WEBER PEAK. 1(}1 



cross the Alpha fault, at least the limestones appear to have undergone no 

 displacement, West of the Alpha displacement the course of the east and 

 west fault after passing Weber Peak is lost, being buried beneath the accu- 

 mulations of igneous rocks. 



The thickness of the Lower Coal-measures may be best estimated 

 south of Fusilina Peak, where the upper members of the epoch are deter- 

 mined by the position of the Weber conglomerate, and, although there ex- 

 ists no positive evidence that the beds resting on the White Pine shale are 

 the equivalent of the lowest members found elsewhere, they probably do 

 not belong far above the base. It is estimated that the limestones measure 

 about 3,800 feet in thickness. 



Organic remains may be found scattered throughout the limestone, but 

 nowhere were any grouping of species obtained which were of special in- 

 terest or which could be regarded as the equivalent of the Spring Hill 

 fauna. At the head of Newark Canyon, which starts in near the base of 

 the limestone immediately resting on the White Pine shale, were found 

 Producing longispinwSj P. semireticulatus, and Spirifera camerata, while south of 

 Fusilina Peak, at the top of the horizon, the same species occur associate! 1 

 with Fusilina cylindrical and other Coal-measure forms. On the map will be 

 found a number of localities designated where fossils were procured but 

 they indicate only a few of the horizons where they are known to exist. 



Weber Peak and Pinto Springs Region. Under this heading may be designated 

 the area of the Weber conglomerates lying between the two great bodies 

 of Carboniferous limestone. From Weber Peak southward they overlie 

 conformably the Lower Coal-measures, although not extending southward 

 out into the open valley quite as far as the limestone, being buried beneath 

 either basaltic flows or the alluvial deposits of Pinto Creek. Along the 

 line of contact the Weber conglomerates form a well defined series of ridges 

 parallel with the Alpha and Fusilina ridges, the two formations standing out 

 sharply contrasted by their surface forms, atmospheric agencies acting quite 

 differently on the fine crystalline limestones and the coarse conglomerates. 

 In like manner erosion acting upon the more easily disintegrated conglom- 

 erates has worn out a number of narrow drainage channels along the con- 

 tact which serve still more sharply to define tin- boundaries. The conglom- 

 MON xx 11 



