基于变差函数的高精度静校正融合技术及其应用

Research and application of high-precision merged static correction technology based on variogram

地震反射波时距曲线受复杂地表地质结构的影响产生畸变而不能同相叠加,需要对地震资料做静校正处理。不同的静校正方法都有各自的适用条件:高程静校正无法消除低降速带的影响;模型静校正受限于追踪的深度和排列的长度,难以全面反映低速带底界的形态;折射静校正仅适用于地表较平缓、表层速度横向均匀性较好且有明显折射界面的地区;层析静校正适应任意表层模型的反演,但是反演结果不稳定。在地震勘探地区地貌日益复杂的今天,优选的某一种静校正方法无法有效解决所有的问题。鉴于上述问题,提出了一种适用于多种地表类型复杂区域地震资料处理的基于变差函数拟合重构的高精度三维静校正方法,该方法能够实现不同静校正量的拟合和重构,并很好地解决复杂地表条件下不同静校正方法优势拟合的难题,从而可有效提高复杂地表地形条件的三维地震资料的成像质量,保证构造形态的可靠性。

The travel-time curve of seismic refraction waves is distorted by complex suriace geological structures and cannot in-phase stack, so we need to carry out static correction of seismic data. Each static correction method has its own application condition： the elevation statics method cannot eliminate the effect of low velocity; the model statics method is limited by the length of alignment and the depth of tracking, so it is difficult to fully reflect the form of low- velocity zone bottom boundary; the refraction statics method is only applied for areas with flat surface, uniform lateral velocity and significant refractive layers ;the tomography statics method is adapted to any surface model inversion, but the inversion results are instability. A certain kind of static correction cannot solve all problems for increasingly complex exploration areas. This paper presented a high-precision three-dimensional static correction method based on variogram fitting reconstruction which is applicable achieve fitting and reconstruction of different statics, solve to complex region with a variety of surface types, it can the problem of different static correction advantage fitting in the complex surface conditions, and effectively improve the image quality of three-dimensional seismic data to ensure the reliability of structural morphology.