3(58 GEOLOGY OF THE DENVER BASIN. 



field. At the time of examination, in the tall of L890, it was too slightly 

 developed to afford mure than a section of the scam worked. (PI. XX, 

 Fig. X.) The measures were then reported to rise rapidly to the south 



and west, and the coal to deteriorate. 'The 5-fool layer was the only one 

 worked. It lies at a depth of 70 feet below the collar of the shaft. 



Regarding the Northrup and other abandoned mines no data are. 

 attainable. 



'The coal of the Canlicld-Lrie area resembles in every detail that of 

 ili,' Mitchell basin. 



The sections of the seams worked in the Erie-Canfield district are 

 shown in Figs. K. L, and M, PI. XIX, and Fig. X, PI, XX. 



Till: AREA I VST OF GOAL GREEK. 

 General description. Idle WeStel'll slope of the high rfdg6 lletWCOll ('oal 



ami Dry creeks is underlain by strata that were at one time directly 

 continuous with those of the Coal Creek syncline. The measures out- 

 cropping are the upper ami lower Laramie and the highest layers of the 

 Fox Hills. The area is one of gentle flexures, with a balance of dip to 

 the easl <>r southeast and a strike varying between north and northeast. 

 < (ccasionally a curvature is sharp, but the displacement is always limited. 

 The chief faults are the Coal Creek, which limits the area on the west, and 

 the Baker, which passes just east of the Baker mine, with a trend X. 61° 

 ,".."i E. The cross-fault in the angle between the two is of little importance. 

 Other faults may have been developed from some of the sharper folds, but 

 they can not lie detected at the surface. 



The coal measures extend northeast, east, ami southeast an undeter- 

 mined distance beyond the map limits. With the exception of an outcrop 

 on the west side of the Baker fault, along it* southwestern half they lie at 

 a considerable depth beneath the surface. Along the Baker fault they rise 

 in outcrop between 1 \ and _ miles northeast of the Maker mine, followed 

 liv the basal sandstones of the Laramie in a gulch but a mile north of the 



mine, these li\ the Fox Hills in one only half or three-fourths of a mile 

 north. Between the last point and the mine the coal measures with the 

 lower beds of the upper Laramie have escaped erosion and occupy the 



