338 GEOLOGY OP THE DENVER BASIN. 



east of the Ralston dike. The dip is vertical, or nearly so, for the entire 

 distance given. The old Murphy shaft on the north side of the creek, 

 said to be sunk on the eastern of the two workable scams, is about 125 

 feet east of the base of the Laramie, which would place the seams in the 

 same general horizon as the others along the foothills; that is, in the zone 

 between sandstones B and C. From surface relations between points along 

 a gradually shallowing dip, from the thickness of the formation, and from 

 the recognized horizons, it is estimated that the coal measures would be 

 found under the region of slightly dipping strata, between a quarter and 

 half a mile to the east of the old mines, at a depth of 1,200 feet beneath 

 the creek level, the fold by which the beds are upturned being sharp and 

 pronounced. 



The extent of the productive measures of this locality can not be 

 greater than half a mile to the south of Ralston Creek, while to the north it 

 may extend with some interruptions as far as Leyden Gulch, a distance of 

 about 2 miles. In depth the beds probably extend far below economically 

 workable limits. 



Fig. 12. — Section showing coal measures of lower Laramie at Coal Creek. 1. Sandstone, 

 white, heavy-bedded. 2. A succession of sandstones and shales with occasional ironstones. 

 3. Coal; brown shale just above and below. 4. Sandstones, white, heavy-bedded. 5. Coal. 

 This seam has been slightly worked for local trade. 7. Sandstone B. 



The coal of the Ralston Creek mines, of which the principal one was 

 the Murphy, is reported hard and lustrous. This mine has produced as 

 high as 50 or HO tons per day, and a, possible total of 25,000 tons. 



RALSTON - CREEK TO MARSHALL. 



The Leyden mine. — This is located in Leyden Gulch. It was originally a 

 small producer, but has long been abandoned. From reports it is believed 

 that the beds have changed in their character, forming, perhaps, the northern 

 limit of the Ralston area. 



From Leyden Gulch to Coal Creek the basal sandstones of the 

 Laramie outcrop in low combs at a number of places. At Coal Creek 

 the measures afford the above section (fig. 12). 



