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反射地震数据可通过偏移共中心点倾斜迭加剖面成像。其基本方法就是对相同射线参数的各共中心道倾斜迭加剖面合成。早期研究人员已经描述过倾斜迭加炮平面或取代共中心点道集的共接收器道集的偏移方法,但是,共中心点倾斜迭加具有中心点坐标的实用的优点。除此之外,偏移方程未对陡倾角、宽偏移距或垂向速度变化作任何假设。本方法理论上的缺陷在于没有对横向速度变化进行精确处理。倾斜迭加偏移是一种“迭加前的偏移”方法,它可解决常规迭加存在的问题(特别是当水平反射层与陡倾角反射层相交时的倾角选择性问题)。在图象上,所有倾角的正确处理可提高横向分辨力。在偏移改善地震资料以后,倾斜迭加偏移可提供一种测定层速度的简单方法。对超临界反射和折射运用倾斜迭加偏移的旅行时间处理方法也是准确可行的。这些同相轴与中心点的附加度量转换成p-t面。倾斜迭加偏移方程将p-t面转换成一个深度-共中心点速度面。与通常的偏移一样,在速度的反演过程中自动考虑了倾角影响。
Reflected seismic data can be imaged by offsetting co-centered tilt-superimposed sections. The basic method is to synthesize the profiles of the concentric channels with the same radiance parameters. Earlier researchers have described a method of offsetting co-receiver gathers of slant-superimposed cannon planes or replacing a common-center gating set, however, common-center tilting has the practical advantage of center-point coordinates. In addition, the offset equation does not make any assumptions about steep dip, wide offset, or vertical velocity variations. The theoretical disadvantage of this method is that it does not handle the lateral velocity changes accurately. Tilt stack offset is a “pre-stack offset” method that addresses the problems of conventional stacking (especially the tilt selectivity when the horizontal reflector intersects the steep reflector). On the image, correct handling of all inclinations improves lateral resolution. Tilt-offset migration provides a simple way to measure the velocity of the layer after offsetting the seismic data. It is also accurate and feasible to use the travel time processing method of superposition reflection and refraction with oblique superposition offset. The additional measures of these events and center points translate into p-t planes. The tilt-plus-offset equation converts the p-t plane into a depth-common-center velocity plane. As with normal offsets, the effect of dip angle is automatically taken into account in the velocity inversion.