Maryland Geological Survey 83 



The Lower Devonian rocks of western Maryland lie in two areas situated 

 in Allegany and Washington counties respectively. The area in Allegany 

 County may be called the Cumberland area and that in Washington 

 County the Hancock area. Of these areas that of Cumberland is by far 

 the larger and has long been famous as a collecting ground for fossils, 

 especially those of Oriskany age. 



In the Cumberland area the Lower Devonian formations lie around the 

 Wills Mountain, Evitts Mountain, and Tusseys Mountain anticlines. The 

 Potomac Eiver and Wills Creek cut through the Wills Mountain anticline 

 at Cumberland and render the sections there among the best in this region. 

 About the Evitts Mountain anticline the exposures are less perfect. Flint- 

 stone Creek, in cutting through the Tusseys Mountain anticline, also 

 affords some exposures of importance. Besides the larger outcrops in the 

 Cumberland area there are three smaller ones. One of these, Avhich ex- 

 poses the Oriskany sandstone alone, begins opposite the South Branch of 

 the Potomac Eiver and extends in a narrow tongue up the Town Creek 

 Valley. The others are along the Potomac at Fort Hill and Monster Rock 

 in the southwestern part of the county near Keyser, West Virginia, and 

 lie on the northern extension of the New Creek Mountain anticline. 



The Lower Devonian is also exposed in three areas near Hancock. The 

 largest of these is west of Hancock and extends in two narrow strips 

 across the State about the northern end of the Cacapon Mountain anti- 

 cline. The exposures are good wliere this anticline is cut by the Potomac, 

 the finest being at Tonoloway Station, in the cut of the Western Mary- 

 land Eailroad opposite Great Cacapon, West Virginia. A second exposure 

 is about the southern end of the Cove or Tuscarora Mountain anticline, 

 which is cut by Licking Creek along the Mason and Dixon line, some of 

 the best sections of the Lower Devonian rocks in Washington County being 

 found here. A third area is along the western slopes of Hearthstone and 

 North mountains where the best exposures are again due to the ciitting 

 of the Potomac Eiver at Cherry Eun. The localities best adapted for 

 study are described in the discussion of the local sections. 



