. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 170 BULLETIN : MUSEUM OF COMPARATIVE T ^.ii '•"•"•"••"•luiiii/a^'^z '-. '' For the greater part of the rauge front, the fans that spread forward from the ravines are not faulted, but near the junction of the southern and middle blocks, subrecent and recent faulting is conspicuous. The most interesting locality is near Hollis's ranch, Figure 18. Here several strong bluffs rise rather boldly from the plain, forming ter- minal escarpments to spurs whose interstream surface, GOO
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 170 BULLETIN : MUSEUM OF COMPARATIVE T ^.ii '•"•"•"••"•luiiii/a^'^z '-. '' For the greater part of the rauge front, the fans that spread forward from the ravines are not faulted, but near the junction of the southern and middle blocks, subrecent and recent faulting is conspicuous. The most interesting locality is near Hollis's ranch, Figure 18. Here several strong bluffs rise rather boldly from the plain, forming ter- minal escarpments to spurs whose interstream surface, GOO or 800 feet over the mountain base, seems to have been well graded and reduced to small relief before it was cut by the streams that are now eroding sharp ravines in it; but the same streams run forward on aggraded gravel fans east of the mountain base line. The bluffs between the streams occasionally show outcropping ledges, but most of the bluff face is an even slope of slide-rock at an angle near 35°. Just north of Hollis's ranch, the bluff must be nearly 1,000 feet high, but it rapidly diminishes in strength north and south ; and a mile and a half or two miles from the highest part of the bluff, the moun- tain base is of the usual gentle expression. The largest stream that cuts the bluff has a sharp-cut gorge next north of Hollis's ranch, whose irri- gated fields lie on the fan that the stream has built. Very recent fault- ing is indicated by fragments of an older fan, now standing about 150 or 200 feet above the present fan on either side of the canyon mouth. Next north and south there are two " hanging valleys," 500 or GOO feet over the plain, the like of which was not noted elsewhere along the Stein mountain front. Some of these local features might be explained, independent of fault- ing, by the occurrence of a mass of unusually resistant rock at this part of the mountain base; but in that case it might be expected that a greater number of outcro
Size: 1532px × 1630px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorha, bookcentury1800, bookdecade1860, booksubjectzoology
