Reservoir Fluids Type Identification Using Resistivity and Sonic Logging Data in Sandstone Reservoir

The paper focuses on the use of shallow and deep resistivity logging data readings and presented new factor: hydrocarbon moveability factor (HCM), it is a good indicator to the hydrocarbon moveability and also recovery factor prediction and also this approach provides the water saturation values. HCM factor varies from zero to one, it indicates hydrocarbon moveability (0.25 <HCM <0.75). When HCM is greater than 0.75, it indicates that the oil will not be produced and if HCM is less than 0.25, it indicate the zone may produce oil with high GOR or gas. The second part uses sonic logging data; compressional wave travel time (∆tp) and shear travel time (∆ts) to determine Vp/Vs ratio. The use of Vp/Vs crossplot to identify fluid type is based on the fact that shear wave is more sensitive than P-wave to fluid change, consequently, Vp/Vs might be more sensitive to fluid change from water to oil to gas than either Vp or Vs. ΔTp – ΔTs crossplot is preferred rather than the form of Vp/Vs crossplot. It is technically easier; values are taken directly from records to the crossplot