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GUIDEBOOK OF THE WESTERN UNITED STATES. 



tanks may be seen on both sides of the railroad. From Florence a 

 branch railroad turns to the south (left) and runs through the heart 

 of the oil field and to Coal Creek, where there are coal mines that 

 ship their product both east and west over the Denver & Rio Grande 

 Western Railroad. 



During the early days of mining in the Cripple Creek gold dis- 

 trict the entire output of ore was refined at Florence. Nine enormous 

 reduction mills were operated in this vicinity until the Golden Cycle 

 mill was built in Colorado City, when trouble with labor caused the 

 ore to be sent to Colorado City and Denver. The mills continued to 

 operate for a number of years but were finally closed. One of these — 

 a million dollar plant — is still standing on the north side of Arkansas 

 River about half a mile north of Florence. 



About three-quarters of a mile west of the station the railroad 

 crosses Oak Creek, and from this crossing the traveler may see off 

 to the southwest (left) the distant slopes of the Wet Mountains and 

 nearer, but still 3 or 4 miles distant, the white-banded hills that 

 mark the outer rim of the Canon City coal field,^^ a basin of Laramie 



for about 3 miles. The quantity of oil 

 produced in this field in 1918 was 

 134,895 barrels, and the total quantity 

 produced since the field was developed 

 has been move than 10,500,000 barrels. 

 The oil has a paraffin base and is a 

 light oil, yielding a large percentage 

 of gasoline. 



The Florence oil field is apparently 

 different from any other field in this 

 country, as the oil is found part way 

 down on the east side of a large struc- 

 tural basin or syncUne. The oil does 

 not come from sands, as the drillers 

 call any coarse-grained rock that car- 

 ries oil, but from the fine Pierre shale. 

 It does not, however, appear to be in 

 the pores of the shale but in cracks 

 and crevices. In drilling wells in this 

 field the tools often drop several feet, 

 and sometimes the bailer — a long tube 

 by which the oil or water is bailed out 

 of the well — has been lost in one of 

 these crevices. Altogether, this field 

 is an anomaly and is not well under- 

 stood by geologists. 



Another curious fact is that the oil 

 which flows from the spring noted 

 above, as well as from others that have 



been discovered more recently, does 

 not come from the outcrop of this 

 shale but from the Morrison forma- 

 tion, which underlies the shale and is 

 beneath the Dakota sandstone. 



The Florence oil field is the largest 

 field of its kind in Colorado and has 

 been a steady producer for a long 

 time. Tw^o refineries are in operation, 

 and the oil is piped to the railroad 

 from different parts of the field as well 

 as shipped in from other fields in the 

 State for refining. 



*^The Canon City coal field is a 

 small structural basin, or syncline, in 

 the Laramie formation south of the 

 Denver & Rio Grande Western Rail- 

 road and extends from a point a short 

 distance west of Florence to the foot 

 of the Wet Mountains. The coal-bear- 

 ing beds on the east side of this basin 

 dip westward at angles of 2° to 5° 

 except at the northern margin, where 

 the dip ranges from 5° to 15°. Their 

 outcrop here, which is broader than it 

 is on the west side, is 2 to 4 miles 

 wide and about 12 miles long. It con- 

 tains all the large mines of the field, 

 eight in number, that ship their prod- 



