Interferometric full-waveform inversion
Interferometric full-waveform inversion
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DOI：
10.1190/geo2018-0047.1
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发表时间：
2019
期刊：
影响因子：
3.3
通讯作者：
Mrinal Sinha;G. Schuster
中科院分区：
文献类型：
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作者：
Mrinal Sinha;G. Schuster
速度模型浅层的速度误差会导致全波形反演（FWI）断层图像的错误估计。如果反射体的位置和地形是已知的，则这样的反射体可以用作参考反射体以更新底层速度模型。对应于该参考反射器的反射在数据空间中被加窗。然后，窗口化的参考反射与来自更深界面的反射互相关，这导致由参考界面上方的覆盖层引起的静态误差的部分抵消。然后使用干涉FWI（IFWI）来反转目标区域中的断层图像，通过最小化观察到的和预测的互相关图之间的归一化波形失配。与静态误差以上的参考接口的合成和现场数据的结果表明，一个准确的断层图像可以被反转的参考接口的几个波长内的区域。IFWI也可以应用于合成时间推移数据，以减轻随时间变化的覆盖层变化所造成的非重复性误差。合成和现场数据的例子表明，IFWI可以提供准确的层析成像时，近地表是骑与速度误差。
Velocity errors in the shallow part of the velocity model can lead to erroneous estimates of the full-waveform inversion (FWI) tomogram. If the location and topography of a reflector are known, then such a reflector can be used as a reference reflector to update the underlying velocity model. Reflections corresponding to this reference reflector are windowed in the data space. Windowed reference reflections are then crosscorrelated with reflections from deeper interfaces, which leads to partial cancellation of static errors caused by the overburden above the reference interface. Interferometric FWI (IFWI) is then used to invert the tomogram in the target region, by minimizing the normalized waveform misfit between the observed and predicted crosscorrelograms. Results with synthetic and field data with static errors above the reference interface indicate that an accurate tomogram can be inverted in areas lying within several wavelengths of the reference interface. IFWI can also be applied to synthetic time-lapse data to mitigate the nonrepeatability errors caused by time-varying overburden variations. The synthetic- and field-data examples demonstrate that IFWI can provide accurate tomograms when the near surface is ridden with velocity errors.