950 



EXPLORATION GEOPHYSICS 



and passes through Sections 27 and 34 of T. 1 N.-R. 13 E., then through 

 Sections 2, 3, 10, 9, 8, 5, and 6 of T. 10 N., R. 10 W., and continues 

 through Sections 1 and 2 of T. 10 N., R. 11 W. and into Section 33, T. 1 N., 

 R. 12 E. The survey was not extended sufficiently to the north and north- 

 west to determine the edges of the anomaly in these directions. An inter- 

 esting feature of these data is the band of extremely high hydrocarbon 

 concentrations which covers most of Section 36, T. 1 N., R. 12 E. and 

 part of Section 31, T. 1 N., R. 13 E. This band of high values separates the 

 main anomaly into two sub-anomalies. 



Fig. 584. — Geochemical survey of the Heidelberg Area, Jasper County, Mississippi. Well symbols 

 show field development at start of survey, May 28, 1944. (Horvitz, Geophysics, October, 1945.) 



Outside of the anomalous area are occasional values which are higher 

 than the background values (below 50 parts per billion). Of 25 such 

 values, 15 are in the first contour interval (50-99 parts per billion) ; five 

 are in the next higher interval (100-199) ; four are in the third interval 

 (200-399) ; and one is in the highest interval. Of significance is the fact 

 that only 15% of the values in the background area attained 50 parts per 

 billion or more, while in the anomalous area, 38% of the values are 50 parts 

 per billion or more. Of the 16 extremely high values (800 parts per billion 

 and above) , only one is outside of the anomalous area. 



