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反射波法地震勘探是以激发弹性振动和记录振动从地质体界面的反射作为基础的。反射波的强度主要取决于相邻介质物性的(主要是岩石的密度)差异程度和界面的清晰程度。该方法的精度和分辨力则由地震波的波长而定。后者不仅以振动源而且也以介质的性质为转移,因为速度随着深度而增大,弹性振动频率随深度而减低。在沉积盖层的上部振动频率可能达到100多 Hz(波长是几米和几十米),而在3km 多的深度上几乎没有记录到高于40Hz(波长一般为几百米)频率的振动。据认为,该方法的分辨力大约为1/4波长,但是,在最
Reflected wave seismic exploration is based on the excitation of elastic vibrations and the reflection of seismic vibrations from the geological body interface. The intensity of the reflected wave mainly depends on the degree of difference (mainly the density of the rock) and the clarity of the interface between adjacent media. The accuracy and resolution of the method depend on the wavelength of the seismic wave. The latter shifts not only with the source of vibration but also with the properties of the medium as the velocity increases with depth and the frequency of elastic vibrations decreases with depth. Vibration frequencies above the deposition cap may reach over 100 Hz (wavelengths are a few meters and tens of meters), whereas very little vibration above 40 Hz (typically a few hundred meters in wavelength) is recorded at depths of more than 3 km. It is believed that the resolution of this method is about 1/4 wavelength, however, at the most