TRIASSIC PORTION OF SHINARUMP GROUP iii 



5 

 4 

 Moencopie / 3 

 beds 



Dark chocolate-brown, argillaceous shales; saliferous 

 Argillaceous sandstones, soft, dark brown 

 Argillaceous shales, dark brown 

 Calcareous shales, white 

 Aigillaceous shales, saliferous . 



Total 



Limestone or Sandstone of Aubrey (Pennsylvanian) 



In a later publication Ward revises the nomenclature of this 

 section, speaking of the Moencopie, Shinarump, and Painted Desert 

 formations, and under the Shinarump distinguishing the Leroux and 

 Lithodendron members, the latter corresponding to the Shinarump 

 conglomerate of his section (27, pp. 13-46). The term "Lithoden- 

 dron member" refers to the fossil tree trunks, but is not distinctive, 

 since these remains are also prominent in the Leroux member. 



The discovery of a vertebrate fauna associated with fossil wood 

 in a definite part of this section is certainly a most important contri- 

 bution, but the systematic treatment by Ward is rather confusing as 

 he does not attempt to harmonize his results with those of Powell, 

 Dutton, Walcott, and others, which are, for the most part, not even 

 referred to. 



The Painted Desert formation, upon which, according to Ward, 

 "the Cretaceous lignites and limestones lie unconf ormably " (26, p. 

 412) is clearly the equivalent of the Vermilion Cliff and White Cliff 

 sandstones, although he makes no reference to earlier opinions or 

 statements concerning the extension of these formations into the 

 area where his section was made. 



The Moencopie formation, on the other hand, corresponds in 

 position and general character to the Permian beds found by Walcott 

 in the Kanab section. Ward, however, found no fossiliferous lime- 

 stones and makes no allusion to the work of Walcott; but if the 

 Moencopie beds are Triassic they clearly belong in the Shinarump 

 Group of Powell. In any case. Ward's use of Shinarump in a third 

 sense, as a formation name for 1,600 feet of strata, seems unwarranted. 



The correlation of eight hundred feet of sediments of variable 

 character, grading into marls in some places, with the Shinarump 

 conglomerate, is a procedure requiring clear justification by facts of 



