基于S变换的叠前地震FVO分析方法研究

发布时间：2018-06-10 12:22

本文选题：时频分析 + FVO　；参考：《中国地质大学(北京)》2015年硕士论文

【摘要】：地震波传播过程中的振幅、频率和相位等动力学特征会发生变化,这些变化可以用来表征地下地层的储层地质信息。叠前地震道集不仅保留了地震记录随炮检距变化的特性,还保留了大量横波信息,能为岩性辨别和流体探测提供更丰富、准确的依据。针对叠前地震属性的研究已成为储层流体探测领域的研究热点之一。时频分析技术的发展使得精确研究地震记录的频谱信息成为可能。S变换是一种变分辨率时频分析方法,并且保持了与傅立叶变换的直接关系,与频率可以直接对应。在高频段拥有较高的时间分辨率,在低频段拥有较高的频率分辨率。利用S变换分析地震数据,能很好地满足地震数据分析的要求。本文基于地震波传播过程中,经过含有流体的地层后,频率随炮检距变化的现象,以及地层对地震信号频率响应的影响,研究了基于叠前地震道集的FVO(Frequency Versus Offset)分析方法。FVO分析方法主要包括FVO正演方法,即利用不同储层岩性模型的FVO响应,建立区分不同流体的FVO检测标志;以及FVO储层反演方法,即利用S变换提取实际地震记录中的FVO响应,以此估算地层岩体的地震参数,进行油气藏描述。本论文利用三层水平模型进行正演,得到含气和含水储层FVO检测标志;利用S变换提取分角度叠加的叠前地震道集频率衰减梯度,结合不同流体FVO检测标志进行储层预测。通过理论验证和实际资料验证了FVO分析方法进行储层预测的可行性。
[Abstract]:The amplitude, frequency and phase of seismic wave will change in the process of seismic wave propagation. These changes can be used to represent the reservoir geological information of underground strata. The prestack seismic gathers not only retain the characteristics of seismic records varying with offset, but also retain a large amount of S-wave information, which can provide a richer and more accurate basis for lithologic discrimination and fluid detection. The study of prestack seismic attributes has become one of the hotspots in the field of reservoir fluid exploration. With the development of time-frequency analysis technology, it is possible to study the spectrum information of seismic records accurately. S transform is a variable resolution time-frequency analysis method, and it maintains the direct relation with Fourier transform and can correspond to frequency directly. It has higher time resolution in high frequency band and higher frequency resolution in low frequency band. Using S transform to analyze seismic data can well meet the requirements of seismic data analysis. This paper is based on the phenomenon that the frequency varies with the offset during the seismic wave propagation, and the influence of the formation on the frequency response of the seismic signal. The FVO analysis method based on prestack seismic gather is studied. The FVO analysis method mainly includes the FVO forward modeling method, that is, using the FVO response of different reservoir lithologic models to establish the FVO detection mark to distinguish different fluids, and the FVO reservoir inversion method. The S-transform is used to extract the FVO response from the actual seismic records to estimate the seismic parameters of the strata and rock mass and to describe the oil and gas reservoirs. In this paper, the FVO detection mark of gas-bearing and water-bearing reservoirs is obtained by using the three-layer horizontal model, and the frequency attenuation gradient of prestack seismic gather is extracted by S transform, and the reservoir prediction is carried out by combining the FVO detection criteria of different fluids. The feasibility of FVO analysis method for reservoir prediction is verified by theoretical verification and practical data.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.4

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