THE BASIN PROVINCE 129 



quartzite 430 feet farther down. In Weber Canyon this great formation is most 

 characteristically exposed as a massive, dense, homogeneous quartzite. The 

 insignificant exceptions are a curiously pitted and marked stratum of quartzite 

 just below the top and a few thin limestones in the basal portions. * * * 



"The passage from this great quartzite into the overlying formation has 

 been a subject of considerable study without definite results. One geologist 

 reported that a marked uniformity [unconformity?] existed between this quartzite 

 and the overlying limestone. During the present survey, however, excellent 

 exposures showed apparently complete conformity. The lithological character 

 of the sediments also indicated that a full record is here found of a normal gradual 

 transition. Exposures in Woodside Canyon show a succession of calcareous 

 sandstones, normal sandstones, and arenaceous quartzites immediately above 

 characteristic massive Weber quartzite — apparently a normal transition. In 

 Big Cottonwood Canyon, a few miles west of this area, the quartzite gives way 

 upward to a sequence of sandy beds. In Weber Canyon the precise contact 

 was not sufficiently exposed to demonstrate conformability, but the evidence 

 obtainable pointed to that condition." 



Schultz,' in 191 8, gave the following account of the Weber quartzite 

 in the Uinta Mountains: 



"Weber Quartzite (Pennsylvanian). 



"Overlying the massive Pennsylvanian limestones, which may be considered 

 as at least in part equivalent to the Morgan formation of the Wasatch Range, 

 is a thick massive gray to white quartzite or sandstone that has been correlated 

 with the Weber quartzite of the Wasatch Range. With this quartzite are asso- 

 ciated small quantities of chert and limestone. The absence of impurities and 

 cementing material is conspicuous. On fresh fracture the quartzite is pure 

 white to light brownish gray and it usually weathers to a light shade, although in 

 some localities it has a decided brownish color. The quartzite or sandstone is 

 fine, even grained, and dense. The exceedingly brittle nature of the rock causes 

 it to break into sharp, irregular fragments that form conspicuous talus slopes. 

 In some localities the sandstone has been so completely metamorphosed into 

 quartzite that the form of the original constituent grains is not readily discernible 

 by the naked eye. In many other places along both sides of the range, however, 

 the Weber quartzite is nothing more than a rather soft sandstone in which the 

 original grains are poorly cemented and readily detected and which on weathering 

 produces a fine-grained sand remarkably free from impurities. Good exposures 

 of this formation may be seen along both sides of the Uinta Range west of Green 

 River wherever the beds have not been obscured by the overlying Tertiary 

 deposits or by the Bishop conglomerate, of late Tertiary or early Quaternary age. 

 The distribution of these beds is shown on the accompanying map [PI. V, in the 

 original publication]. East of the area examined and east of Green River the 

 Weber quartzite beds are exposed by erosion at many places along the south 

 flank of the mountains and along the crest of the Midland anticline at the south 

 side of Blue Mountain, in Colorado, where it forms the center of the oval basin 

 south of Midland Ridge. 



' Schultz, A. R., A Geologic Reconnaissance of the Uintah Mountains, Northern Utah, with 

 Especial Reference to Phosphate, U. S. Geological Survey, Bulletin 690-C, p. 45, 1918. 

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