On the limited aperture migration in two dimensions
On the limited aperture migration in two dimensions
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DOI：
10.1190/1.1444409
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发表时间：
1998-06
期刊：
影响因子：
3.3
通讯作者：
Jianguo Sun
中科院分区：
文献类型：
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作者：
Jianguo Sun
不完全数据孔径偏移是勘探地震学中的一个重要问题，因为偏移孔径的位置和大小都会影响偏移的质量。在2-D情况下，静态相位(高频)分析得出结论：有限大的偏移孔径会产生具有三个分量的偏移图像。一个来自反射射线和点绕射射线走时曲线的切点，给出偏移信号。另一些则来自偏移孔径的两个端点，并导致偏移噪声。为了在保证真振幅重建的同时消除偏移噪声，偏移孔径的位置应使其中心部分包含上述切点，并且应修改真幅值权函数以使输入数据在偏移孔径边界附近变小。此外，偏移孔径的中心部分不应小于由交界点所限定的间隔。
Migration of incomplete data aperture is an important problem in exploration seismology because both the location and the size of the migration aperture affect the quality of migration. In 2-D cases, a stationary phase (high‐frequency) analysis concludes that a finitely large migration aperture results in a migrated image with three components. One comes from the tangent point between the traveltime curves of reflected and point‐diffracted rays and gives migration signal. The others are from the two endpoints of the migration aperture and result in migration noise. To guarantee the true‐amplitude reconstruction as well as to remove the migration noise, the migration aperture should be positioned so its central part contains the tangent point mentioned above, and the true‐amplitude weight function should be modified so it tapers the input data near the boundary of the migration aperture. Also, the central part of the migration aperture should be not smaller than the interval confined by the points where th...