COLORADO AND NEW MEXICO ROCKIES 





Wet Mtns. 



^■ ^Wet Mtn Valley 





> j '''iSTTtiri 



I i It 



5Miles 



Fig. 25.9. Generalized and diagrammatic sections across the north central part of the Sangre 

 de Cristo Mountains. See section C, Fig. 25.1. 



Section A constructed chiefly from a traverse across the range near Crestone. Symbols are 

 generalized: solid black pattern (base) represents lower Paleozoic sandstones and limestones; 

 overlying crinkled line pattern, Lower Pennsylvanian beds involved in zones of shearing and 

 plastic deformation; lighter line and conglomerate pattern, higher Pennsylvanian and Permian 

 formations; the filling of the San Luis Valley depression is Late Tertiary and Recent alluvium, 

 and older lavas and gravels; intrusive bodies are entirely hypothetical but are at positions 

 corresponding to similar bodies exposed in other parts of the range. 



Section B is a diagrammatic representation of the same section, based upon the hypothesis of 

 an earlier phase of lower-angle overthrusts, which are presumed to be responsible for the greater 

 part of the shallower tangential deformation in the marginal belt. From Fig. 1, Burbank and 

 Goddard, 1937. 



of lava. This is a post-Laramide tectonic event, and it is believed to have 

 started not sooner than late Oligocene. 



The structure of the Sangre de Cristo Rrange southward in New 

 Mexico is less complicated, and the mountain front resembles that of the 

 Colorado Front Range (Smith and Ray, 1941). 



NEW MEXICO ROCKIES 



Geography 



The Rio Grande flows southward through central New Mexico from 

 Colorado to El Paso, Texas, a distance of 450 miles. It occupies a series 



PERIOD 



PLIOCENE OR 



PLEISTOCENE/ 



EOCENE 



UPPER 

 CRETACEOUS 



LOWER CRET. 



UP. JURASSIC 



FORMATION 



Terrace gravels 



Huerfano fm. 



Cucharafm. 



Poison Canyon fm. 



Possibly including 

 beds equivalent 

 to f/oton form- 

 ation. 



Vermejo fm. 



Trinidad ss. 



Pierre shaJe 



Apishapash 



Timpas Is. 



Carlile sh. 



Greenhorn Is. 

 Grejieros sh. 



So 



°5a 



.Dakota. _ss. 



Purgatoire fm. 



Morrison fm. 



----^--i-H I60-2Z5 



*E3tofrPS3F-£3- 



THICKNESS 

 IN FEET 



E30O-35O0 



300-500 



2000-3500 



0-4-50 



^^3^ 1800-2000 



==^S=S1 450-500 



I80-2OO 



no -180 



30- 4-0 



350-4-00 



GENERAL CHARACTER 



Moris, cloys, soft sandstones 

 ond shales, predominantly 

 red, but in port gray, yellow 

 green and purple. 



White on 3 pink so-idstone wrth 

 thin layers of snole; surface 

 cavernous. 



Arkosic sandstone ond flna 

 conglomerate, with thin beds 

 ofyeilow cloy; loner beds 

 weother poieye/iow. 



P.rl zho^. I J'i arty friotle sor^rsto^ 



o"d cool in alternate layers. 



Massive soodstom.sholy in lower po t 



Yellowish pray to dork grey 

 shales, witn zone of impure 

 limestone concretions. 



Bluish gray shales ot base, 

 grading upward through papery 

 shales to sandy shc/es 



Gfwbh *h;te b cc ■ a^'c~>TZvs j r 



Dark gray shole, coppec 'by y&.'cuish ss. 



Thin-beetled dove colored limestone. 



Gwtobhdt sh ¥t/UiumuttHjus v ~~ '-~<g 



Dense, finegrained sandstone. 

 Coarse, yellowish gray ss., overtoin 



by th.>n bed of gray shale . 



w< te • 



QrrJV She 

 pii and < 



. e scrdste~* f p ii ond yneen Stales 

 org' hard fine a Tzineo' li —cstone . 



Fig. 25.10. Mesozoic and Tertiary formations of Huerfano Park and vicinity, Colorado. From 

 Plate 3, Burbank and Goddard, 1937. 



