Q. Chen
Event name: 78th EAGE Conference and Exhibition 2016
Session: CO2 Sequestration and Storage
Publication date: 31 May 2016
Info: Extended abstract, PDF ( 1.27Mb )
Price: € 20
The remaining oil or gas saturation are necessary to determine in CO2 injected floods for evaluate EOR or EGR. After injecting CO2 flood, the component and density of CO2 are different from water and oil, and it results in the different capacities of slowing down and capturing neutron, the C/O value and capture gamma ratio increase with the increasing of oil saturation. Therefore, remaining oil saturation can be still monitored using C/O spectroscopy logging after injecting CO2 flood. The porosity and borehole fluid affect the C/O spectroscopy logging. Large porosity is beneficial for fluid identification. And borehole fluid should be corrected when C/O logging is used to monitor remaining oil saturation. In addition, the example shows the C/O ratios difference before and after injecting CO2 into reservoir can reflect the remaining oil saturation. The result will provide theoretical support for quantitative interpretation remaining oil saturation in the CO2 injection reservoir.