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与纯模式处理相比,转换波处理对与岩石速度有关的物理假定的依赖性更大,因为成像点的时差和偏移距都取决于介质的物理参数。因此,介质均匀性和各向同性的不真实假定比波的纯模式传播影响也就更大(在后一种情况下,成像点偏移距是用几何方法而不是物理方法确定的)。在层状各向异性介质中,转换点的偏移主要受有效速度比γ_(eff)≡γ_2~2/γ_0(式中γ_0≡(?)_p/(?)_s为平均垂向速度比;γ_2是相应的短排列时差速度比)控制。如果在相应的反射同相轴之间建立起近似的相关关系,这些比值便可根据P波和转换波数据求得。若简单地根据γ_0而不是γ_(eff)进行采集设计,那么就会导致不甚理想的数据。适用于均匀各向同性介质算法的计算机程序也能勉强用来处理层状各向异性介质,在把γ_(eff)作为速度比函数的情况下,有时精度较高。然而,简单的闭形公式允许进行双曲线校正和剩余校正以及转换点偏移计算,而没有这些约束性假定。在这些方程式中,把垂直脓行时作为独立变量更好(相对于深度),因为在出现极性各向异性的情况下,深度的确定不够精确,可放到处理流程的后期解决。如果地下介质显示横向变化和/或方位各向异性,那么在互换震源和检波器位置时,转换波数据就不会是一成不变的,因此一个中间放炮排列的道集就会出现不对称的
The conversion wave processing is more dependent on the physical assumptions associated with rock velocity than pure mode processing because the time lag and offset of the imaging points depend on the physical parameters of the medium. Therefore, the unrealistic assumptions of medium homogeneity and isotropy have more influence than pure mode propagation of waves (in the latter case, the image point offset is determined geometrically rather than physically). In layered anisotropic media, the shift of the shift point is mainly affected by the effective speed ratio γ eff (γγ 2 ~ 2 / γ_0 (where γ_0≡ (?) _p / (?) _s is the average vertical velocity ratio; γ_2 is the corresponding shortest alignment speed ratio) control. If an approximate correlation is established between the corresponding reflected events, the ratios can be found from P-wave and converted-wave data. Simply collecting the design based on γ_0 instead of γ_effff will result in less than ideal data. Computer programs that are suitable for homogeneous isotropic media algorithms can barely be used to deal with layered anisotropic media, and sometimes have high accuracy with γ eff as a function of speed ratio. However, a simple closed-form formula allows hyperbolic and residual correction and shift point offset calculations without these binding assumptions. In these equations, vertical pushes are better independent (relative to depth) as independent variables because the depth is not accurately defined in the case of polar anisotropy and can be addressed later in the process. If the subterranean media shows lateral and / or azimuthal anisotropy, the converted wave data will not be static when the source and receiver positions are swapped, so an asymmetrical