98 EXPLORING EXPEDITION FROM SANTA FF, 



Section of Carboniferous rocks in Labyrinth Canon. 



Feet. 



1. Blue slatv argillaceous limestone, with nodules of chert, and containing cri- 



noidal columns in great numbers, Athyris subtiMta, BeUerophon, Productus } dbc. 20 



2. Massive blue limestone, portions of which are quite sandy, generally variable 



in color and composition 50 



3. Slaty blue argillaceous limestone, somewhat chert)', crowded with fossils, among 



which are Athyris subtUita, Spirifer camerattcs, Productus semireticulatus, V. 

 scabriculuS) P. Rogersi, P. punctatus, P. nodosus, Orthisina umbraculum, Mya- 

 lina ampla, Pleurotontaria excelsa — a large and fine new species — AUorisma 

 subcuneata, &c 40 



4. Red shale, no fossils .'. 6" 



5. Bluish-white, red or mottled sandy limestone, no fossils 35 



(!. Red calcareous shale, no fossils 7 



7. Red or bluish- white, mottled sandy limestone, massive, no fossils 25 



8. Coarse blood-red sandstone, in some localities becoming red shah 1 , no fossils. . 22 

 !). I lard blue cherty limestone, with a few fossils of the same species found in No. 3 - 3G 



The last number of the series forms the fall or precipice which stopped our prog- 

 ress down the canon. The remainder of the section was inaccessible to ns; as seen 

 from above it seemed to consist of alternations of strata, similar to those already 

 enumerated. Jf we may judge of the thickness of the Carboniferous formation in this 

 vicinity by what it is lower down on the Colorado, we cannot suppose that the base of 

 the series is reached in the canon of Grand River. 



On comparing this exposure of the Carboniferous strata with that at Santa lu', 

 described in Chapter II of this report, and those of the banks of the Colorado below 

 the mouth of the Little Colorado, noticed in my report to Lieutenant Ives, Chapter VI, 

 pp. 60 and 62, it will be seen that the fossils are generally identical; that, while two 

 or three new species were added in each locality to the Carboniferous fauna of the 

 Mississippi Valley, most of them are the same with the most common and characteristic 

 fossils of our Coal-Measures in Illinois, Ohio, and Pennsylvania. 



In lithological characters there is a general correspondence between all the locali- 

 ties in New Mexico where the Carboniferous rocks are fully exposed, but at Santa Fe 

 there is a greater proportion of coarse material, sandstones and conglomerates, than at 

 /- the more western localities. At Santa Fe, too, we find land-plants, characteristic Coal- 

 Measure forms, and even a thin bed of coal; all of which indicate the immediate prox- 

 imity of dry land. 



Too little was learned of the lower part of the series on Grand River to enable 

 me to institute a fair comparison between the Carboniferous rocks at this locality and 

 those on Cataract Creek, 150 miles below. In the upper part of the formation we find, 

 however, here as there, cherty limestones with similar fossils, but the great beds of 

 gypsum of Cataract Creek are certainly wanting here. 



Combining the sections exposed at different points along our route in our descent, 

 step by step, from the summit of the Mesa Verde to the canon of Grand River, we 

 have tin? following resume of the strata and formations passed through : 



