Junius Henderson

“ Yesterday afternoon we visited a cavern a mile or two up the canyon which was cut by the wind in the hard cap zone which caps the cliffs. At the base of this zone there we found several narrow beds of still harder material distinctly separating the cap rock from the cliff tufa and at the same time forming a shelf for the large semi-circular cavern which the wind has eroded in the lower part of the cap rock itself thus
( (drawing in field book) )
The cavern is reached by several long ladders recently constructed in order to excavate it. ”

“ The reason this does not occur in the Rito de los Frijoles Rito de los Frijoles is that the hard stratum forming the cap of the cliff is traversed by numerous vertical or nearly vertical cleavage planes, so that it keeps falling to the talus as rapidly as erosion of the main face of the cliff progresses. It is probable, also, that the SW, facing NE, and hence suffering less from heat and consequence evaporation, is somewhat better protected by vegetation, which would serve to hold the debris on the slope and thus aid in preventing the formation of a cliff. ”

“ In the valley on N side of creek is a pueblo now being excavated. 60 rooms have been uncovered on the ground floor in about 1/4 of the ruin. Probably there were 250 on the ground floor and about 150 above. Unlike most community houses of this district, it is nearly circular. The only exit yet found is on the east side.
The slope of the stream bed and of the rim of the canyon and of the tops of the mesa are all about the same as that of the chief wall of tufa on the north side, so that the stream bed, base of the wall, top of wall and rim are approximately parallel. ”

“ The entire formation of the chain [W of the Rio Grande Rio Grande] as far as it faces the Rio Grande Rio Grande, is volcanic, the walls of the gorges consisting generally of a friable white or yellowish tufa containing nodules of a black, translucent obsidian. The rock is so soft that in many places it can be scooped out or detached with the most primitive tools, or even with the fingers alone. ”

“ Then above the upper are heavy rapids. As the stream has doubtless been completely dry at times as far as surface water is concerned, and fish could not get up from the river, it is probable that there have been no fish here for centuries and perhaps never. (see note further on) . The sandstone have evidently been deposited by rather evenly flowing but strong currents, not al all tumultuous. The stratification is very even but very pronounced, showing no crossbedding, no cutting and filling, containing coarse gravel in many places and as above mentioned large angular blocks of basalt. ”

“ At Las Flores Las Flores Estancia, we started up the track, then crossed on a wagon road to the beach, then north up beach. Shells not abundant except Donax laevigata Donax laevigata, which thickly strewed the beach. Good walking for first half, after which the beach became steep and of soft sand, the hard beaten sand being covered by the surf, but with a good cow trail for the last two miles at the foot of the cliff. Cliff nearly vertical, with hard sandstone unconformably overlaid by coarse conglomerate about 100 feet thick, with some deep gulches dissecting it. ”

“ Robbins and I started out at 9 a.m., going up to Flag Creek Flag Creek, Colorado road to cross river to south side. The valley here occupies the upper Mancos formation, with Mesa Verde forming strong bluffs on North side. Dip approximately 15° NW. The Mesa Verde, as usual, is composed mainly of sandstones, with some shales. Several coal veins crop out along the bluffs, at least one of which is being worked. Where we reached the south side of the river a low bluff is composed of shaley sandstone like portions of the Pierre north of Boulder Boulder, Colorado. ”

“ However, there are several, broad ill defined, rather irregular hard zones in the tufa, one of which is at the top of the nearly vertical cliff. These hard zones of course exist on both sided of the canyon. They are much reddened by iron oxides. The material below it is very yielding. If the storms beat more fiercely against the NE wall, they would weather the material on that side very rapidly without much affection the hard zone, and would have much less influence upon the SW wall. Consequently the tendency would be to produce a bluff on the NE side and none on the SW side. ”

“ After breakfast, Markman went at his traps again, Dodds looked after camp affairs, while Harry and I took the big dip net and began dipping for mollusks mollusk, but the creek was high and quite roilly, so we could see nothing, hence worked at a disadvantage. We collected quite a number of Ancylus Ancylus, however, clinging to the rocks which we fished out with the net, and a few insect larva. The creek was rising so rapidly that we concluded to pack up and get off the island before the water got too deep for fording. This warm weather means water too high for stream collecting. ”

“ Drove through another ranch where there were water holes then on to the NE for Eastman’s Lake Eastman’s Lake. Roads generally much better than from Boulder Boulder, Colorado to Greeley Greeley, Colorado. Occasional pass over hills covered with water worn debris from the mountains just like the mesa caps near Boulder Boulder, Colorado, but not flat. Intermittent channels are also strewn with boulders and gravel and the soil generally sandy but hard. ”

“ The last jump of the falls is sheer over a vertical 60 ft. wall formed by a joint plane in the granite just before leaving the granite. The granite lies on both sides of the lateral valley which cuts in from the north at the lower fall. In other words the lateral drainage cuts back into the granite as it does in the region of Boulder Boulder, Colorado, instead of cutting along the contact or into the sedimentaries. This is likely due to the fact that the sedimentaries were laid on a surface of weathered granite. ”

“ A few miles before reaching Palmer Lake Palmer Lake, Colorado trees disappear to some extent from the valleys. The rocks to NW of R.R. are abrupt and carved into turrets and monuments. Do not recognize the formation. Palmer Lake Palmer Lake, Colorado is right up against the foothills, but does not seem an attractive place. The foothills appear to be Dakota sandstone. Only birds recognized to Colo. Springs Colorado Springs, Colorado were magpies Magpies, and a few redwing blackbirds Red-winged Blackbird and many Mourning Doves Zenaida macroura. ”

