Dielectric Mixing Laws For Fully And Partially Saturated Carbonate Rocks Available to Purchase

Dielectric wireline logs have traditionally been used for determining water-filled porosity in the flushed zone. In carbonates, the flushed zone water saturation is often used to back out a variable ?m? for insertion into Archie?s law to calculate the water saturation of the uninvaded zone. One of the advantages of using dielectric logs for this technique is their ability to calculate formation water saturation fairly independent of salinity. There are, however, over a dozen different mixing laws proposed to do this. The most widespread mixing law used is the Complex Refractive Index Measurement (CRIM). In this paper an extensive study was undertaken over a wide range of fully and partially saturated cores to determine the most appropriate dielectric mixing laws in carbonates. This study focuses on carbonates since their limited mineralogical range reduces the number of variables in the mixing laws. A new coaxial-circular dielectric cell was constructed to measure standard cores 1.5 inch in diameter and 1.5 inch long. This new cell represents a significant step forward for dielectric studies because earlier devices could only measure thin discs or coaxially drilled cores which are more difficult to partially saturate under controlled conditions. With the new measurement cell, the cores can be partially saturated by centrifugation to different oil-water saturations. The saturation values are doublechecked by weight and also independently by nuclear magnetic resonance measurements in the laboratory. The dielectric constants of the fully and partially saturated cores were measured over a wide frequency range from 300 KHz to 3 GHz. The results of the core measurements were then compared against several mixing laws. These mixing laws are model-based and require knowledge of the dependence of the dielectric constant of the constituents. We tested the models containing only volumetric parameters as variables. These models are most practical for single-frequency dielectric logging tools. Dielectric wireline logs have traditionally been used for determining water-filled porosity in the flushed zone. In carbonates, the flushed zone water saturation is often used to back out a variable ?m? for insertion into Archie?s law to calculate the water saturation of the uninvaded zone. One of the advantages of using dielectric logs for this technique is their ability to calculate formation water saturation fairly independent of salinity. There are, however, over a dozen different mixing laws proposed to do this. The most widespread mixing law used is the Complex Refractive Index Measurement (CRIM). In this paper an extensive study was undertaken over a wide range of fully and partially saturated cores to determine the most appropriate dielectric mixing laws in carbonates. This study focuses on carbonates since their limited mineralogical range reduces the number of variables in the mixing laws. A new coaxial-circular dielectric cell was constructed to measure standard cores 1.5 inch in diameter and 1.5 inch long. This new cell represents a significant step forward for dielectric studies because earlier devices could only measure thin discs or coaxially drilled cores which are more difficult to partially saturate under controlled conditions. With the new measurement cell, the cores can be partially saturated by centrifugation to different oil-water saturations. The saturation values are doublechecked by weight and also independently by nuclear magnetic resonance measurements in the laboratory. The dielectric constants of the fully and partially saturated cores were measured over a wide frequency range from 300 KHz to 3 GHz. The results of the core measurements were then compared against several mixing laws. These mixing laws are model-based and require knowledge of the dependence of the dielectric constant of the constituents. We tested the models containing only volumetric para