SEISMOLOGICAL DISCOVERY AND PARTIAL DETAIL OF 
VERMILION BAY SALT DOME, LOUISIANA! 
E. E. ROSAIRE? and O. C. LESTER, JR: 
Houston, Texas 
ABSTRACT 
The Vermilion Bay salt dome in Iberia Parish, Louisiana, was one of the first 
discovered by a geophysical survey of water-covered areas. The field organization and 
equipment of such a crew is described. The discovery and detail data are presented, 
along with the original interpretation of these data. The results of drilling are shown, 
and the agreement and disagreement of these tests with the original interpretations 
discussed to some extent. 
LOCATION 
Vermilion Bay is one of the major features of the Louisiana coast 
line. The Vermilion Bay salt dome is located in the southeastern 
corner of the bay, but in the extreme southern portion of Iberia 
Parish, Louisiana. It is best reached by boat along the Boston Canal 
from Abbeville, or by car to Cypremort Point, and thence by boat to 
the dome. 
DISCOVERY 
This salt dome was discovered on September 25, 1927, in a recon- 
naissance refraction exploration conducted for the Louisiana Land 
and Exploration Company by a Geophysical Research Corporation 
party* under the direction of the junior writer. 
The discovery of this dome was of importance beyond the usual, 
for several reasons. Among these may be listed the following. 
1. This salt dome was discovered as a result of the use of the 
seismograph in exploring large bodies of water. The Louisiana Land 
and Exploration Company was the first to launch a major exploration 
campaign with this definitely in view, using for this purpose two Geo- 
physical Research Corporation parties, equipped for water surveys. 
1 Read before the Association at the Oklahoma City meeting, March 25, 1932. 
Published by permission of the Louisiana Land and Exploration Company, and the 
Geophysicaf Research Corporation. 
2 Consulting geophysicist, 2210 Esperson Building. 
3 Geophysical Research Corporation. 
‘ Within a month, this same crew had also discovered the Four Isle and Dog Lake 
salt domes, in southwest Terrebonne Parish. 
5 The other crew, under the direction of C. G. Rosaire, was the first to discover a 
salt dome during a water survey, since his discovery of the Calcasieu Lake salt dome 
antedated O. C. Lester’s discovery of the Vermilion Bay dome by several days. 
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