CAEBON BASIN. 145 



up on the slopes, by the erosion of the softer clay-beds, protected by the 

 outer overlying sandstones. Along the east base of the ridge, the coarse 

 sandstones may be traced northward to the railroad-cut. Here, one mile 

 westward from town, a thin bed of coal is seen in a hard sandstone, which 

 carries a large amount of half-carbonized bits of wood, and is overlaid by 

 beds of arenaceous clays. A short distance farther north, ,on the west side 

 of a low ridge, with all the beds still dipping eastward, occur similar clay 

 and iron strata, as seen high up on Simpson Peak, associated with fine 

 calcareous sandstones. The beds of Simpson Ridge, in passing eastward, 

 shallow in dip, and may be traced passing conformably under the level 

 coal-bearing strata of the valley. Leaving, for the present, the detailed 

 description of the beds underlying Carbon, we find the strata for nearly 3 

 miles east of the town lying horizontally, and then gradually assuming 

 a westerly dip, forming the opposite side of a broad synclinal fold from the 

 Simpson Ridge beds. About 4 miles east of Carbon, near the first snow- 

 shed, rusty, yellow sandstones occur, dipping west at 25°, and carrying a 

 thin stratum of impure coal. A short distance farther eastward are found 

 very similar yellowish sandstones, with concretionary fragments of iron, 

 black clays, and friable sands, with intercalated thin seams of iron, still 

 preserving the same dip. South of Carbon, the beds incline gently north- 

 ward, and would appear to be perfectly conformable with the basin strata. 

 How far they extend southward was not carefully determined, but coal 

 outcrops in very similar beds are said to occur 4 or 5 miles south of the 

 railroad. Returning to the railroad, which crosses the synclinal basin near 

 its centre, the strata appear approximately horizontal, although, imme- 

 diately underlying Carbon, they are somewhat disturbed by local faulting, 

 bringing the beds which carry the main coal seam to the surface a short 

 distance west of the town. 



In company with the superintendent of the mines, the following sec- 

 tion was made of the beds underlying Carbon : 



Feet. 



1. Gravel and sand 6 



2. Brownish-gray sandstone 6 



3. Shales 4 



4. Sandstone , 4 



5. Shales 4 



10 D G 



