【摘要】 影响波动方程叠前深度偏移成像精度的主要因素除了要求勘探区覆盖次数均匀、单炮记录信噪比高外,还必须建立准确的偏移速度场及选择合适的偏移孔径,其中速度深度模型的建立原则取决于偏移后共反射点道集同相轴是否呈水平形态,而偏移孔径的选择依据则是目的层倾角的大小。在地层倾角变化剧烈的吉新煤矿区,深度域层速度场采用三次速度迭代求得,并确定偏移孔径为600m×600m。应用表明:叠前深度偏移比叠后时间偏移处理在复杂构造区成像准确、断点空间位置清晰,且在解决复杂地质构造成像问题的同时还能够提高资料的信噪比和分辨率,是解决复杂构造成像的有效工具。更多还原

【Abstract】 Other than even folds in prospecting area and high single-shot record S/N,the main contributing factors to impact wave equation prestack depth migration imaging precision,exact migration velocity field have to be established and suitable migration aperture selected.In which,establishing principle of the velocity depth model is dependent on if the common-reflection point-gather phase axes are horizontal,while the selection basis of migration aperture is the dip of target.In the strata dip sharply varying Jixin coalmine area,using velocity iteration three to obtain depth domain horizon velocity field,and has determined migration aperture 600m×600m.The practice has demonstrated that: the imaging accuracy and fault spatial limit details after prestack depth migration are better than poststack time migration in complicated structure areas.Moreover,as the same time as solving the structural imaging in complicated area,can also improve data S/N and resolution,thus an effective tool to settle complicated structure imaging.更多还原