I demonstrate a simple, robust method for estimating wavetype polarization directions at a single geophone. The results appear to be repeatable to within about half a degree. The wavetype polarization directions in turn provide information about the position of the source. Knowing that the source motions derived from both P and S arrivals should be the same gives us further information about the source radiation patterns. The main effect seems to be that the first stomp at a given location is weaker than all later ones.
Careful design is sufficient in the case of seismometers.
Sources are another matter, since they interact in an unknown, variable, and non-linear manner with the earth's surface. We discuss a technique and requirements for reducing the responses of multi-component sources to a uniform isotropy. We explain the problem structure and find a pre-stack formulation which minimizes the differences in a reciprocal trace pair. The measured quantities in nine-component seismic data recorded at a free surface are displacements in the X, Y, and Z directions. The quantities we would like to use in seismic imaging are the amplitudes of the upcoming P, S1 and S2 waves.