根据波动方程正演模拟的基本原理，模拟某矿的地质条件，建立以实际地层速度为基础的深度域层速度模型，在该地质模型中共设计了6个直径为15～120 m、高度不等、影响层位不同的陷落柱。通过对正演合成记录的叠前、叠后数据处理得到的正演剖面进行分析，发现陷落柱在模型正演叠加剖面均表现绕射波发育，在叠加和偏移剖面上表现为反射能量变弱，同相轴扭曲或中断，相位发生变化，叠前深度偏移技术更有利埋藏较深、高度较小的偏移成像。通过实际地震数据和模型正演数据的对比分析，有助于在地震剖面上识别陷落柱等复杂地质体以及验证地震解释成果的正确性。%According to basic principle of wave equation forward modeling to simulate geological condition of a coalmine, established an actual stratigraphic velocity based depth domain interval velocity model. In this geological model designed 6 subsided columns with diameter 15~120m, different heights and impacting horizons. Through analysis of forward section from forward synthetic record prestack, poststack data processing have found that subsided columns on model forward stacked section all appear as diffracted wave developed, on stacked and migrated sections appear as reflected energy weak, phase axis distorted or interrupted, phase changed. Prestack depth migration technique is more propitious to deeper buried, smaller height target migration imaging. Examples have shown that through contrastive analysis of practical seismic data and forward model data, help to identify subsided column and other complex geologic body on seismic section, as well as verify correctness of seismic interpretation.
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