地震数据叠前偏移成像及其在浅层地震勘探中的应用研究

PRESTACK DEPTH MIGRATION IMAGING OF SEISMIC DATA AND ITS APPLICATION TO SHALLOW SEISMIC PROSPECTING

文中讨论了在浅层地震勘探中地质结构和构造的复杂性以及对浅层地震勘探成果要求精度较高的特殊性,指出了在浅层地震勘探中发展叠前深度偏移的重要性,并对相移法叠前深度偏移的基本原理和实现方法进行了详细论述,编制了相应的软件。通过使用该方法对 2种理论试验模型进行试算,获得的深度偏移剖面层位清晰,构造明显,较准确地体现了理论模型地质结构和构造的特征,效果良好。然后又使用实际浅层地震反射资料进行了叠前偏移计算,所得结果与已知地质结构和构造相吻合,也取得了较好的结果,证实了该方法及软件的可靠性和实用性,可用于实际浅层地震反射勘探资料的叠前深度偏移处理。

This paper describes the complexity of geological structures and tectonic features in shallow seismic prospecting, as well as the particularity of higher accuracy requirement for its achievements. It is suggested that it should be very important to develop prestack depth migration method for shallow seismic prospecting. The basic principle of prestack depth migration with phase shift method and its algorithm are also expounded in detail, and the relevant PC program is compiled. Based on this method, two theoretic models are tested, and good results are obtained. The results show that the stratigraphic horizons are displayed clearly in the prestack depth migration sections, and the characteristics of geological structure and tectonic features of the theoretic models are expressed fairly well. Furthermore, the method has been applied to process the actual shallow seismic reflection data, and the obtained results are identical with the known geologic structures and tectonic features. All these results demonstrate the reliability and applicability of this algorithm and its software. It is clear that the prestack depth migration method can be effectively used in the processing of actual shallow seismic reflection data.