BEDROCK OF STAR PEAK RANGE 317 



flanks have suffered from no corrasion due to intermontane valley- 

 streams. 



Neighboring Areas 



application of previous investigations 



For the southern group of the Humboldt mountains the description, 

 discussion, and tests applied have been presented in considerable detail. 

 With these facts and conclusions in mind we may examine some of the 

 neighboring uplifts. If these present a general analogy to the range 

 studied, and if one or more of the criteria of faulting apply, we may be 

 satisfied as to their history and origin without as complete and detailed 

 a study as was given the first range. 



STAR PEAK RANGE 



The bedrock complex. — The Star Peak range has already been referred 

 to as the northern division of the Humboldt mountains, which is sepa- 

 rated from the southern division by a transverse valley. It is consider- 

 ably higher than the southern division, although not so long. 



The bedrock complex of this range is composed of practically the same 

 horizons as in the range already discussed. Indeed, paleontologic evi- 

 dence of the age of the various members is much more abundant. Ac- 

 cording to Professor J. P. Smith, the limestones of the Star Peak range 

 belong to two different horizons, the lower, in Star canyon, being Middle 

 Trias, the upper massive limestone being Upper Trias. The most diag- 

 nostic forms he finds in the Middle Trias are: Analcites whitneyi Gabb, 

 Beyrichites rotelliformis Meek, Ceratites nevadensis Mojsisovics, Ceratites 

 (Gymnotoceras) blakei Gabb, Sageceras gabbi Mojsisovics, Joannites gabbi 

 Meek, Daonella dubia Gabb. 



There are also many new species not yet described. Characteristic 

 Upper Triassic and Jurassic forms have already been given in speaking 

 of the bedrock complex of the Humboldt Lake range. Furthermore, 

 Doctor Smith has been unable to find any fossils below the Middle Trias 

 or above the Lower Jura (Lias) in either the Star Peak or the Humboldt 

 Lake range. 



It may be said that, allowing for a certain amount of variation, the 

 bedrock complex of the Star Peak range is very similar lithologically to 

 that of the Humboldt Lake range. It consists of Triassic and Jurassic 

 marine sediments associated with various igneous rocks. These sedi- 

 ments are folded, faulted, somewhat metamorphosed, and intruded, as 

 described for the other range. 



The granite and time of its intrusion. — No exposure of granite was found 

 in the Humboldt Lake mountains, but a considerable area is exposed 



