Application of seismic attributes in petrophysical model construction, Miocene deposits in the Carpathian Foredeep

The aimof this studywas to predict reservoir parameters distribution in Miocene deposits. The area of interest is located in the Carpathian Foredeep, where many deposits of natural gas such as Sędziszów (Zagórzyce), Nosówka and Góra Ropczycka are known. The results of the analysis verified existing gas fields and identified new anomalous zones. The main advantage of presented method is the integration of geological, petrophysical and seismic data. For the purpose of modelling of petrophysical parameters distribution (e.g. porosity, density, gamma ray), results of inversion, well logs and seismic attributes were used. On the basis of structural interpretation of 3D seismic data, the structure framework was built. The entire model was divided into four Miocene's complexes and then split it into layers of 10 m thickness. All used well logging data were scaled to the spatial resolution of the structural model. Estimation of petrophysical parameters was performed using advanced algorithms available in Petrel (Neural Net, Gaussian Random Function Simulation). A number of seismic attributes (e.g. Sweetness, Envelope, Local Flatness, Relative Acoustic Impedance, Dominat Frequency, Chaos, Acoustic Impedance) were used to steer the distribution of petrophysical well data. The study provided information about the distribution of petrophysical properties at every point of the spatial model of Miocene complex. The results show high correlation of seismic attributes and petrophysical properties of the data from the area of Góra Ropczycka–Iwierzyce 3D seismic project. On the basis of all available reservoir information, geobodies have been extracted. Petropysical model prediction is fundamental in understanding clastic reservoirs and should be used for prospect identification