Abstract:

Abstract: Strong heterogeneity exists in multistage sandstone reservoirs of underwater distributary channel microfacies of shallow water delta in the lower Minghuazhen Formation in the Bozhong263 oilfield,Bohai Bay Basin.In this paper,we quantitatively describe the plane heterogeneity of reservoirs through integration of seismic and logging data.The quantitative description of heterogeneity is then to be taken into consideration in geologic modeling and well emplacement,so as to reduce reserve risk,confirm the resources,optimize the location of development wells,direct the composing of Overall Development Plan and make other decisions.Petrophysical analysis indicates that the pseudoimpedance can differentiate the variety of sandstone and shale perfectly.The amplitude and coherence information extracted from the impedance volume can be used to identify the plane variety of lithofacies and the distribution of abandoned channel,point bar,and small faults.They also can be used to constrain the variety of plane permeability during petrophysical modeling.Some virtual faults can be introduced to reflect the interior disconnectivity of sand body.Besides,by using the spectral decomposition technique deriving from short time window Fourier transformation and the absorbing attenuation phenomenon in differential frequency spectrum,this paper studies the latteral variety of reservoir,quantitatively calculates their thickness.Hydrocarbonbearing sand body is successfully detected in this way.