430 GEOLOGICAL EXCURSION TO THE ROCKY. MOUNTAINS. 



MANITOU. 

 By Whitman ClKttB. 



Manitou is a watering place and Bummer resort, celebrated for its 



springs of mineral water and the many objects of interest in its imme- 

 diate vicinity. It has five large hotels and many smaller ones. The 

 town lies in the valley of Fountain creek, in a little hay Indenting the 

 foothills of the Archean mountains. The sedimentary rocks occupying 

 this hay are of Silurian and Lower Carboniferous ages, and do not 

 appear elsewhere for many miles north or south. Although the details 



of the local geology have not been accurately worked out, the general 

 Structure is shown by the Hayden ma]). 74 To the north the strata 

 are seen resting on Archean gneiss, with a southerly dip of 10° to 38 

 and running well up on the mountain slopes, but only small patches 

 appear to the north of the stream which issues from the foothills at 

 Glen Eyrie, three miles from Manitou. The disappearance of the forma- 

 tions in this direction seems to be caused by erosion preceding the 

 Trias, for the shore line of the latter formation shows a transgression 

 from the Archean obliquely across the Silurian and Carboniferous. 



To the south of Fountain creek the Paleozoic, Triassic, Jurassic, 

 and Dakota Cretaceous beds are successively cut oil' by a fault line 

 with northwest southeast trend. This line crosses Ruxton creek west 

 of town near the Midland Railroad bridge. In the line of this fault 

 to the northwest is Manitou park, a long, isolated basin in the moun- 

 tains, occupied by the Paleozoic formations seen at Manitou, but with 

 a somewhat different development 



The best opportunity to see the Silurian beds and the contact with 

 the underlying Archean is in Williams canyon, a narrow, picturesque 

 gorge, whose mouth is close by the Clitf House. The canyon extends 

 almost due north for about two miles, its nearly vertical walls, 'M)0 to 

 500 feet in height, being mainly made up of Silurian limestone. 

 Ascending the canyon from Manitou one descends geologically, owing 

 to the southeasterly dip of the strata, and at about one mile from the 

 town the contact of the thin quartzite under the limestone with the 

 gneiss is very plainly seen. In the cliffs on the western side are 

 extensive caves in the most massive stratum of limestone. The "Cave 

 of the Winds'' is open to visitors. There are several other caves at 

 the same horizon in the vicinity of Manitou. 



By passing up Cte creek to Rainbow falls, one mile from the bath 

 house, another good view of the lower part of the Silurian section and 



