Elastic wave propagation in a two-layer section has been studied with a solid two-bed model and records resembling seismograms obtained for the four possible source-detector configurations. Numerous events are identified. Among these, the shear waves are found to be surprisingly prominent. The amplitude of the ground roll falls off approximately as (distance) (super -1) 2/. This is the amplitude-range dependence expected for a surface wave. The ability of two in-line detectors to reduce surface waves has been demonstrated.