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In this paper a method of calculating synthetic seismograms from continuous velocity logs (CVL) is presented and described in detail.The seismic velocities on the CVL are frequently and rapidly changing. Therefore a seismic field-record consists of a great number of reflections with different sign and amplitude.The sum of all reflections forms the seismogram. The first part deals with some relations between the log, the reflection-layers, and the normal field-record, with special emphasis on the influence of the seismic amplifier. Then several assumptions are made for the construction of the synthetic seismograms. Finally some examples and applications are given.

Moving source profiling is a modification of walk‐away vertical seismic profiling in which the source is moved along a line across a well while the signal is recorded in the well at a certain depth. The method was designed to better predict the target horizon below the drill bit and away from the well location. The method has several advantages in areas of complicated overburden. In overthrust regions, the receiver is placed below much of the complicated structure to minimize distortion of the reflected signal. The final seismic image is a depth presentation of the subsurface structure and stratigraphy based on wavefront calculations. This depth estimation is obtained without extensive processing of the recorded data. The final result is available within a few days and can help interpreters to decide if and where to sidetrack the well. The method is demonstrated using an example from the overthrust zone of the Lower Saxonian Basin and the Pompeckj's well in Northern Germany.