宽方位角在煤田三维地震勘探中的研究与应用

从理论角度分析了宽方位角观测系统方位角、偏移距及满覆盖次数分布等特点，以地质构造发育、各向异性显著的鄂尔多斯盆地西缘的萌城矿区某勘查区为例，对宽、窄方位角观测系统的勘探成果进行对比分析。结果表明：相对于窄方位角观测系统，宽方位角观测系统1次覆盖向满覆盖过渡快，野外数据采集时对地表障碍物变形观测易于实现；宽方位角观测系统大大提高了横向上的观测能力，有效扩展了观测方位角，使获得的地震数据更趋于全息三维，方位角分布更均匀；在数据处理过程中，应注重进行子波保真、远道动校正及速度分析，便于获得分辨率较高、构造成像清晰的地震数据；相对于窄方位角地震勘探，宽方位角地震勘探观测通常覆盖次数更高，但勘探成本较高。

Research and Application of the Wide Azimuth in 3D Seismic Exploration

The characteristics of the azimuth angle，offset and full coverage number distribution about the wide azimuth observation system is analyzed from the perspective of theory.Taking the prospecting area of Mengcheng mining area which is located in the west margin of Ordos basin as an example,the geological structure of prospecting area is developed and the anisotropy of the prospecting area is significant.The exploration results between the wide and narrow azimuth observation system are compared.The results show that,compared with the narrow azimuth observation system,the wide azimuth observation system could make the transition from single coverage to full coverage more faster,the deformation observation of surface barriers can be conducted in the process of field data acquisition.The lateral observation ablity is imprved greatly and the observation azimuth is extended by the wide azimuth observation system,so,the seismic data obtained by the wide azimuth observation system tend to be more holographic 3D,and the azimuth distribution is more uniform.In the process of data processing,more attention should paid to the way of wavelet fidelity,far trace NMO and velocity analysis so as to obtaine the more high resolution and more clear seismic data.Compared with the narrow azimuth seismic exploration,the cover number of wide azimuth seismic exploration is more higher,however,its exloration cost is become higher accordingly.