>[irHTr.A\ ArVOKMY Ol" SrlKNCK. 



89 



If a line A. . . .13 he used lo represent llie state line from 8ylvania_, 

 Ohioj eastward into Lake Erie; and a eurved line C....D the surface 

 of the Trenton — for example; and K. . . .F the Potter well^ 1,5''>5 feet 

 to and 112 feet into the Trenton in Erie Townsliip, Monroe County, 

 Michigan ; then it is shown how, located as it is, that well penetrated 

 only the upper or outer strata of the Trenton and trends away from tiie 

 jiossible reservoir of tlie arch of the anticline, the angle at G being 

 obtuse. 



Figure 3. Diagram of geological conditions uitli i-ftVreiice to oil wells sunk in 

 the region studied. 



To penetrate the Trenton strata directly from point V] the drill siiould 

 follow the line E. . . .H to take the Trenton surface at riglit angles at 

 K, and penetrate the depth of possible supply : the logical meaning of 

 which is a well at L, (in relation to point E) and preferably at some 

 point along the line L . . . . B, on the west shoulder of the anticline, or 

 along L. . . .B projected, on the east shoulder. The line E. . . .F, how- 

 ever, illustrates the relative position of each and every well that has 

 been put down in search of oil on the Michigan side of the field and, in 

 a less degree only, on the Ontario side of it. None but lateral tests 

 have been made, and most of these remote. 



Unfortunately the only land surfaces within the enclosed area are the 

 Sister Islands, East, Middle and West, North Harbor, the Hen and 

 Chicken Islands, and the associated banks and shoals. 



EXAMINATION OF THE FIELD BY CROSS SECTION. 



A Ballards Reef east and west section of the northern part of the 

 field under review would show these surface extensions in order, west- 

 ward of the reef: Lower Monroe for a short distance; Sj'lvania sand- 

 stone over at least a part of Grosse Isle ; L^pper Monroe on westward 

 part of Grosse Isle, throughout its entire length and over nearly all the 

 Trenton Channel of Detroit River ; Anderdon limestone beds all about 

 the outer edge of the Sibley quarry area from about the River Road 

 westward, probably reaching the west bank of the Trenton Channel, 

 opposite the Church Company's dairy barn well, and possibly reaching 



