152 GEOLOGICAL SUEVEY OF THE TERRITORIES. 



riglit angles to the strike of the range or eastward, and present an east 

 front with nearly horizontal strata. 



All the ridges along the flanks of Wet Mountain have a general strike 

 of northwest and southeast, and run out in the plain. Wet Mountain 

 also flexes around slightly so as to end nearly or quite in a south trend, 

 while the ridges appear again on the southwest and west side, running 

 up into Huerfano Park. Here we see on the west side of the Wet Mount- 

 ain range, the red beds and cretaceous formations, corresponding to 

 those on the east side. The park is largely occupied with the calcareous 

 shales of No. 3. 



Just before reaching Badito, in the Sangre de Christo Pass, there is a 

 long ridge, extending down westward from the Wet Mountains, which is 

 composed mostly of the red and white sandstones of the triassic, inclin- 

 ing twenty-five to thirty degrees. At Badito we find mostly a reddish- 

 gray quartzose sandstone like No. 1, and it forms the foot-hills of the 

 mountains. As usual the dip of the bed is in various directions and at 

 different angles. The. Huerfano Creek is a fine stream with a moderately 

 wide valley which is all cultivated by Mexicans. Huerfano Park is 

 about fifteen miles long and from three to five wide, and is already filled 

 with settlers. It is surrounded on all sides by mountains composed of 

 igneous and metamorphic rocks. Black Butte, the principal peak of Wet 

 Mountain range, appears perfectly round or mammiform and is basaltic. 

 Scattered over the area of the park are several outbursts of basalt. The 

 cretaceous beds dip south in some i:)laces ten to twenty-five degrees; in 

 others they are nearly horizontal. As we ascend the pass by the road 

 we can see three considerable ranges called the Yeta Mountains — one 

 range on the north side and two on the south side — all igneous rocks. 

 They all have sharp sierra-like summits. 



These dikes have so heated the sedimentary rocks in their vicinity 

 that we have here every variety and grade between unchanged and 

 changed rocks. The summits and sides of these mountains are covered 

 with a continuous mass of debris of broken rocks, and this mass has the 

 appearance of being just ready to fall down, like an immense land-slide. 

 On the sides of the mountains near the pass are belts of quartzose sand- 

 stone, some of it a pudding-stone — really forming a iDortion of those seen 

 on the west side, for I do not think we come to the axis here until we 

 find the granitic belt, some eight or ten miles west of the immediate 

 summit of the ijass. We therefore have the cretaceous rocks, limestones, 

 and sandstones, and then the reddish sandstones at the summit, and 

 then farther west the full series of carboniferous limestones. From the 

 divide between the Greenhorn and Cuchara creeks, looking southward, 

 is one of the most extended and beautiful views on our route. The long 

 level benches extend down from the mountains, apparently breaking off 

 from point to point, and appearmg high at the place broken. These 

 benches are i)laued off so as to look like long tables, and, with the valleys 

 between them, seem to me to show clearly the direction of the eroding 

 force. All these benches are underlaid by the soft sandy marls of Nos. 

 2 and 3, cretaceous. 



Huerfano Butte rises up in the midst of the plain in the valley of 

 Huerfano Creek. The rocks are basaltic, some portions a true syenite. 

 It is evident that it is a portion of a dike which has extended north- 

 east from the mountains. Much of the rock is massive igneous granite. 

 Pragmentsof cretaceous clays, changed by heat, are scattered around the 

 butte. It seems to me that this is a dike, thrust up before the super- 

 incumbent beds were swept away, and that the igneous material never 

 reached the surface in a melted state. The butte is about two hundred 



