578 W. T. LEE STRATIGRAPHY OF COAL FIELDS OF NEW MEXICO 



Apparently Cope either did not find the "Laramie" of this region at this 

 time or did not separate it from the overlying Tertiary rocks. 



Again, in 1875, Loew (41) describes the "Cretaceous" coal beds near 

 Nacimiento, and also those farther south on the Rio Puerco near San 

 Ygnacio (42), as well as those in the Cerrillos and Tijeras coal fields. 

 Analyses are given of the bituminous coal from Xacimiento and of the 

 anthracite from Placer Mountain in the Cerrillos field. About the same 

 time Stevenson presented a paper apparently not published until the fol- 

 lowing year, in which he mentions the Galisteo formation, and Cope (39) 

 criticized the paper, stating that the Galisteo sandstone is Triassic in age 

 (probably misled by the color of the rocks). The same error seems to 

 have been made ]\v others, for several contemporaneous writers refer to 

 great numbers of petrified trees in the Trias of the Cerrillos region, 

 whereas no rocks now admitted to be of Triassic age occur in this region, 

 and all of the petrified wood known to the present writer is in the Galis- 

 teo sandstone. It does not appear from the literature that Cope actually 

 visited the Cerrillos coal field at this time, as his route was from Santa 

 Fe to the Sandia Mountains west of the field, but his descriptions are 

 such as to indicate that he regarded the coal beds which he evidently 

 knew lay east of his route as belonging in the Cretaceous, at least as 

 high as number 4 (Pierre), inasmuch as his diagram (36) shows the 

 occurrence of number 4 stratigraphically below the horizon where the 

 coal is now known to occur. However, Stevenson (53) states that Cope 

 referred the coal to Cretaceous number 3. In this same paper (36) Cope 

 describes, in considerable detail, the coal measures west of Nacimiento 

 Mountains. He referred the coal beds, which later writers have called 

 Mesaverde, to Cretaceous number 3 (Niobrara), and found above them 

 fossils which he regarded as indicative of Cretaceous number 4 (Pierre), 

 which apparently is the Lewis shale, later described as occurring above 

 the Mesaverde coal measures in this region. In another paper Cope (38) 

 -gives a graphic section of both Cretaceous and Tertiary formations, in 

 which he indicates a covered area between his Cretaceous number 4 and 

 the overlying Puerco formation. 



In 1874 Cope (23) announced that he had found dinosaur bones 

 wliich, in his opinion, proved that Hayden's "lignitic group" was Cre- 

 taceous in age, and Hayden (28) replied that he admitted the Cretaceous 

 age of some of the coal beds of Utah, Arizona, and western Xew Mexico ; 

 also, Newberry asserted that he had proved the coal beds of New Mexico 

 to be Cretaceous by the discovery of marine fossils above them (28 and 

 32), and that all of the plant-bearing coal beds in New Mexico are of 



