188 RESOURCES OF TENNESSEE. 



for some 40 or 50 feet, when more massive limestone appears and con- 

 tinues down for more than 600 feet. At the top, this massive limestone 

 may show a few feet of brown oil-bearing dolomite, as in the West No. 1 

 and Toomey No. 2 wells, and some 10 to 20 feet below it there are a few 

 feet of gray oolitic limestone. Lower in the section some hard cherty 

 material is found and some thin shales may appear, but from the records 

 no distinct separation of the material down to the Chattanooga black shale 

 seemed possible, though it is probable that the lower part of what is here 

 grouped together as the Newman limestone is the equivalent of the Wav- 

 erly. Parts of this limestone are more or less magnesian or dolomitic, 

 while other parts are very dense and fine-textured. The horizon of the 

 Beaver "sand" occurs in the lower part of this long limestone interval, 

 but was not found to be oil-bearing in the Toomey No. 1 well. The total 

 thickness of the Newman, or Newman- Waverly, in that well was 725 feet, 

 while in the Winfield well it is 675 feet, in the Rugby well 695, and in the 

 Rugby Road one 713 feet. It is the oldest of the Mississippian or sub- 

 Carboniferous formations. 



Where the Newman limestone rises to daylight in Overton and Fentress 

 counties some 35 to 50 miles west of this region, it contains a sandstone 

 lentil about 150 feet from the top, that was at first thought would prove 

 to be the oil-bearing member in this Oneida region, but the chemical analy- 

 sis of the oil-bearing rock given on a succeeding page makes it certain 

 that it is either a pure or a dolomitic limestone. The horizon of the oil 

 "sand" is, however, not far from the horizon of the sandstone lentil. 



Chattanooga black shale. This is a homogeneous fine-grained black 

 shale, of Devonian age, that is reached in only the deeper wells of the 

 region. It is so different in color and character from the materials above 

 or below that it is very easily recognized and serves as an excellent horizon 

 marker. It seems to vary from 40 to 65 feet in thickness in the few well 

 records available. 



Silurian and Ordovician rocks. Beneath the Devonian black shale 

 there is a long succession of blue and gray limestones and shales as re- 

 corded in the records of the Toomey No. 1 and the Rugby Road and 

 Rugby wells. There is very little in these records, however, upon which 

 to base an opinion as to what part may be Silurian and what Ordovician 

 in age. The soft shale just beneath the Chattanooga black shale may be- 

 long to the Osgood formation of the Silurian and the hard blue limestone 

 below it may either represent the Clinton and hence be also of Silurian 

 age, or may belong to the Hudson River or Cincinnatian group of Ordo- 

 vician age. Somewhat farther east at Elk Valley and along the Cumber- 

 land front the Clinton contains a red fossil iron ore that should be care- 

 fully looked for in wells that penetrate any distance below the Devonian 



