04 8 M. L. FULLER APPALACHIAN OIL PIELD 



mountainous regions of West Virginia, where some 6,000 feet of the shaly 

 series are probably present, but it thins rapidly toward the west. In the 

 Buckhannon quadrajigle, some 25 miles from the eastern border of the 

 basin, probably not much over 2,000 feet are represented. 



In Kentucky, while reaching a thickness of 1,000 to 1,250 feet in the 

 folded mouutaiuous region, only 150 feet of the Devonian are present in 

 the basin. 



In Tennessee some 1)00 feet are found in the mountains, but only 50 

 feet in the basin, and even this is sometimes cut out l:)y erosion, i^shley^' 

 states that of 35 oil liorizons recognized in Pennsylvania, 26 have no rep- 

 resentation in Tennessee, largely because of the thinning out of the De- 

 vonian, while 4 more occur only in the hills, which leaves only 5 strati- 

 graphic horizons in common. 



In Alabama the Devonian is reduced to a thickness of 25 feet where 

 present, and is often cut out entirely by unconformity. 



From the above it will be seen that 7 5 per cent or more of the northern 

 petroliferous horizons are absent south of central West Virginia. There 

 is, on the other hand, a considerable increase in the thickness of the Potts- 

 ville; but, unfortunately, so far as testing has shown, there has been 

 nothing to encourage the expectation of commercial oil. 



The stratigraph}^, considered by itself, tends to indicate that compara- 

 tively little oil will be found from southern West Virginia southward 

 across Kentucky, Tennessee, and Alabama. While small pools will un- 

 doubtedly be discovered from time to time, large developments, such as 

 might materially raise the production or prolong the life of the Appa- 

 lachian field, are not, in the light of our present knowledge, to be an- 

 ticipated. 



EVIDENCE OF STRUCTURE 



West of the strong outlying folds paralleling the Allegheny front at a dis- 

 tance of 25 miles or more, the general structure is favorable to oil through- 

 out the entire oil belt from southern New York to central Alabama. 



In Pennsylvania, low folds, structural terraces, and warped homoclines 

 are all present in good development over practically the whole area of the 

 basin west of the line mentioned. TJie same is true of northern West 

 Virginia. Toward the Kentucky line the folds become less conspicuous, 

 although by no means absent, the predominant structural feature being 

 the somewhat Avarped westward-dipping homocline. Within the State of 

 Kentucky the dip of the homocline first flattens, then changes to a west- 

 ward inclination, although still retaining structural warpings favorable 

 to oil. 



21 Geo. H. Ashley : Res. of Tenn., vol. ii, pp. 262-272. 



