50 TL AEE, 
REASON FOR POOR ENERGY-CARRYING CHARACTER 
The reason for poor energy transmission is probably due to al- 
ternating beds of hard and soft material, perhaps sandstones and 
clays. There is an area in the Gulf Coast where a poor energy-carrying 
horizon is found, and it is especially noticeable in Harris County, 
Texas. The movement on the seismogram is a small wave whose be- 
ginning is scarcely perceptible and is sometimes mistaken for a salt 
dome “‘forerunner.’”’? Recent work by the reflection method in the 
Gulf Coast region shows several reflections from the horizon which 
transmits the refracted wave poorly, indicating a change in density 
which would logically be explained by alternating beds. If the al- 
ternating beds which compose the acoustic horizon had slightly 
different velocity values, the refracted wave would gain a slight 
amount in the faster bed, and be gradually damped out. 
CONCLUSION 
The seismic wave accurately shows the subsurface conditions. The 
character of the wave is affected by the various strata through which 
it passes, and a study of the wave character is important in the cor- 
rect interpretation of seismic results. The possibilities of the seismo- 
graph as an accurate exploratory instrument have not been fully 
realized, and this paper is presented with the hope that further study 
along similar lines will broaden the scope of usefulness for this in 
strument. 
380 
