根据一个地震剖面构制地下反射层剖面叫做偏移。在地球上,许多地方地下是由水平的沉积岩石组成的。在这样的地方,地震资料的偏移可能极为简单,因为波垂直传播到反射层有与深度成正比的回声反射旅行时,所以偏移只是将比例系数乘时间轴。这样,实际上可以把能够表示Z=0处的P(x,t)的波形图(如图1)作为一个地下的剖面,比如说P(x,z/2υ)剖面。 According to a seismic section structure of the underground reflector section called offset. On earth, in many places the ground is composed of horizontal sedimentary rocks. In such places, the offset of seismic data can be extremely simple because the wave propagates vertically to depth-proportional echo echo reflections traveling vertically, so the offset simply multiplies the scale factor by the time axis. In this way, the waveform diagram P (x, t) that can represent P (x, t) at Z = 0 can actually be taken as a subsurface section, such as P (x, z / 2υ).