1(52 GEOLOGY OF TUE EUKEK.V DISTRICT. 



erates stx'etcli out toward the west until cut ofl" by the broad basaltic table- 

 land of the Strahlenberg, which, concealing everything over a wide area, 

 leaves to conjecture the probable structural relations of the Carboniferous 

 rocks of the Diamond Range t(i tlie immense block of Devonian limestone 

 of the County Peak iiplift. East of Strahlenberg, the highest point on the 

 eastern rim of the basaltic field, the conglomei-ates present a broad, high 

 ridge, with a strike of N. 30° W. and an easterly dip of 75°. It is against 

 this ridge that the basalts have been piled up, the ridge acting as a barrier 

 to their further progress in that direction. Between the basalt and tlie 

 Lower Coal-measures of Alpha Ridge the conglomerates are plicated into 

 a broad syncline followed by a sharp anticline, the axes of both folds being 

 traceable the entire length of the conglomerate area. The conglomerate 

 ridge lying next to the Lower Coal-measures forms the east side of the 

 syncline, the beds coming up again on the opposite side of the fold in a 

 ridge nearly parallel with the first one. The anticlinal fold presents a much 

 sharper axis, the beds on both sides of the arch dipping at angles varying 

 from 55° to 65°. 



One of the most fortunate occuiTences in working out the structiu-al 

 geology of the region is the belt of light gray Upper Coal-measure lime- 

 stone lying between the westerly dipping beds of the anticlinal fold and 

 the basalts. It furnishes within the district e-vddence of the position of 

 the Weber conglomerate between the two great belts of Coal-measure lime- 

 stone and although ample proof could be found elsewhere, it makes the 

 chain of evidence com])lete for all the divisions of the Paleozoic series 

 of rocks in the Great Basin. It is a narrow strip of limestone, in places 

 onl)' a few hundred feet in width and about one mile in length, being cut 

 ofi" both at the north and south by igneous rocks. It strikes nearly north 

 and south and dips between 55° and 60° to the west, coinciding with the 

 inclination of the underlying conglomerates on the west side of the anti- 

 clinal fold. In a yellowish gray bed occurs a characteristic fauna of the 

 Upper Coal-measures ; a list of the species procured here will be found 

 elsewhere. The continuity of this body of Upjier Coal-measure limestone 

 with the larger body north of Newark Canyon is broken not only by 

 igneous flows, but the connection is completely severed by a line of f;udt- 



