CONEMAUGH FORMATION IN WEST VIRGINIA 203 



Feet. Inches 



13. Shales and concealed 55 



14. Ames limestone 1 6 



15. Variegated shale 85 6 



16. Cambridge ( ?) limestone 1 



17. Shales 14 



18. Buffalo sandstone 3 6 



19. Shale and shaly sandstone 30 



20. Mahoning sandstone 100 



21. Shales 40 



to the Upper Freeport — in all, 561 feet. The Mahoning deposit con- 

 tinues upward, so as to pass the place of the Brush Creek coal and lime- 

 stone. Nine miles south from Morgantown the Conemaugh is said to be 

 587 feet thick, the increased thickness being above the Ames limestone. 

 The Brush Creek coal bed is at 99 feet above the Upper Freeport and 

 underlies directly the massive Buffalo sandstone, which is 53 feet thick. 

 The Barton and Anderson coal beds and the Cowrun sandstone do not 

 appear in these sections. 



Westward from the Monongahela one is dependent wholly upon the 

 records of oil borings. Possibly because these are very numerous, the 

 variability of the sandstones and red beds is much more marked in them 

 than in the less numerous measurements of exposures. It may be that 

 some of the variations are due to the inaccuracy of measurements by the 

 drillers. In any event, it is necessary at the outset to state that while it 

 is not altogether difficult to recognize any given sandstone horizon, still 

 the correlation is never wholly exact, since, using the Pittsburg coal bed 

 as the fixed horizon, one finds the top or bottom of each sandstone shift- 

 ing in such fashion that the determination can not be in close detail. 

 The limestones, so important in tracing the section by exposures, are 

 very thin and do not appear in the records. The coal beds quickly be- 

 come indefinite and disappear, while the red beds are distributed with 

 such irregularity that they seem to mark localities of lagoons. 



In Monongalia and Marion counties, west from the Monongahela river, 

 the interval from Pittsburg to Upper Freeport varies from 560 to 578 

 feet. In the former county at 10 miles northwest from Morgantown it 

 is 570 and in the latter at 12 miles southwest it is 578 feet. The Mor- 

 gantown sandstone is well defined in many records and varies in thick- 

 ness from 50 to 120 feet, its top being at 140 to 160 feet below the Pitts- 

 burg; yet in not a few records it is represented only by shale. The 

 Cowrun sandstone, overlying the Cambridge limestone, does not appear 

 in the Monongalia wells except near the western border, but it is recorded" 

 occasionally in the Marion wells at about 350 feet below the Pittsburg. 



