Some experiments are described which demonstrate the occurrence of an initial reflection from above shot level and of a resultant secondary reflection from depth which, by optical analogy, may be termed a ghost reflection. The reflector above shot level was in this case the base of the weathered layer. Reflection coefficients as high as 2/3 were found in the Pleistocene Beaumont clay surface in Harris County, Texas. With reflection coefficients of this magnitude, the ghost reflections influence the character of seismograms noticeably.
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