Gaseous Reservoir Horizons Determination via Vp/Vs and Q-Factor Data, Kangan-Dalan Formations, in One of SW Iranian hydrocarbon Fields

An important method in oil and gas exploration is vertical seismic profile (VSP) to estimate rock properties in drilling well. Quality factor is also the crucial point of seismic attenuate in VSP data. In the present study, this factor was used to evaluate the hydrocarbon potential of Kangan Formation in one of the Persian Gulf oil fields using VSP zero offset method. Quality factor was estimated using VSP spectral ratio method. Density and porosity logs are also used to determine lithology and reservoir fluid types. Analysing Vp/Vs ratio changes is a useful tool to detect hydrocarbon accumulation. These points marked by high amplitude energy in seismograms in correlation with petrophysical logs. According to Vp/Vs plots and geological logs of the field revealed that Vp/Vs ratio is increased at depths indicating hydrocarbon presence. Data are showing good correlation to petrophysical logs. Therefore, VSP method can be applied as a suitable alternative method to find hydrocarbon reserves in those boreholes without petrophysical logs.