System and method for determining water-filled porosity and water salinity in well cores and logs

A system for determining water-filled porosity and water salinity in a well, the system comprising:

• a dielectric apparatus comprising a dielectric probe, a frequency sweep signal generator, a porosity and salinity logical circuit, and a graphical user interface;
• wherein the frequency sweep signal generator is configured to generate a broadband signal over a selected frequency range;
• and
• the porosity and salinity logical circuit comprises a processor and a non-transitory medium with computer executable instructions embedded thereon, the computer executable instructions configured to:
• obtain a complex dielectric permittivity from a dielectric probe applied to a well core or from well logs stored in a memory;
• select a dielectric mixing law with the index number m;
• calculate an m-th root of complex dielectric permittivity over the selected frequency range;
• plot, on the graphical user interface (GUI), a m-th root of complex dielectric permittivity over the selected frequency range in a complex domain, wherein m is an index number;
• determine a matrix permittivity, a water salinity, and a water-filled porosity based on the complex dielectric permittivity and the dielectric mixing law;
• and
• display the water salinity and the water-filled porosity on the GUI.

A computer-implemented method of determining water-filled porosity and water salinity in a well, the method comprising:

• obtaining, from well logs stored in a memory, a complex dielectric permittivity of earth formations;
• selecting a dielectric mixing law with the index number m;
• calculating an m-th root of complex dielectric permittivity;
• plotting, on a graphical user interface (GUI), a m-th root of complex dielectric permittivity over the selected frequency range in a complex domain, wherein m is an index number;
• determining, with a porosity and salinity logical circuit, a matrix permittivity, a water salinity, and a water-filled porosity based on the complex dielectric permittivity and the dielectric mixing law;
• and
• displaying the water salinity and the water-filled porosity on the GUI.