148 F. GOLDSTONE 
flexions from lenticular beds, and in the particular case of the Gulf 
Coastal Plain of Texas and Louisiana these reflexions frequently per- 
sist and are correlatable over distances in excess of 1,000 feet. 
ed Ss “ 
AIA, 


20 
iS 
° R2W 
Fic. 8.—Lucien area, Noble County, Oklahoma. Contoured on Viola limestone data 
obtained by reflexion shooting. 
Figure 10 (a) to (c) shows examples of typical seismograms ob- 
tained under such conditions. 
Figure 10 (a). The shot point in this instance is located down dip 
from the seismometers as evidenced by the fact that the reflected 
energy is arriving almost parallel to the surface; in fact the last event 
indicated with an arrow on the record reaches the most remote seis- 
mometer ahead of the nearer seismometers. In this instance the shot 
808 
