382 ILLINOIS STATE ACADEMY OF SCIENCE 



and Stephenson, most of DeKalb with adjoining por- 

 tions of Ogle, Lee, LaSalle, and Kendall counties on 

 the east, and parts of JoDaviess, Carroll, Whiteside, Lee, 

 and Bureau counties on the west of an area along the 

 axis of the LaSalle uplift and other minor folds. 



(4) The central area last mentioned along the axis 

 of the LaSalle uplift in the north of the State must be 

 considered as very improbable, and is so graded because 

 even the Trenton is absent here or very thin and no oil 

 has ever been found geologically below it. This area 

 includes the adjoining parts of JoDaviess, Stephenson, 

 Carroll, and Ogle, the central part of Lee, and small parts 

 of Bureau and LaSalle counties. 



THE ANALYSIS OF RESULTS OBTAINED IN TESTING THE AREA 



REGARDED AS HAVING BEST POSSIBILITIES PROJECTED 



AS A FORECAST FOR FUTURE SUCCESS 



The areas of the northward extension of the LaSalle 

 anticlinal uplift have very few outcrops, and little or no 

 testing has been done in the areas of greater promise. 

 (Figs. 2 and 3.) Although these areas have potential 

 possibilities of production from one or two horizons, no 

 definite percentage of success to be expected in test drill- 

 ing can be suggested. 



The results obtained in the remainder of the area of 

 best possibilities are given in the following table : 



