【摘要】 勘探初期,工区内钻井较少和砂体厚度较小且横向分布不稳定的时候,找到一种合适的方法来描述砂体的分布范围和厚度是一件十分困难的事情。地震的各种属性和波阻抗反演在碳氢检测、储层预测和层序地层解释中具有广泛的应用,基于属性的地震相分析可以清晰地刻画砂体的横向分布情况。研究区调谐频率和砂体的厚度有较好的对应关系,因此,根据实际情况,在充分了解研究区沉积背景的前提下,首先,优选提取可以识别砂体范围的各种地震属性,利用基于多属性的地震相分析描述出砂体的分布范围;其次,根据时频分析做谱分解,计算出一个频率域的数据体,提出每道能量最大处的频率值,得到最大频率平面图;然后,根据高分辨的波阻抗反演剖面和研究区的唯一一口钻井,建立砂体厚度和频率的拟合关系式;最后,用统计的拟合关系式,推算出整个研究区砂体分布范围内的厚度平面图。实际应用结果表明,该方法能较好地预测砂体分布范围和厚度。更多还原

【Abstract】 In the initial stage of exploration,when there are a few wells drilled in work area,and the sand bodies are very thin and unstable in lateral distribution,it is difficult to find a good way to predict them.Various seismic attributes and wave impedance inversion have been applied widely in hydrocarbon detection,reservoir prediction and sequence stratigraphy explaination,which can clearly describe the distribution of sand bodies horizontally based on the seismic facies analysis.Wave impedance can describe the thickness of sand bodies vertically,while tuning frequency has a better corresponding relation with the thickness of sand bodies.In this paper,firstly,we predicted the distribution of the sand bodies,which were mostly obtained through the research of sedimentary environment and the analysis of seismic facies based on multi-attribute;secondly,we computed a data volume in frequency domain after making spectral decomposition to raw seismic data through time-frequency analysis,and then extracted the time of maximal amplitude each trace in the data volume,getting a planar graph of the peak frequency;thirdly,we built the fitted formula between the peak frequency and the thickness of sand bodies using the wave impedance inversion profile after high resolution processing and the unique drilling well in research area;finally,we used the fitted formula to compute the distribution map of the thickness of all sand bodies in whole research area through the thin layer tuning principle which was put forward by Widess.The practical application shows that the method can predict the the distribution and thickness of sand bodies well.更多还原