Study Of The Geological And Seismic Characteristics On Lithologic Reservoir

The lithologicalpool exploration is very difficult. The main reason is that we don't have enough knowledge of lithologicalpool and its seismic wave field. So it's important to have an in-depth study to geological geophysical features of the lithologicalpool. In order to establish a connection between geological characteristics of weak reflected lithologicalpool and its geophysical characteristics, this paper conducts the seismic forward modeling mainly based on zoeppritz equation and numerical simulation method. On this base, this paper studies the seismic response characteristics of weak reflected lithologicalpool with different petrophysical conditions (reservoir thickness, fluid saturation, reservoir porosity, etc.) and different lithologic combination and tectonic background. Then the relationship between petrophysical conditions and seismic attributes (waveform, amplitude, frequency and phase, etc) of weak reflected lithologicalpool can be summarized.The characteristics of thin interbedded reservoir seismic reflection characteristics and seismic resolution caused by different affecting factors is studied by means of seismic forward modeling based on different thin interbedded reservoir model. The forward modeling results show that thin interbedded thickness, wavelet frequency and phase, internal structure affect the thin interbedded seismic reflection characteristics in different degree. In addition, the difference in petrophysical characteristic is the main factor which decides the strength of reflective amplitude of thin interbedded. The one-way wave equation has many advantages: high calculating efficiency, useful in velocity modeling for its matching of regular migration algorithms, flexibly controlling wave-field that is simulated. It can not only simulate various kinds wavefields at the same time, but also separately simulate wavefield that is required. This paper conducts seismic forward modeling and prestack depth migration to typical lithologicalpool based on Pade screen operator for the reason that Pade screen operator can well adapt the strong lateral velocity contrasts.This paper studies the seismic response characteristics of weak reflected lithologicalpool and its recognition method. It emphatically introduced the identification method to thin sand top and bottom reflection interface based on the instantaneous phase difference attributes. Through analysis, it is concluded that the reservoir recognition method based on the seismic attribute often need more attributes combined, and establish various models to validate. On the other hand, the inversion method based on model can be used for lithologic reservoir exploration and prediction.