利用三维地震解释技术识别煤田陷落柱

Coalfield Subsided Column and Gob Area Identification through 3D Seismic Interpretation

三维地震资料能够识别的陷落柱大小与三维地震横向分辨率密切相关,在三维数据体中,三维偏移剖面的最佳水平分辨率取决于反射界面的平均速度及零相位子波的中心频率。为验证三维地震资料分辨陷落柱最小直径的能力,设计了9个直径从30 m到100 m不等、影响深度不同的陷落柱模型,其波动方程正演结果表明:陷落柱直径大小、垮塌高度都对地震反射波产生影响,进而影响到地震解释陷落柱的精度;陷落柱的直径与垮塌高度越大,则其在地震剖面上的反映越明显,反之则不易识别。并通过煤矿采区三维地震勘探技术应用实例,展示了常规三维地震解释技术结合方差、曲率等多属性综合分析技术在识别煤层陷落柱的有效性。

The magnitude of subsided column can be identified through 3D seismic data is closely related to 3D seismic transverse resolution. In 3D data volume, the optimum horizontal resolution of 3D migration section rests with reflecting interface average velocity and zero phase wavelet center frequency. To validate capacity of 3D seismic data differentiate subsided column minimum diameter, have designed 9 subsided columns with different diameters from 30m to 100m, and different impacting depths. The wave equation forward results have shown that the size （diameter） of subsided column and collapsed height will impact seismic reflection, and then impact subsided column seismic interpreted accuracy. The larger subsided column diameter and collapsed height, will produced the more obvious image on seismic section;on the contrary, not easy to identify. Through coalmine winning district 3D seismic prospecting case studies, have illustrated the effectiveness of conventional 3D seismic interpretation technology combined with multi-attribute integrated analytical technology including variance, curvature etc. in coal seam subsided column identification.