Abstract
Seismic records obtained at the same point with hole and surface charges are compared. Evidence is presented that multiple reflections from within the Edwards limestone are sufficiently prominent on the hole shot records to mask and obscure primary reflections. It is postulated that the large number of these multiples is attributable to the great amount of high frequency energy generated in the competent Edwards limestone by a hole shot.The relative lack of multiple reflections on the Poulter Method records is believed to be due largely to the fact that essentially all of the energy entering the ground is of low frequency in the part of the spectrum available for deep reflections. This nullifies the apparent high frequency selectivity effect of the Edwards limestone.
