NORTHERN FLANKS OF THE UINTA RANGE. 321 



Northern Flanks. — The canon of the Upper Weber runs approxi- 

 mately with the strike of the upturned beds, forming the northern flank 

 of the Uinta upheaval. At the mouth of the canon is found a body of drab 

 limestones, forming its southerft wall, having a dip of about 25° to the 

 northwest. They extend for a distance of 1^ miles to the south of the 

 Weber River, along the foot-hills bordering Kamas Prairie, In these lime- 

 stones were found the following fossils: 



Produdus semireticulatus. 

 Spiriferina pulchra. 

 Martinia lineata. 



About 2 miles up the canon, the red sandstones of the Triassic are found 

 overlying conformably the upper shaly beds of , these limestones, and in the 

 north wall of the cation are seen outcrops of the compact drab limestones 

 of the Jurassic, which, to the westward, soon pass under the trachyte flows 

 which cover the spurs on the north of Kamas Prairie. On the summit of 

 the peak, 5 miles north of the mouth of the canon, were found beds of white 

 friable sandstone, dipping more gently northward, overlying conglomerate 

 beds, which represent the continuation of the Dakota and Colorado Creta- 

 ceous as exposed in Weber Valley below Peoria. The upper portion of the 

 canon, to the point where it bends to the southward, has apparently been 

 carved out of the softer beds of the Triassic; but, owing to its wide bottom 

 and the soft gravelly slopes of the ridge to the north, which is capped b}'" 

 Tertiary conglomerates, no good exposures were found. To the south of the 

 canon, the hills are mainly formed of the upturned Carboniferous limestones, 

 which are exposed in section in Berry Creek. The steep northern dips con- 

 tinue up this creek to near its head, exposing the Weber Quartzites lying con- 

 formably under the limestones, while at the very head of the canon the dip 

 suddenly changes to a slope of 5° to the southward, as is almost invariably 

 the case on the northern edge of the Uinta. In one of the basin-like heads 

 of this canon, the green and purple clay beds, which have been noticed in 

 other parts of the range enclosed within the quartzites, are shown in con- 

 siderable extent. They are remarkably soft and uncompacted, being almost 

 without structure-lines, although the quartzites in this region show much 



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