Konstruktive Darstellung Von Seismischen Horizonten Unter Berocksichtigung Der Strahlenbrechung Im Raum*

The paper describes a geometrical construction which allows the reflecting or refracting Tsoundaries to be derived from seismic time observations. In reflection work the construction makes use of the ray reflected from the boundary at normal incidence. For constant velocities of the beds, or for a linear increase of velocity with depth, the method leads to the construction of successive envelopes from which the reflecting interface and the rays are obtained. By using the idea of “stretching fictitious rays”, the construction requires ruler and compasses only and is applicable to both plane and curved boundaries with any strike direction and in any number. The same principles can be applied to refraction problems and again the. construction of successive envelopes allows the indirect or Mintrop wave to be defined. The position of the refracting boundary and the velocity can be derived immediately. As in the reflection method any number of plane boundaries with any strike can be dealt with. An appendix discusses the use of the method in reflection work with any type of velocity distribution.