“ Burnham, who lives 3 miles out of town, called and told us of a fossil locality on east slope of Cedar Ridge Cedar Ridge, Colorado, about 4 miles east of town. After dinner Mr. Keyser hitched up his horse and took terry and me up there. The ridge is a dome fold Meeker Dome ( (Meeker Dome) ) , bringing the Dakota up and exposing it by the denudation of the overlying Mancos. In one place a gulch exposes Jurassic strata. To the east and west are Mancos shales. The basal Mancos on the east is composed of hard black shales, with a sandstone above containing numerous plant stems. ”

“ The igneous inclusions sink instantly, the light tufa very slowly, especially the very light pieces which look like an older tufa included in the new. In the cliffs no assortment whatever occurs. I do not believe it could have been deposited in water. Why have this canyon and the Rio Grande Canyon been cut through basalt in places instead of along the vertical contact? Are prevailing winds from the south. Judge Abbott says south winds passing over canyon produce an eddy, so that they blow toward his house from the north. This would suck out soft material on north side and affect cliff. ”

“ At Owl Canyon Owl Creek Canyon, Colorado (mouth of) found great numbers of Ostrea Ostrea and Inoceramus Inoceramus. The latter look very much like I. labiatus Inoceramus labiatus. They occur in calcareous bands about half way down the west slope of the upper sandstone member of the Dakota ridge. Beginning at top of ridge we find, not the usual hard, thick bedded sandstone, but a softer thin bedded sandstone, weathering rapidly, perhaps 20 feet thick with numerous fucoids ? ”

“ The whole wide valley is a beautiful example of glacial topography. The glacier headed on E side of James Peak James Peak, Colorado. Teller Lake Teller Lake is morainal, and is very near the mouth of the gulch. At present South Boulder South Boulder Creek, Colorado is the main stream and Mammoth is a tributary. Came down E valley on way back, and followed railroad through cuts which expose gneiss ridges extending out diagonally into the South Boulder valley South Boulder Canyon, apparently the result of fluting by the glacier as in the upper North Boulder canyon North Boulder Canyon. ”

“ The formation much resembles the Hygiene sandstone at Left Hand Creek Left Hand Creek, Colorado, but is full of great concretions of sandstone with an outer coating of iron oxide. It dips to the eastward at a very low angle. This in weathering makes a sloping escarpment to the west, with a rise, followed by a gentle slope to the east. Facing the westward escarpment is the upper Niobrara escarpment skirting the foothills as at Little Thompson Creek Little Thompson Creek, Colorado. The concretions are filled with fossils, Inoceramus oblongus predominately, Callista sp. ”

“ The upper part of the bluffs, however, are irregularly concretionary and in many places the underlying marls have assumed a whitish color and are very soft, the irregularity of the white bands strongly resembling unconformity, the dividing lines being very abrupt. The debris slope is a gentle curve to the south, as at Chalk Bluffs Chalk Bluffs, Colorado, winding ravines 10 to 25 ft. in depth, with steep walls extending out for a mile or so until they shallow to nothingness, leaving the prairie beyond free from ravines. ”

“ Robbins left on horseback at noon for Newcastle Newcastle, Colorado, 40 miles distant, to catch the train and return to Boulder Boulder, Colorado on account of his mother's illness, having failed in his effort to get telephonic or telegraphic communication. Terry and Robbins caught 3 trout this forenoon and Felger put up bird skins. Felger is now (4:45) out hunting. At 6 p.m. he came in with a lot of doves Zenaida macroura and I cooked a trout supper. It has been a beautiful day. Threatening rain for a while in afternoon but not raining here. Mosquitoes are bad here. ”

“ Roads quite muddy. Reach gulch where home supply and Handy ditches leave foothills at 8:15. At top of Lykins red beds are of massive pink sandstone, overlaid by slightly pinkish but nearly gray massive transition (in color) beds, all weathering roundly, above which is a gray slabby sandstone weathering in low angular blocks and benches, some layers pitted by dissolution of greenish clay or lime nodules 1⁄4 to 1⁄2 inch in diameter. Yellowish sandstone and one foot angular limestone found above this at Box Elder Boxelder Creek, Colorado is missing here. ”

“ Neither rain, nor wind, nor both, would produce such cliffs in a perfectly homogeneous material such as the tufa seems to be at first glance. Certainly the upper part of the cliff has been longer exposed to the attacks of storms and other atmospheric agencies than the lower part, for the attack began on the upper part as soon as the downward cutting of the stream began to form an incipient canyon, and has continued ever since, while the lateral erosion of the lower part could not have begun until the stream reached the lower level. ”

“ The dip of cleavage planes is very steep, dipping west, with a strike a little W of N, approximately the same as the sedimentaries to the west, and so pronounced as to make the mountain in places look as if composed of stratified rocks. The western formations are a normal monocline. The anticline east of Masonville Masonville, Colorado seems to have overturned and developed into a thrust fault which has carried it up over the Dakota, and all the formations above the Lyons have been planed off. ”

“ I have concluded that Robbins' "deer signs" are all mad by sheep. I have seen no unmistakable deer tracks.
At the divide I saw three turkey vultures. Turning N, I soon found a flock of 20 or 30 turkeys in dense spruce timber. Tried them with the little gun, but without success, so turned back reaching camp at 12:45. As there was no one in camp I cooked my dinner and ate it. Saw gray headed juncos and crossbills up on top of the mountain. Obsidian flakes are found, scattered all over the mountain sides, as at Rito de los Frijoles. Santiago returned at 2:30 with 7 dusky grouse. ”