36 EXPLORING EXPEDITION FROM SANTA Ffi 



CHAPTER II. 



GEOLOGY OF THE VICINITY OF SANTA FE. 



GENERAL GEOLOGICAL FEATURES SANTA FE MOUNTAINS GRANITE ITS CHARACTER AND 

 CONTAINED MINERALS RELATIONS OF THE SANTA FE MOUNTAINS PLACER MOUNTAINS 

 CRETACEOUS AND TRIASSIC ROCKS CRETACEOUS LIGNITE CONVERTED INTO ANTHRACITE 

 BY AN OUTKUUST OF TRAP GoLD OF THE PLACER MOUNTAINS COPPER IRON TlIE 

 CERRILLOS GOLD SILVER LEAD COPPER IRON TURQUOISE ANCIENT CHALCIIUITL 

 MINES THE SANDIA MOUNTAIN THE VALLES STRATIFIED ROCKS CARBONIFEROUS 

 FORMATION SANTA FE SECTION SECTION AT PECOS VILLAGE PERMO-CARBONIFEROUS 

 BEDS GYPSUM FORMATION SECTION AT SAN JOSE FOSSIL PLANTS CRETACEOUS FORMA- 

 TION SUBDIVISION OF THE SYSTEM YELLOW SANDSTONES OF CANON BLANCO CRETA- 

 CEOUS SECTIONS AT GALLISTEO AND POPE'S WELL TERTIARY BEDS OF FRESH- WATER 

 ORIGIN. 



The region about Santa Fe has occupied the attention of several geologists who 

 have visited New Mexico, among whom Messrs. Wislizenus, Marcou, and Blake have 

 given full reports of their observations upon it. I also was able to devote a short time 

 to its study while connected with the party of Lieutenant Ives in 1858, a resume of 

 the observations then made being given in my report to that officer. It might, there- 

 fore, be supposed -that this subject was by this time freed from all obscurity, and, per- 

 haps, exhausted of all interest. This is, however, far from being true, as may be shown 

 in few words. The geological structure of that region is complicated by several distinct 

 lines of upheaval, which have been classed together in the so-called Rocky Mountain 

 system; and yet the relations of these groups and chains of mountains are far from 

 being fully understood, or at least demonstrated. They have been regarded, perhaps 

 justly, as of the same age, but, as will be seen, when we come to speak of them more 

 in detail, evidence of complete synchronism is yet wanting, while there are some facts 

 which seem to point to a contrary conclusion. 



Aside from the obscurity which hangs over the erupted rocks, an obscurity that 

 cannot be dissipated without much careful study in the field as well as in the labora- 

 tory, the splendid exposures of the three great groups of sedimentary strata, the Car- 

 boniferous, the Triassic, and the Cretaceous to say nothing of the Tertiary beds 

 largely developed, but without fossils: deserve and demand for their full analysis more 

 time than has yet been devoted to them. The three; months spout in the vicinity of 

 Santa Fe during the past season by our party have, I trust, not been entirely without 



