APPLICATIONS OF DIP SHOOTING 121 
In justice to the investigators and their sponsors, the writers feel 
that some attention must be called to the fact that many scientists 
holding responsible positions in companies sponsoring major geo- 
physical programs, refused flatly to admit that the method was based 
on fact. As one who personally tried to introduce the method into 
general consulting practice, the senior writer can definitely recall 
many times when reflections were not even considered on a par with 
the divining rod, for at least that device had a background of tradition. 
DIP METHODS 
In 1920, with the end of refraction explorations in sight, Eugene 
McDermott, then of the Geophysical Research Corporation, secured 
the approval of L. P. Garrett of the Gulf Production Company, to 
try reflections in the Gulf Coast. It must be admitted that no inter- 
pretation other than that developed in Oklahoma was contemplated, 
that is, the correlation of reflections from supposedly consistent beds. 
Some success was secured on two producing domes, Hankamer and 
Port Barre, but the method failed at the Clodine Prospect, and one 
dry hole was credited there to attempted correlations. 
The next trial was at Darrow, then considered a very favorable 
refraction discovery which had been confirmed by the torsion balance. 
However, the area had already been investigated by two wells, both 
dry. So where even geologists walked softly, a .eflection survey was 
started. 
T. I. Harkins, in charge of the work, noticed that abnormal step- 
outs in the reflection time were rather characteristic of the area, and 
that these abnormal step-outs reversed. He correctly attributed this 
phenomenon to dipping beds, and pointed out that when recording 
up-dip the reflection arrival times for the farthest geophone should be 
abnormally short, and when recording down-dip they should be ab- 
normally long. The method was then placed on a more quantitative 
basis, and is now the recognized method for mapping the younger 
formations of the Gulf Coast. 
Since that time, the method has had some striking successes, and 
also some disappointments. However, these disappointments were 
largely the result of condemning reflection structures with single drill 
tests, which, to say the least, is somewhat rigorous. However, the 
background of success is rather satisfactory, since in several instances 
the reflection detail resulted in the location of discovery wells even 
after as many as three dry holes had supposedly condemned a pros- 
pect. On the other hand, at least three prospects have been drilled 
in spite of a condemnation by reflections, with resulting dry holes. 
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