CALDWELL COUNTY. TEXAS 

 S.P RES. VEL. 



GONZALES COUNTY. TEXAS 

 S.P RES. VEL. 



Figure 21-6. Comparison of velocity logs and electrical logs, Texas. 



velocity logs with elecrical and radioactive curves and show excellent examples 

 in their paper published in 1956. 



Another velocity log-electrical log comparison shown in Figure 21-7 

 illustrates how the velocity log may supplement the electrical logs in correlation 

 studies. The Woodford-Hunton-Sylvan-Viola sequence persists over central 

 Oklahoma. A velocity log taken from the files may be identified as an Oklahoma 

 log by examining the recorded velocities in this part of the log, almost as easily 

 as by reading the location from the log heading. The geologist sitting on the 

 well in which these logs were run had no diffculty picking the top of the Hunton 

 from samples, but the electrical curves alone do not indicate this interface with 

 certainty. 



VELOCITY LOG 



13000 FPS 25000 



CENTRAL OKLAHOMA 



S.P. RESISTIVITY 



Figure 21-7. Comparison of velocity, SP., and resistivity curves, central Oklahoma. 



415 



