432 F. B. WEEKS STEATIGEAPHY OP THE UNITA RANGE 



stream" ceased its movement, preceded by little if any transportation 

 by ice. 



These accumulations of rock do not have the smooth, regular lines of 

 the ordinary talus slope nor the familiar form of terminal moraines. 

 They more closely resemble a fall of rock fragments from a cliff, but in 

 these instances the movement must have been as a mass and not as de- 

 tached rock fragments. 



Geology 

 general sections of wasatch, uinta, and grand canyon regions 

 The tables following are comparative generalized Paleozoic sections by 

 King, Walcott, and the writer. 



GEOLOGIC MAP 



The base of the geologic map, figure 2, is that of the 40th Parallel 

 map. The writer is responsible for the geology except for the region east 

 of Brush creek and Green river, on the south side of the range. This 

 was copied from the 40th Parallel map. 



GENERAL FEATURES 



The basement rocks upon which the earliest sediments were laid down 

 are not exposed, and no lava flows or intrusives are involved in the uplift. 

 The oldest sedimentary rocks form the broad top and upper part of the 

 anticlinal slopes and each succeeding stratum passes beneath a later one 

 in regular order of deposition. 



The section extends from the pre-Cambrian to the Cretaceous, inclusive. 

 It consists of sandstones, limestones, and shales, essentially conformable 

 in structure, although certain members are absent by non-deposition and 

 possibly by erosion. 



Subsequent to the iiplift a considerable part of the fold was buried be- 

 neath Tertiary sediments, which have in great measure been removed by 

 erosion during later Tertiary or Quaternary time. Eemnants of such 

 deposits have been left on the higher parts of the flanks of the range, and 

 in some areas completely cover the lower slopes. Quaternary deposits of 

 glacial origin lie on the older sediments of the interior, and fluviatile 

 gravels and sands occur in terraces overlying the younger sedimentary 

 strata. The stratigraphy is in part 'similar to the succession exhibited in 

 the central Wasatch region and the canyon of the Colorado, but it pre- 

 sents also many distinctive local features. 



The Duchesne river has cut a deep canyon in the strata which form this 

 range. In figure 3 is given the section as exposed on the west side of the 



