JIAEV1.NF..J GEOLOGY ROCKS EAST OF FRONT RANGE LIGNITIC. 121 



outcrops on the bank, and there appears as of a very poor qualitj-. 

 Fossil-leaves are abundant. 



It was near here that the first discoveries of coal were made in Colo- 

 rado, and the stream at this point is often known as Coal Creek, though 

 called Sand Creek farther down. The latter name should be retained, 

 to prevent confusion between this and the better known Coal Creek on 

 the west side of the Platte. 



About four miles to the north, near Box Elder on the Kansas Pacific 

 road, in range 65 west, township 3 south, section 28, (?) and probably 

 in the same horizoij as the last, are two shafts which reach coal, and on 

 which work has been done now and then for some years. It is probably 

 in one of these three shafts that the following section was made by Mr. 

 E. B. Mally, (quoted by Lesquereux in Hayden's report for 1872, p. 327,) 

 and which serves to give an idea of the strata near here : 



Section of strata in shaft fourteen miles east of Denver. — E. B. Mally. 



No. 



Nature of strata. 



Thickness. 



Top. 



Slaty clay 



Siind 



Yellow clay 



Light-blue soapstoue 



Brown soai^stone 



Soapstoue and clay 



Drab soapstoue 



Dark- brown soapstoue 



Black slate, with veins of coal 



Coal, wet and smutty 



Coal, better 



Black-clay parting _ 



Coal 



Soapstoue, blue, brown, and black. .. . 



Hard saud-rock 



Spotted sand-rock 



Very hard saud-rock 



Soft sandy clay 



Bottom 



■ Total 



Feet, in. 



16 







18 







5 







6 







2 







13 







14 







2 







5 



6 



4 







3 









4 



1 







24 



7 



1 



4 



12 







5 







9 



6 



142 



The work was abandoned on account of the poor quality of the coal. 

 Professor Lesquereux thinks that the section indicates the horizon of 

 the bed as being at the top of the great liguitic or fucoidal sandstone 

 under the series of beds of clay and soapstone, as at the Eaton Mount- 

 ains. 



PlattevillCj range GG west, township 3 north, sections 17, 18, 19, 20; 

 coal in small veins, now owned by the Saint Vrain Coal Company. 



McKissack, range 67 west, township 2 north, sections 18, 19 ; coal 

 in bed or beds some 10 feet thick, now coking, crumbling, and with but 

 little suli)hur, as usual. 



Erie mine, range 68 west, township 1 north, sections 7 and 8, called 

 also the Briggs mine. This opening, which is one of the larger ones, 

 is on.the west side of a hill facing Coal Creek, the opening being down 

 the gentle slope of the bed east-northeast into the hill. 



In 1870 the main adit had been driven 500 feet, with galleries on 



