DUTTOX.l 



BASIN OF THE VIRGEN. 81 



Virgen. Their channels are surely very wonderful freaks of nature. The 

 Parunuweap, after collecting its several filaments on the slopes of the 

 Cretaceous terrace, at length begins to burrow into the Jurassic, cutting 

 a very deep and remarkably narrow gap in the white sandstone, and 

 then into and through the Trias. For many miles it Hows in a mere 

 cleft barely fifty feet wide at the bottom and sometimes narrower, and 

 attaining a depth of more than 2,500 feet. In scouring down its channel 

 into the sandstones the stream did not cut always vertically, but swayed 

 from side to side, so that now great bulges of the wall overhang the bot- 

 tom of the abyss, and in some places shut out the shy overhead. The 

 M ukuntuweap, or Little Zion fork, is even more remarkable. For a con- 

 riderable distance this stream also runs in a profound and exceptionally 

 narrow chasm, but it at length widens out, and just where it joins the 

 Parfiimweap is a scene which must ultimately become, when the knowl- 

 edge of it is spread, one of the most admired in the world. Of this 

 hereafter. Below the junction of the forks the Virgen flows westward, 

 and passes out of the terraces and out of the Plateau Province. At 

 length it joins the Colorado. 



East of the drainage area of the Virgen is that of Kanab Creek. 

 It heads in the broad valley of Upper Kanab, which occupies an in- 

 dentation of the southern margin of the High Plateaus between the 

 Bfarkagunt and Paunsagunt. The bulk of the drainage passes through 

 the upper canon of Kanab Creek, and at length emerges upon the 

 desert to the southward. Further on it sinks another chasm in the Car- 

 boniferous, which becomes a mighty side gorge of the Colorado, and 

 unites with the Grand Canon in the middle of the Kanab division. 



Still eastward is the great amphitheater which gives rise to the branches 

 of the Paria. This stream Hows southeastward and ultimately enters 

 the Colorado at the head of the Marble Canon. 



In these three subordinate drainage basins of the terraces it is well to 

 notice some features of importance, common more or less to all, but 

 most distinctly seen in Kanab Creek. They all run contrary to the dip 

 of the strata. The summits of the terraces dip to the northward, while 

 the streams run southward. They thus form each a chain of canons. 

 Thus, Kanab Creek with its upper tributaries flowing in open valleys 

 soon begins to cut into the Jurassic, and its gorge, ever deepening, at 

 length becomes nearly a thousand feet in depth. Suddenly the cafion 

 walls swing to right and left to form the mural front which terminates 

 the Jurassic terrace, and the river, now at the summit of the Trias, is 

 once more in open country; but only for a short distance, for it soon be- 

 gins to cut into the Trias, forming a great canon as before. The same 

 process is repeated and the river flows out of its Triassic chasm into the 

 open again, while its walls swing in either direction to form the terminal 

 escarpment of the Triassic terrace. 



The three streams just mentioned are not the only drainage channels 

 in the terraces, though they are the principal ones, and sooner or later 



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