| Summary: | <p> The presence of shale in a sandstone reservoir can negatively affect the producibility of that reservoir. It is hence important to quantify not only the volume of shale but also the distribution types. The shale distribution types are described as laminar shale, dispersed shale, and structural shale. The shale distribution types can exist in any number of combinations in a reservoir. However, most previous works have considered only the single-type distribution models (laminar, dispersed, and structural shales) and the two-type laminar-dispersed and laminar-structural models. A previous thesis expanded on previous works to include the dispersed-structural and three-type shale distribution system, expanding the total porosity versus total volume of shale crossplot technique, and devised the ratio method for further analysis. This research provides an additional methodology to quantify the shale distribution types using the density porosity versus neutron-density volume of shale crossplots. Applying the ratio method in terms of the gamma-ray volume of shale and neutron-density volume of shale showed that considering a third component in the volume of shale distribution led to an increase in the volume of dispersed shale. Both the laminar-dispersed and laminar-structural models provide the most optimistic scenarios in the reservoir where the volume of dispersed shale is calculated at its lowest potential value and, hence, the effective sandstone porosity is highest. The ratio method allows for the calculation of a range of scenarios starting from the most optimistic to the most pessimistic. Using the VshND tool as an additional method in a case study in this work revealed that the VshND calculated the volume of shale at higher values than the VshGR, thus providing a more conservative analysis in this case.</p><p>
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