基于波动方程的共聚焦点成像技术

Common focus-point imaging based on wave equation.

对于较复杂的理论模型和低信噪比的实际地震资料处理来说,用基于射线理论的有限差分走时法共聚焦点(CFP)成像技术生成的CFP偏移剖面不能精确地对地下构造成像。为此,探讨了基于波动方程的傅里叶有限差分法(FFD)共聚焦点(CFP)成像技术。该技术可以自动检测宏观速度场正确与否,大大提高了聚焦算子的计算精度和双聚型保幅成像精度。数值模拟验证了方法的正确性,实际资料处理验证了方法的有效性和实用性。与基于射线理论的有限差分走时法的CFP成像剖面对比结果表明,基于波动方程的CFP偏移剖面分辨率更高,层位更清楚,可以对地下构造清晰成像。

The common focus-point(CFP)imaging technology utilizes ray-theory-based finite difference travel-time method.In complex theoretical model and actual low S/N seismic data processing,the generated CFP imaging profiles can not exactly image the subsur- face structures.Therefore,the CFP using the wave-equation-based Fourier finite difference method is discussed.This technology can automatically detect the correctness of veloehy field,which greatly improves the computation accuracy of focusing operator and the ac- curacy of bifocal amplitude-preserving imaging.Numerical simula- tion has verified the correctness of the method and actual data pro- eessing has proved its validity and practicability.Compared to the ray-theory-based CFP imaging profiles,the wave-equation-based CFP profiles have higher resolution and clearer stratigraphie horizons, which can clearly image the subsurface structures.